000 FXUS66 KSEW 281735 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 935 AM PST Mon Nov 28 2022 .UPDATE...While some showers remain in the area this morning, conditions are drying out. The winter storm warning for the Cascades and the Winter Weather Advisory for the North Olympic Peninsula will expire at 10AM. Looking ahead there remains a lot of uncertainty with the forecast for Tuesday-Wednesday. Lowland snow is expected, how much is the question. With southerly low level winds temperatures are expected to be warm enough to keep most of precipitation in the form of rain; particularly for south of Puget Sound and along the coast. For all other areas, precipitation type is going to be very dependent on precipitation rates as well as how much cold air moves into the area today and early tomorrow. Conditions are going to vary throughout the region over the course of this week. Make sure to check the latest forecast before heading out. The previous forecast discussion with updated aviation and marine section is below. && .PREV DISCUSSION... /issued 455 AM PST Mon Nov 28 2022/ .SYNOPSIS...Active weather will continue across the region through much of the week ahead. Expect continued showers to maintain mountain snow and lowland rain or rain and snow this morning. Dry but cooler conditions develop late Monday through early Tuesday, but the next weather system quickly approaches. Cool and unsettled weather continues late in the week with additional chances for lowland snow at times as additional disturbances cross the region. && .SHORT TERM /TODAY THROUGH WEDNESDAY/...Plenty of showers remaining in the Cascades and across the northern portions of Puget Sound this morning. The Winter Storm Warning for the Cascades (from Snohomish through Lewis counties) continues with a few more inches of snow expected today. Meanwhile, some showers across Whidbey Island and east through the I-5 corridor from Whatcom through Snohomish counties may occasionally contain some light snow or a rain/snow mix over the lowlands, but given the relatively weak precipitation rates and temperatures holding a few degrees above model guidance, have elected to cancel the advisory for Whatcom/Skagit/Snohomish counties. Confidence remains lower along the eastern Strait of Juan de Fuca, especially through the Sequim to Port Angeles corridor. While the expected Fraser outflow has been slow to materialize, this is expected to still develop with the potential for some upslope enhancement across the northern Olympic Peninsula. Otherwise, we`ll see showers diminish from north to south through the day, and a dry afternoon for most. The next weather system will then quickly approach the area on Tuesday, with the leading precipitation expected to reach the Olympic Peninsula by early afternoon. With cooler air in place, especially if the current timing holds true, expect to see some light snow to fall at onset with the moisture running ahead of the approaching warm front. Southerly low-level winds should bring a slight bump in snow levels and preclude much in the way of snow accumulations south of around Tacoma. Meanwhile, confidence is lower for around Seattle, where the timing of the warm southerly flow arriving and the moisture leads to a somewhat tricky forecast where a few degrees in the temperature profile is all the difference between a few inches of accumulating snow and a cold 35 degree rain. The most likely scenario for accumulating lowland snow during this time would be during periods of heavier precipitation, where enough cold air is dragged down to the surface. Snow levels are then expected to drop back down below 1000 feet by Wednesday afternoon. With colder air filtering in Wednesday the threat of accumulating lowland snow increases and will remain. One additional note with winds increasing ahead of the cold front late Tuesday night into early Wednesday. While no headlines have been issued yet, guidance continues to trend upward with respect to winds increasing. Gusts up to 55 mph are possible through the San Juans and Admiralty Inlet areas, while the windy spots in Whatcom and Skagit counties may see gusts to near 45 mph. Meanwhile, confidence is higher that another round of heavy snow will come to the Olympics and Cascades late Tuesday through Wednesday or perhaps even through Thursday. .LONG TERM /THURSDAY THROUGH SUNDAY/...Expect an unsettled weather pattern to remain for much of the second half of the week with below normal temperatures returning. With additional rounds of moisture rotating through, there will likely be additional showers that bring the potential for snow flurries down in the lowlands. This next one Wednesday night into Thursday looks to be merely light snow showers, but again plenty of details yet to be worked out so for now the key message is to remain aware of the possibility. The other main point here is that temperatures look to remain quite cold through the week ahead with lows in the 20s and highs only topping in the mid to 30s on Thursday across the interior. Below normal temperatures then likely to continue late in the week, and with snow levels remaining low, will need to closely monitor the potential for snow to again fall in the lowlands at some point. && .AVIATION...Upper troughing is moving across the Pacific Northwest this morning with Northwesterly flow. Any lingering MVFR decks will improve to VFR through the rest of the morning with clearing. Showers will taper off late morning for most areas. Increasing Fraser River outflow winds at KBLI today with mainly northerly winds. KSEA...Any chance for MVFR ceilings is decreasing through the rest of the morning. By noon, high confidence in VFR criteria as clouds scatter. Northerly winds for the remainder of the day before shifting towards the south later tonight into Tuesday morning. McMillian && .MARINE...The flow will transition offshore and strengthen through the day. Gusty Fraser Outflow winds today for the northern inland waters with a Gale Warning in place. Small Craft Advisory winds are in effect for all waters through this morning for the increasing north/east offshore winds. Offshore winds will taper off this evening and into tonight. A rather brief period of light winds is expected Tuesday morning. A strong weather system will move through Tuesday evening and Wednesday for increasing south/southeasterly winds across the area. Gales are likely for the coastal waters during this time period, as well as the northern inland waters, Puget Sound, Eastern Strait of Juan de Fuca, and Admiralty Inlet. In addition, there is a chance for Storm Force winds gusts across the Eastern Strait of Juan de Fuca Tuesday night into Wednesday morning. Winds will taper a bit Wednesday afternoon for additional Small Craft Advisory winds. Offshore winds increase Wednesday night and into Thursday. Seas of 10 to 13 ft will subside tonight into Tuesday morning to 7 to 9 feet. Seas will build Wednesday to 13 to 17 ft subsiding Thursday into Thursday night. JD && .HYDROLOGY...No river flooding is expected through the next seven days. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Wind Advisory until 10 PM PST this evening for San Juan County- Western Whatcom County. Winter Weather Advisory until 10 AM PST this morning for Admiralty Inlet Area-Eastern Strait of Juan de Fuca. Winter Storm Warning until 10 AM PST this morning for West Slopes North Central Cascades and Passes-West Slopes South Central Cascades and Passes. PZ...Small Craft Advisory until 4 PM PST this afternoon for Grays Harbor Bar. Small Craft Advisory until 10 AM PST this morning for West Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory until 10 PM PST this evening for Admiralty Inlet-Central U.S. Waters Strait Of Juan De Fuca-Coastal Waters From Cape Flattery To James Island 10 To 60 Nm- Coastal Waters From Cape Flattery To James Island Out 10 Nm- Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm-East Entrance U.S. Waters Strait Of Juan De Fuca-Puget Sound and Hood Canal. Gale Warning until 10 PM PST this evening for Northern Inland Waters Including The San Juan Islands. && $$

000 FXUS66 KPQR 281900 AAB AFDPQR Area Forecast Discussion...UPDATED National Weather Service Portland OR 1100 AM PST Mon Nov 28 2022 Included update section .UPDATE...Significant new snow accumulation threat has ended for today across the north Oregon and south Washington Cascades so had left the Warning expire. Probably could have done the same with the Lane County Cascades as only a few inches of additional snow are expected. However, decided to keep the product going given a fair amount of showers still visible on the radar which is somewhat impressive given that distance from the RTX and MAX radars. That implies some heavier snow rates. Then attention next turns to tonight and the Tuesday morning commute. Showers will certainly be dwindling tonight but not necessarily completely going away. Still have concerns about widespread temperatures hovering around freezing, especially for the lower elevations. Any liquid water still on the roads has a significant chance of freezing into black ice. Some of the very spotty shower activity as shown by the coarser models could produce some light snow. However, amounts are currently expected to be very light and the hi-res models show very few, if any, showers across the lower elevations. Am unlikely to issue any winter products covering Tuesday morning. That said, the next frontal system will arrive and spread stratiform moisture across the area Tuesday afternoon. Snow levels should rise during this time but may not completely clear above the Cascade passes by sunset. The bulk of the precipitation rates will occur Tuesday night and Wednesday as the cold front approaches the coast and drops south and inland across the area. Will be looking at issuing winter products today, certainly for the Cascades. /JBonk && .SYNOPSIS...Heavy snow accumulations will continue in the Cascades through this morning before diminishing. A brief break overnight into early Tuesday morning, before additional storm systems dropping down from the north bring rounds of rain and high elevation snow throughout the week. There remains a chance for light snow across the interior lowlands Thursday and Friday. && .DISCUSSION...TODAY THROUGH WEDNESDAY NIGHT...Numerous showers visible on satellite and radar continue to drop into southwestern WA and northwestern OR on the backside of an upper trough digging into the intermountain west. A jet streak oriented along the British Columbia coastline, putting the forecast area in the left front quadrant, will continue to enhance showers into the area while dropping snow levels. Good orographics continue to squeeze out all moisture it can from the showers, resulting in the heavy snow into the Cascade mountains and foothills. Already on radar and satellite, a decrease in shower activity up near Puget Sound, falling behind the area of jet induced lift, will start spreading south to start diminishing the precipitation. Therefore, the Winter Storm Warning remains in place through 10 AM for the WA and north OR Cascades as well as an Advisory for the foothills of the OR Cascades, and through 4 PM for Lane County Cascades. As colder air aloft advects in, the air mass will destabilize more, keeping a slight chance of thunderstorms over the relatively warmer ocean, moving inland late this morning and into early afternoon. As the shortwave trough moves further into the intermountain west, an upper ridge will briefly move overhead tonight. Light west to northwesterly flow from 850mb up may result in some flurries into the Cascades, but drier air will bring breaks in the clouds and temperatures will plummet. Lows will be below freezing almost everywhere, except the coast. There continues to be small hints of the possibility of light snow to fall late tonight into early Tuesday morning, with the CMC model showing the greatest chance. Still having a hard time picking out why this would happen, as there will be slight offshore flow in the low levels, and we`ll be between systems. There are a few weak impulses in the northwest flow aloft, but felt like this is such a small chance, that it was removed from the forecast. The next system will drop along the British Columbia coastline Tuesday. Precipitation from this system should arrive along the coast around noon before spreading further in. The warm sector will boost snow levels up through the day, but they`ll be starting below 1000 feet Tuesday morning, and any initial precipitation may fall as snow or rain/snow mix, before the warmer air is able to spread east and scour out all the cold air. Winds will begin increasing out of the south on Tuesday as well ahead of the cold front. Winds will continue increasing Tuesday evening and overnight ahead and along the cold front. Gusts of 35 to 55 mph will be found along the coasts, while gusts of 25 to 35 will spread inland. The bulk of the moisture will also push in from Tuesday night into Wednesday evening. Snow levels are expected to rise to about 3500 by Wednesday morning, then slowly drop again to near 2000 feet by Wednesday night. As the upper trough drops further south, it slows down near Vancouver Island during Wednesday as the low becomes nearly vertically stacked. This will continue to pump in good moisture, with PW values currently forecasted around 180 percent of normal. The mountains will likely need another highlight to deal with this next system, but will let the current highlights end today before issuing more. .LONG TERM...THURSDAY THROUGH SUNDAY...As the upper trough drops over the forecast area Wednesday into Thursday morning, there is good agreement in models that unsettled weather will continue as yet another upper low drops in from the north. NBM has snow levels fluctuating in the 700-1500 feet range Thursday, which may result in some isolated areas of lowering down to the floor. THerefore, from the period of Wednesday night through Friday, there will be potential for lowland snow. The next system will then spread precipitation Friday into Saturday. Confidence is high that the long term will be wet but whether the cold air will set up and stay in place long enough to produce the perfect conditions for low elevation snow is too early to tell. /Kriederman && .AVIATION...18Z TAFs: Northwest flow aloft continues while a cold and unstable air mass remains over the region today. Showers will persist into this evening, favoring the higher terrain while decreasing in coverage from north to south. As a result, will likely see a mix of VFR and MVFR conditions. Current trends indicate VFR will be predominant with brief periods of MVFR associated with heavier showers. The northwest 850 mb flow will maintain frequent mountain obscurement through the 18Z forecast period. MVFR cigs should become much more widespread towards 15-18Z Tuesday as cloud cover increases ahead of a frontal system set to impact the region Tuesday afternoon through Wednesday night. For detailed Pac NW aviation weather information, go online to: http://weather.gov/zse KPDX AND APPROACHES...Expect light and variable winds to continue today and tonight with predominantly VFR conditions. That said, brief periods of MVFR cigs are possible with passing rain showers later this afternoon and evening. The best chance for showers appears to be from 22Z Monday through 03Z Tuesday. The probability of MVFR cigs increases to over 50% after 15Z Tuesday. -TK/DH && .MARINE...An area of weak low pressure near the Washington coast will maintain breezy northwest winds across the waters today with gusts to around 20-25 kt. Seas are currently hovering around 11 to 12 ft at 14 seconds. Expect the increasing northwest swell to build seas to around 13 to 14 ft this afternoon. Will maintain the hazardous seas warning today across the outer waters, particularly beyond 30 NM. A longer period swell pushes in later this afternoon while seas subside overnight to around 10 ft by Tuesday morning. As weak high pressure passes overhead tonight winds ease to 5-10 kt. A developing low pressure in the Gulf of Alaska will strengthen as it moves southeast toward Vancouver Island on Tuesday. A strong cold front associated with this low will push into the region likely resulting in the strongest winds over the waters so far this Fall/Winter season. Solid Gale Force wind gusts of 35-45 kt appear likely across the waters Tuesday night into Wednesday morning. Chances have increased to around 60-80% that Storm Force wind gusts of 50 kt materialize at Buoy 29 and Buoy 50 mid week. Given a coastal jet will likely form ahead of the front, the probability of storm force wind gusts with 10 NM of the coast is even higher. Due to these strong southerly winds, seas will respond and climb into at least the mid to upper teens Wednesday and likely remain in the teens through Thursday. Another storm system appears likely to bring another round of strong southerly winds and increasing seas around next Friday or Saturday. The new moon today will produce stronger tidal currents than normal during the evening ebb cycle. Those moving in and out of harbors and crossing coastal bars should use caution and be aware of any bar restrictions in place. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Winter Storm Warning until 4 PM PST this afternoon for Cascades in Lane County. WA...None. PZ...Small Craft Advisory until 10 PM PST this evening for Columbia River Bar. Small Craft Advisory until midnight PST tonight for coastal waters from Cape Shoalwater WA to Florence OR out 10 nm. Hazardous Seas Warning until 2 PM PST this afternoon for coastal waters from Cape Shoalwater WA to Florence OR from 10 to 60 nm. Small Craft Advisory from 2 PM this afternoon to noon PST Tuesday for coastal waters from Cape Shoalwater WA to Florence OR from 10 to 60 nm. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland

000 FXUS66 KMFR 281754 AFDMFR Area Forecast Discussion National Weather Service Medford OR 953 AM PST Mon Nov 28 2022 Updated AVIATION Section .DISCUSSION...Satellite and radar imagery show numerous showers across southwest Oregon. Showers are a mix of rain and snow showers. Snow levels have been around 3000 feet, except lower (around 2500 feet) across Douglas County and Coos counties. Snow levels will gradually lower late today into this evening, down to around 2000 feet. However, showers are expected to diminish in coverage and intensity during the evening. So any snow down to lower elevations will be very light. Then, lingering showers are expected at the coast and into the Umpqua and S. OR Cascades tonight. Otherwise, expect continued gusty winds over the mountains and east of the Cascades through this afternoon with gusts of 20-35 mph except stronger in the areas near Summer Lake and over exposed ridgetops (gusts of 35-40 mph). Winds will lower this evening. Wednesday and Thursday a strong and moist storm arrives, bringing the potential for significant impacts with heavy snow and winds. Heavy snow is possible over the mountains, especially the Cascades and Western/Central Siskiyou County as well as in the Mount Shasta and Weed areas. Moderate to locally heavy snow is also possible east of the Cascades. Gusty winds are also expected, especially in the Shasta valley, over the mountains and east of the Cascades. Gusty winds combined with snow may result in additional hazards with blowing snow creating reduced visibilities. We will be evaluating this period for potential of Winter Storm Watch. Please check back for updates. && .AVIATION...28/18Z TAFs...Expect a mix of VFR and MVFR conditions to continue this afternoon with showers and widespread terrain obscurations. Gusty winds will continue along the terrain and east of the Cascades, including KLMT into this afternoon. Wind gusts near 30 kt are expected at Klamath Falls. The front will push east of the area this evening and most showers will end, though some may continue into the overnight near the Cascades and over to the coast. Expect some IFR to develop overnight into Tuesday morning for the valleys west of the Cascades with patchy fog elsewhere. -Spilde && .MARINE...Updated 800 AM PST Monday 28 November 2022...Steep to very steep and hazardous seas will persist today due to a mix of a shorter period (12-13 seconds) higher swell and a longer period (15- 17 seconds) lower swell. The shorter period swell will peak today at around 12 to 16 ft. Seas diminish some later today into Tuesday, but will remain steep. A period of relatively improved conditions is expected Tuesday, but this will be short-lived as active weather returns Wednesday and continues into the weekend. A cold upper level trough will move into the region late Tuesday, bringing a cold front onshore Wednesday. Strong southerly winds are anticipated with this front, and a period of gales with very steep and hazardous seas are possible late Tuesday night into Wednesday morning. This will be followed by a building northwest swell Wednesday night into Thursday. && .PREV DISCUSSION... /Issued 353 AM PST Mon Nov 28 2022/ SYNOPSIS...An active week of weather is expected. A Winter Weather Advisory is Douglas, Jackson, and Klamath County, through Monday morning, with the most intense snowfall expected during the morning commute hours Monday morning. Active weather continues in the middle of the week with another front arriving Wednesday and heavy upslope snowfall in Norcal and SW Oregon is expected. This snow event has the potential to lead to disruptions to traffic along I-5. DISCUSSION...The forecast is on track with the Winter Weather Advisory /PDXWSWMFR/ in effect through Monday afternoon for elevations above 2500 feet in the southern Oregon Cascades and foothills of the Cascades, with light snow overnight also for south central Oregon and the mountains of Siskiyou County. A brief break between systems is expected Tuesday. A stronger system will approach at mid-week, Wednesday into Thursday. Snowfall from this system may result in widespread travel disruptions and much has been said about this midweek system in previous forecast discussions. So please refer to those for more details. This discussion will focus on some noteworthy though less directly impactful parts of the forecast. First is the chance for new daily temperature records at the Mt. Shasta City and Brookings climate sites. Both records being challenged are the low high temperatures. Both are forecast to be within one degree of the record. At Brookings record temperatures are possible on Tuesday, Nov. 29, as well as Thursday and Friday, Dec. 1 & 2. For Mt. Shasta City the records are being challenged on Dec. 1 & 2 as well. Additionally on temperatures, is that for the past 30 days, the average max and min temperatures have been below normal by 2 to 10 degrees. This means that while the looming cold, there should have been some opportunity to acclimate to the winter temperatures (or add some warmer layers, like this forecaster has done). Second is the need for this week of active weather with respect to precipitation totals. For the past 30 days the departure from average for precipitation low, by two to six inches. For the water year, which started in October, only the Alturas, CA climate site is above normal...by 1%. All the other sites are below by 22-46%. That said, snow pack depth in the region is roughly near normal. There are some places in the higher mountains where the snowpack is a bit below normal, for example at Crater Lake the snowpack yesterday was measured at 10" and normal is 23". Looking regionally at what this means for snow- water- equivalent (SWE) there is enough snowpack that the SWE is 100+% of normal everywhere. With more snow on the way, this is a welcome, but still early sign, that we may remain on track for a good snow winter snowpack. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 4 PM PST this afternoon for ORZ025. Winter Weather Advisory until noon PST today for ORZ026. Winter Weather Advisory until 4 PM PST this afternoon for ORZ027- 028. Winter Weather Advisory until noon PST today for ORZ030. CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 10 AM PST Tuesday for PZZ350-356-370-376. Hazardous Seas Watch from late Tuesday night through Wednesday afternoon for PZZ350- 356-370-376. Hazardous Seas Warning until 10 PM PST this evening for PZZ350-356-370-376. && $$ CC/MAS

000 FXUS66 KEKA 281314 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 514 AM PST Mon Nov 28 2022 .SYNOPSIS...With the passage of a weak cold front overnight, slightly below average afternoon temperatures and chilly overnight temperatures are expected to continue through this week. Light rain and high elevation snow are expected throughout today with clearing into Tuesday. A significant winter storm is expected by mid to late week. && .DISCUSSION...Today, a weak and cold disturbance will move through the region bringing light rain and high elevation snow. Anywhere from 0.15 inches to 0.40 inches is expected along coastal areas north of Cape Mendocino with the greater amounts expected in Del Norte County. Light snow accumulations above about 3000 ft MSL. are expected in the mountains of Del Norte and the Trinity Alps. Very chilly temperatures are forecast for early morning Tuesday as cold and dry air settles over the region with high pressure dominating. Just how chilly it gets depends on cloud cover late tonight and into Tuesday morning. If there is little to no cloud cover, radiational cooling would prevail causing coastal areas to potentially see near freezing to freezing temperatures. As a result, a freeze watch is in effect for the Del Norte, northern Humboldt and northern Mendocino coasts. A freeze warning may be issued; however, the extent of cloud cover is still too uncertain at this time. A strong cold front associated with a low pressure system off the coast of Vancouver Island is expected to move through Northwest California on Wednesday. As a result, widespread chances for measurable rainfall and lower elevation snow are expected Wednesday night and into Thursday. This system has the potential to be a rather significant winter storm event for the region. Rainfall could reach over 1 inch to up to 3 inches, again with higher amounts in Humboldt and Del Norte counties. Also, windward facing slopes are expected to have higher amounts than other parts of the region. An intense band of precipitation moving in with the cold front could also cause concern for localized flooding. Flood prone areas and burn scars will be monitored. On Thursday, snow levels could be as low as 2000 ft MSL. Initially, the snow level could lower even more due to precipitation falling through the cold and dry air mass preceding the moist air influx. Further into Thursday, snow levels could remain low due to heavy precipitation and upslope flow. If the snow levels are this low, many highway passes in Trinity, Humboldt and Del Norte Counties would be impacted by heavy snow. The high elevation sections of Highway 101 in Mendocino county could even potentially see an inch or two of snow which would impact travel. Ensemble models indicate more possibilities of systems favorable for periods of rain and mountain snow into next week. In particular, another system could potentially affect the Pacific Northwest going into the weekend. Models are not in agreement on the placement of this next system, so this will need to be further monitored throughout the week. /JLW && .AVIATION...The frontal boundary is moving across the area this morning with a round of light rain. Showers have diminished behind this initial band along the coast, but are pushing inland and have lowered CIGS at KUKI. HIRES CAMs and IR satellite are showing a round of showers picking up again this morning. These showers will likely bring MVFR conditions, although it may be intermittent due to the showery nature. This afternoon, northwest winds will pick up to around 12 kt. Tonight skies are expected to clear out, however there is quite a bit of moisture around and this could lead to some fog. MKK && .MARINE...Northerly winds are increasing this morning behind a front that is moving across the waters. Tonight these winds will quickly diminish as another stronger system starts to approach the area. Winds will become southerly Tuesday night and rapidly increase on Wednesday with gale force gusts possible at least in the northern outer waters. By Thursday afternoon models are in fairly good agreement that winds will be northerly around 10 to 20 kt. Wednesday night and Thursday morning there are numerous different model solutions as the models struggle to resolve a strong surface front approaching the west coast. The NAM shows this low deepening to around 991 mb and bringing possible storm force gusts to the waters. This is the only solution, but it is possible with a strong a dynamic front such as this one. Models are in general agreement on another strong system bringing southerly gales to the waters Friday night and Saturday. Both of these systems will bring large steep waves. A swell around 7 feet at 12 seconds continues to dominate the waters this morning. There is a second swell just starting to move into the area. Currently this is just barely showing up in the spectrum plots, but should build to around 4 feet at 18 seconds this morning. These swells will generally persist through much of the week. Late in the week this swell will get reinforced by another swell and build to around 13 feet at 13 seconds. MKK && .HYDROLOGY...A multi-inch rainfall event is forecast to occur across Northwest California Wednesday evening through Thursday evening. Low-level moisture flux will be favorably oriented with west-southwest facing terrain such that locally heavy rainfall rates will be possible...particularly in the vicinity of the King Range. That could lead to some areas of urban and small stream flooding, as well as an increased risk for mountain rock and mud slides. In addition, there is a slight risk that rainfall rates may become sufficiently large for debris flow concerns across area burn scars. && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Freeze Watch from late tonight through Tuesday morning for CAZ101-103-109. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory from 9 AM this morning to 3 AM PST Tuesday for PZZ450. Small Craft Advisory until 3 PM PST Tuesday for PZZ455-475. Small Craft Advisory until 3 AM PST Tuesday for PZZ470. && $$ Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png

000 FXUS66 KMTR 281846 AFDMTR Area Forecast Discussion National Weather Service San Francisco Bay Area 1046 AM PST Mon Nov 28 2022 .SYNOPSIS...Cool and quiet through mid week with frost and freezing temperatures possible inland. An unsettled pattern develops thereafter with rain chances increasing for late week into the weekend. && .DISCUSSION...as of 09:37 AM PST Monday...A cool start to the day around the Bay Area and Central Coast, but not as cold as the last few mornings. Temperatures for the most part bottomed out in the upper 30s to lower 40s. Passing high clouds and a slight uptick in wind speeds this morning limited radiation cooling potential. For the rest of today - despite some sunshine it will feel colder today as a dry cold front sweeps through. A cold front currently over NorCal will pass through the Bay Area and Central Coast later today. The fropa still looks dry, but the latest hi-res runs of the HRRR and WRF show a pop-up showers possible over the coastal waters this afternoon. The bigger story with the fropa will be the change in airmass. Post-frontal conditions will usher in cold air. Therefore, temperatures this afternoon will top out in the upper 50s to lower 60s or about 5-10 degrees colder than Sunday. Putting this into climo context - near or a few degrees below normal for late November. The change in airmass will also set the stage for a colder night tonight. As noted below, interior portions of the forecast area have the best shots at seeing sub- freezing temperatures. Closer to the coast and bays gets a little more tricky with more mid 30s to near 40 degrees. Regardless, it will be a cold night. Colder temperatures are expected Tuesday night into Wednesday. Next weather impact will be a weak atmospheric river forecast to reach the Bay Area as early as Wednesday. This round of rain looks solid with a wetting rain all areas. Will fine tune the forecast after collaborating with neighboring offices and national centers this afternoon. && .PREV DISCUSSION...as of 02:00 AM PST Monday... Tonight: With cold advection and good radiational cooling look for temperatures to tumble with lows dropping into the upper 20s and 30s for most locations. The exception will be along the immediate coast and bays were lower 40s are expected. This will set the stage for areas of frost across many inland areas with a freeze likely (50-80 percent probabilities) for the North Bay Valleys, southern inland Monterey County, and for much of San Benito County. With colder temperatures arriving make sure to protect people, pets, plants, and pipes from the cold. Tuesday and Wednesday: Low amplitude ridging will prevail aloft as surface high pressure strengthens from the Great Basin through the northern High Plains. Daytime temperatures will remain cool with post-frontal conditions. Look for highs to reach the mid 50s to lower 60s, with the warmest readings within the inland valleys. Given light offshore winds and good radiational cooling chilly temperatures will prevail on Tuesday night into Wednesday morning. Overnight lows should drop into the upper 20s and 30s for most areas away from the immediate coast, with lower 40s expected along the coast and bays. There is a medium to high potential (50-80 percent) of experiencing freezing temperatures within the North Bay Valleys, southern inland Monterey County, and over much of San Benito County. It`s also worth noting that a low potential exists (20-30 percent) for temperatures to reach freezing within portions of the Santa Clara valley surrounding San Jose. Temperature trends will be monitored going forward with cold weather headlines possible depending upon how the forecast evolves. Regardless, this is a good reminder to both protect sensitive vegetation and to check on those without access to adequate heating during this period of colder weather. Thursday through Sunday: A sharpening upper trough will dig from coastal British Columbia into the northeast Pacific on Thursday into Friday. WPC Cluster Analysis ensemble members are in good agreement on this solution, with deterministic models and their ensembles also in phase. A southwest to northeast oriented frontal zone will accompany the upper system into NorCal with a focused push of warm/moist advection occurring ahead of the front. This should provide decent forcing for ascent when juxtaposed with large-scale lift provided via robust jet- level divergence and increasing differential cyclonic vorticity advection. Consistency in forecast model solutions over the past 24 hours lends increased confidence in seeing a notable rain event on Thursday into early Friday. National Blend of Model probabilities indicate that the North Bay and coastal ranges have the best potential for seeing higher rain amounts, with somewhat lower chances for the inland/rain shadowed valleys. Here are the probabilities of seeing rain totals of one half inch or greater on Thursday: 75% chance - North Bay Coastal Mountains. 60% chance - Santa Cruz Mountains. 45% chance - Santa Lucia Mountains/Big Sur. 70% chance - Santa Rosa. 50% chance - Napa. 50% chance - San Francisco. 30% chance - San Jose. 30% chance - Monterey. A secondary shortwave is forecast to reach the eastern Pacific and West Coast states over the weekend. This may provide additional rain chances during this time. However WPC Cluster Analysis ensemble members show some variability in the placement of this feature. So wet weather may continue into the weekend, but there is less certainty in the details until the upper pattern becomes clearer. Of greater confidence is the continuance of below average temperatures continuing. && .AVIATION...As of 10:40 AM Monday...For the 18Z TAFs. Weak frontal boundary is currently passing through the area, which will usher in breezy northwest winds this afternoon. Gusty conditions likely today with gusts up to 20-25 knots and maximum gusts at KSFO approaching 30 knots. Winds will diminish overnight, but will stay breezier aloft. Low-end LLWS possible for North Bay terminals, but not included in the TAF at this time but will continue to monitor. Valleys/low lying areas embedded within higher elevations such as over the Diablo Range and the Santa Lucias could see some radiation fog development overnight due to a cool down in temps in the post- frontal environment. However, terminals expected to remain VFR though the period. Vicinity of SFO...VFR. Northwest winds will continue to increase through the afternoon today. Strongest winds are projected between 21Z and 03Z with gusts approaching 30-33 knots. Winds will begin to diminish after 04z but will be breezy through the night with winds around 10 to 15 knots. Winds are also forecast to shift N/NNE early morning Tuesday before shifting back to onshore later in the afternoon. SFO Bridge Approach...Patchy low clouds have mixed out near the approach but could have a stray low cloud or two through the early afternoon. Monterey Bay...Patch of MVFR low clouds is quickly passing through MRY terminal. VFR expected for the period with lowered visbys staying confined to higher elevations overnight tonight. Northwest winds will increase throughout the day with FROPA. Gusts up to 20-25 knots possible this afternoon before diminishing this evening. && .CLIMATE.. Daily Record Low Temperatures Nov 29-30 11/29 Record Low Record Year Forecast Low Santa Rosa coop 25 2019 32 Kentfield 28 1931 40 Napa State Hospital 28 2015 34 Richmond 37 1906 40 Livermore coop 25 1975 35 SF downtown 40 1906 42 SFO 36 1954 44 Redwood City 28 1931 40 Half Moon Bay 34 2006 40 Oakland Museum 36 1975 42 San Jose Airport 22 1896 39 Gilroy 28 1976 35 Salinas Airport 27 2004 38 King City 23 2004 32 11/30 Record Low Record Year Forecast Low Santa Rosa coop 26 1933 30 Kentfield 26 1954 39 Napa State Hospital 27 1936 33 Richmond 36 1954 39 Livermore coop 25 1969 34 SF downtown 41 2004 41 SFO 31 1954 41 Redwood City 29 1954 38 Half Moon Bay 32 2004 38 Oakland Museum 38 2004 39 San Jose Airport 25 1896 37 Gilroy 28 1969 33 Salinas Airport 29 1933 35 King City 22 1954 29 && .MARINE...as of 10:01 AM PST Monday...Strong northwest winds will continue to increase featuring stronger wind gusts across the waters today. Gale force gusts are expected south of Point Sur coast through late this morning. A moderate period northwest swell of 10 to 12 seconds prevail and the seas become locally wind driven on monday. The next long period northwest swell arrives Monday evening. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tday...SCA...SF Bay SCA...Mry Bay SCA...Pt Arena to Pt Reyes 0-10 nm SCA...Pt Reyes to Pigeon Pt 0-10 nm SCA...Pigeon Pt to Pt Pinos 0-10 nm GLW...Pt Pinos to Pt Piedras Blancas 0-10 nm until 3 PM SCA...Pt Arena to Pigeon Pt 10-60 nm SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm && $$ PUBLIC FORECAST: MM/SPM AVIATION: McCorkle MARINE: McCorkle Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea

000 FXUS66 KOTX 281816 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1016 AM PST Mon Nov 28 2022 .SYNOPSIS... Bouts of light snow will fall at times through this evening. A major winter storm Tuesday night through Wednesday night will bring moderate to heavy snowfall to the region. Temperatures will remain below average through the week. && .UPDATE... Light snow will continue to fall over the Cascades but no significant snowfall is expected so the Winter Storm Warning has been cancelled. Light snow will continue to fall in the lower elevations today before clear skies move in for tonight. PoPs have been increased for the lower elevations as well as increased snow totals. Most lower elevations could see between 1 and 2 inches throughout the day. /KM && .DISCUSSION... ...Major Winter Storm Tuesday Night through Wednesday Night... Today through Tuesday: The trough will continue to dig today. A reinforcing wave combined with 500 mb temps of -38 to -40C will create unstable conditions with snow or graupel showers on and off today. It will be very hit and miss with some locations seeing a trace, and others close by getting 2 inches. Because of this will keep advisories going for portions of the Palouse, areas east of Lewiston, Camas Prairie, Blue Mountains and the central Panhandle Mountains. This is where the high res models are showing the higher qpf through the evening hours. However there is about a 40% chance of 0.01 of snow along a line from just east of Ritzville to Spokane to Sandpoint, with areas to the south of that line having higher probabilities. Once you go up to an inch the probabilities go down to about 10-15%. Not sure the NBM 4.1 is catching the unstable nature of this, which is incredibly difficult to do, but some locations may really have higher probabilities than what was stated. A northerly push will come down the Okanogan Valley into the Waterville Plateau and parts of the western Columbia Basin today. There is a 75-85% chance of gusts to 25 mph down the Okanogan Valley to Ephrata. And a 30% chance of Omak area seeing gusts to 40 mph. Winds will peak this afternoon and then decrease through the evening. The trough moves into the Rockies Tuesday with a ridge beginning to push in. Some partial clearing overnight combined with the northerly winds bringing some colder Canadian air to the region will bring some very cold temperatures Tuesday morning. Widespread single digit and teens is forecast. Even some below digit readings for the colder northern valley pockets such as Winthrop, Republic, Colville and Priest Lake. Clouds will increase through the day, which will keep our temperatures throughout the day about 12 degrees below average for the end of November...in the upper teens and 20s. Tuesday Night through Wednesday Night: A vertically stacked low will move offshore of Vancouver Island Tuesday night and then shift south off the WA coast Wednesday and Wednesday night. There are still differences in the ensemble forecasts in snow amounts and locations of heaviest snow. But the bottom line here is that is is gonna snow. Tuesday evening we will see good upslope flow into the Cascades which will continue through the night and into the morning hours. There is an 80% chance of Stevens Pass seeing a foot of snow. The mountains and higher terrain will see lots of snow. Down towards the valleys...for seeing 4 inches of snow the cities have the following probabilities: Omak 85%, Waterville 50%, Wenatchee 30% and Moses Lake 35%. Overnight the higher swath of precipitation will move eastward. There are differences btwn the GFS and EC ensemble on where to put this higher band of qpf. The EC wants to put it further north across Ferry, Stevens, Pend Oreille and Bonner counties, while the GFS ensemble has it in the southern portions of those counties and into Lincoln, Spokane and Kootenai counties. GFS ensemble has almost double what the EC ensemble is showing for qpf for Spokane, and therefore more than double the snowfall. The range between all 100 ensemble members for Spokane is between 2 inches and 15 inches. The current forecast for the Spokane/CDA area 8 to 10 inches with higher amounts the further north you go. Upwards of a foot of snow for Deer Park, Newport and Sandpoint. Looking at the NBM 4.1 probabilities greater than 8 inches, the area of highest values...65% or higher exist from Omak to Republic, Colville, Deer Park, Sandpoint. With 55% for CDA, 45% for Spokane and 60% for Lookout Pass. Given the snow will continue through the day continuously and into the evening hours, motorists: plan for long commutes, and if possible just stay home and shovel or snow blow your driveways multiple times to keep up. On top of the snow, winds will increase through the day across portions of the Columbia Basin and into Spokane and the Palouse. Have added some blowing snow into the forecast as any snow falling or has recently fallen could be light enough to blow around. Through the overnight hours the snow will primarily be focused in the ID Panhandle and parts of extreme eastern WA. Unfortunately, cannot rule out some snow north of Highway 2 to the Canadian border as well, but accumulations there should be light. Now is the time to start preparing for this storm. Make sure your vehicles are winterized and prepared for winter travel. Don`t go out Wednesday unless you need to. /Nisbet Thursday through Sunday: The Inland Northwest will remain in a progressive and unsettled pattern through the weekend and into early next week. Snow will continue into Thursday as the upper level trough moves onshore. Although the best chances for heavier snowfall Thursday look to be to the south of us, the NBM4.1 is giving far eastern Washington a 40-60% chance to see an additional 2 inches or greater of snow through 4am Friday. Additionally, it gives Lookout Pass a 60% chance to see over 8 inches of snow. Models suggest that snow showers will continue Friday as the next system slides down the Western US coast. There are still a decent amount of discrepancies among the ensembles on how far south this trough will dig, which impacts the snowfall forecast for the Inland Northwest. 52% of the ensembles suggest the trough to dig south of us, which would keep our forecast on the drier side through Saturday night. Because of this almost 50/50 split on snow or no snow, the forecast is quite uncertain after Friday. Regardless of the solution, it does look like we will remain cold through the weekend with highs in the upper 20s to low 30s and lows in the teens and 20s. /vmt && .AVIATION... 18Z TAFS: Large changes to the forecast for North Idaho and the eastern third of WA with snow showers, occasionally moderate to heavy, expected to impact Kellogg, Coeur D Alene, Spokane, Deer Park, and Sandpoint through 21z. Snow showers expected to linger well into the evening and overnight hours but at lighter intensities and could be slow to completely clear out of the Idaho lingering through 15z. IFR/LIFR conditions expected under the snow showers with lingering low stratus in between. Conditions improving on the backside of the system over Central WA around Omak, Wenatchee, and Moses Lake with a drier west to northwest flow. /sb && .PRELIMINARY POINT TEMPS/POPS... Spokane 25 8 23 17 33 26 / 40 20 0 50 100 80 Coeur d`Alene 25 10 23 17 32 27 / 60 50 0 40 100 90 Pullman 28 11 25 18 34 27 / 60 20 0 30 70 80 Lewiston 33 21 31 25 41 33 / 40 20 0 20 60 70 Colville 23 0 22 10 30 15 / 40 30 0 60 100 70 Sandpoint 24 11 20 16 28 23 / 50 50 0 40 100 90 Kellogg 24 10 23 18 33 30 / 70 70 0 30 100 90 Moses Lake 30 9 26 18 34 18 / 30 0 0 90 90 40 Wenatchee 30 13 22 19 29 21 / 40 0 0 100 100 40 Omak 22 6 19 15 28 17 / 10 0 20 90 100 50 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Winter Weather Advisory until 10 PM PST this evening for Central Panhandle Mountains-Idaho Palouse-Lewis and Southern Nez Perce Counties-Lewiston Area. WA...Winter Weather Advisory until 10 PM PST this evening for Lower Garfield and Asotin Counties-Northeast Blue Mountains- Washington Palouse. Winter Storm Warning until 10 AM PST this morning for Western Chelan County. && $$

000 FXUS66 KPDT 281753 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 953 AM PST Mon Nov 28 2022 .UPDATED AVIATION DISCUSSION...VFR conditions at KDLS/KYKM/KPSC and will remain VFR through the period. MVFR conditions at KPDT/KRDM/KALW and have been intermittent as the precipitation moves overhead and slowly out of the region. These TAF sites should return to VFR conditions this afternoon as the isolated showers move through. KBDN is LIFR currently with 1/4SM VIS due to snow, but should also return to VFR conditions this by this afternoon. Bennese/90 && .PREV DISCUSSION... /issued 859 AM PST Mon Nov 28 2022/ UPDATE...Upper trough digging southeast across the region will shift east of the area this evening. Already seeing some clearing skies east of the Cascades this morning. Snow is tapering off over the east slopes but will continue into the afternoon over the eastern mountains but decrease in intensity. Little additional accumulation is expected over the east slopes but 1-2 inches of snow is probable over the eastern mountains. Snow will end all areas tonight as a temporary ridge builds into the area. 78 PREV DISCUSSION... /issued 232 AM PST Mon Nov 28 2022/ SHORT TERM...Today through Wednesday night...The short term continues to be active, for at least through today. A winter storm continues to move across the region and forecast area this morning. Currently, the radar is showing precipitation continuing to move across the Cascades and also the eastern and northeast mountains. However, there seems to be less precipitation coverage than previously forecasted, especially over the lower elevations. The NBM v4.1 24 hour snowfall amount probabilities ending at 00Z this afternoon continues to show a high probability of storm total warning snow amounts over the Cascades (both OR and WA), and also over the Blue Mountains. Web cameras do show snow falling in these areas. The NBM v4.1 probabilities of 24 hour snowfall amounts of greater than 6 inches are in the 70 to 90 percent chance range over the Cascades and Blue Mountains. It is also showing probabilities of advisory amounts (24 hour snowfall amounts greater than 4 inches) in the same percentage range for the Ochoco-John Day Highlands. However, it is not showing as much of a probability of more than 4 inches, ending at 00Z today, over Wallowa County. It does show a high probability (mostly 70-90 percent) of greater than 2 inches over Wallowa County. Radar imagery is not showing much precipitation over Wallowa County, though the radar beam typically has a problem seeing low altitude echoes over Wallowa County due to beam blockage from the Blue Mountains. Cameras over Wallowa county do show snow is falling in some areas over Wallowa County. Also, there was a report earlier of 4.5 inches near Joseph, which is in the heart of Wallowa County. Still have high confidence that advisory amounts will still be met in both Wallowa County and the Ochoco-John Day Highlands by 00Z this afternoon. The Winter Storm Warnings for both the OR and WA Cascades end at 18Z this morning. It may need to be extended if the stream of snowfall, currently seen on radar, continues beyond 18Z, with the expectation of additional accumulations. This is especially true for the OR Cascades. The Warnings and Advisories for the eastern and northeast mountains all end at 00Z today, which still looks good. Storm total QPF amounts by the NBM and WPC, as well as the short range deterministic and ensemble models, show that the snow will decrease enough by 00Z to warrant the ending of the Warnings and Advisories there at 00Z this afternoon. Elsewhere across the forecast area, snow, or a mix of rain and snow is still expected through this morning, and possibly into the afternoon. However, accumulations will be very light, if any, and mostly less than an inch where there is any accumulation. Some areas, such as the Lower Columbia Basin will likely not have any snow accumulations at all, though there could be some light snow or a mix of rain and snow there this morning. Temperatures are not as cold as previously expected by this time. Most lower elevation areas are still showing temperatures mostly in the 30s to near 40. However, some locations, such as at KPSC is showing a current temperature of 28 degrees. This is likely due to some clearing there. High temperatures today for the lower elevations are expected to be in the 30s, with mostly 20s in the mountains. This current weather system will move to the southeast, with a large upper trough continuing to dig over the region with a northwest to north flow aloft. This will bring in colder air tonight and Tuesday, with high temperatures in the upper 20s to mid 30s in the lower elevations, and mostly lower to mid 20s in the mountains. Tuesday will be a dry day, except for possible lingering light snow flurries over the mountains. The next weather system is then forecast to bring snow back to the Cascades again by Tuesday evening, which will spread to the eastern and northeast mountains by early Wednesday morning. Warm air advection in a southwest flow aloft by Wednesday afternoon will cause snow levels to rise and change the snow over to rain in the lower elevations, as well as central/north central OR. The mountains will possibly see significant amounts of snow again from this next system. However, confidence is not yet high enough to issue any winter weather highlights for the mountain at this time. There will be locally breezy winds across most of the forecast area today, which will diminish this evening and then remain light through Tuesday night. After that, winds will increase again on Wednesday with the approach of the next weather system. This will especially be the case over the Cascades and the eastern/northeast mountains. These winds will be southwesterly ahead of the next upper trough that will be moving into the region, which will bring in warmer air, causing mainly rain for the lower elevations. 88 LONG TERM...Thursday through Monday...A couple of upper-level systems threaten the forecast area through the period. Guidance suggesting mainly Thursday and early Saturday look to be the best threats for area-wide precip, with the overall trend in the forecast looking to be toward colder temperatures due to the northwesterly origin of these systems. Precip type will be a challenge for Thursday`s system, as zonal to SW flow aloft head of the positively-tilting trough as it approaches from the BC coast will warm things up across the lower elevations through Thursday, but this system looks to deepen overhead as its axis approaches the forecast area, meaning cold air advection as the trough pulls in colder air from the North. NBM snow levels as a result are pretty borderline for snow in the lower elevations, with around 2000-2500 ft from central OR up through the eastern mountains, around 1000 ft for the Gorge and lower Basin, and less than 700 ft for the Yakima/Kittitas Valleys north and northwestward. Ensembles suggest, given the orientation of this system, that the SW flow ahead of this system will be most prominent across OR, resulting in the higher snow levels, while CAA will be stronger in WA, resulting in better chances for snow. QPF ensembles have trended wetter with Thursday`s system, but potential impacts will depend heavily on the environmental temperature profile across the lower elevations. The timing of precip (around early to late morning Thursday) also complicates the forecast. For now, will say that confidence is high (>70%) for another heavy snow event for the mountains, particularly for the Blues, with similar confidence for some kind of precip outside the mountains, but low confidence (<20%) on exact amounts and potential accumulations. Guidance then has the system absorbed by a preceding trough coming in from the Gulf of Alaska, further enhancing the potential for CAA across the PacNW. Ensembles in strong agreement on this, with some slight disagreement on timing, but overall focused on the early morning Saturday timeframe. Just how much this system deepens will impact the potential precip forecast, as the low centered right over the CWA, as suggested by some ensemble members, would mean a colder, drier forecast overall. That being said, the consensus across guidance on the mere presence of this system suggests moderate confidence (40-60%) in another mountain snow event, but will have to see where this system trends across future model runs to make a determination on the potential for lower-elevation precip. Will say confidence is low to moderate (20-40%) on precip chances outside the mountains Saturday, reflected by the NBM`s PoPs across our non- mountain zones. The overall trend of NW flow with some kind of troughing overhead continues beyond the weekend, meaning much of the beginning of December looks to see colder than average temperatures. Temperature spreads across ensemble members are relatively large, as expected nearly a week out, but looking like widespread lows in the teens to 20s are likely by the tail end of the extended period. Evans/74 AVIATION...12z TAFs...Expecting mostly VFR conditions through the period. Only exception would be a chance for light snow showers, primarily for RDM/BDN/PDT this morning. Any showers are expected to be of minimal impact, with accumulations light and MVFR conditions at the worst. Dry conditions will prevail during the day Monday, with mostly W/NW winds less than 10 kts and low cigs, bkn-ovc around 4-8 kft. Evans/74 && .PRELIMINARY POINT TEMPS/POPS... PDT 35 17 32 24 / 50 10 0 20 ALW 36 18 33 25 / 50 20 0 20 PSC 38 20 31 25 / 20 10 0 30 YKM 39 15 28 18 / 20 0 0 60 HRI 39 22 34 25 / 30 10 0 20 ELN 35 12 26 18 / 30 10 0 70 RDM 36 16 36 25 / 60 10 0 20 LGD 32 13 28 21 / 70 10 0 20 GCD 31 13 31 22 / 80 20 0 30 DLS 44 26 37 30 / 50 20 30 70 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Winter Weather Advisory until 4 PM PST this afternoon for ORZ050- 506. Winter Storm Warning until 4 PM PST this afternoon for ORZ502- 503. WA...Winter Storm Warning until 4 PM PST this afternoon for WAZ030. && $$ SHORT TERM...78 LONG TERM....74 AVIATION...90

000 FXUS65 KREV 281045 AFDREV Area Forecast Discussion National Weather Service Reno NV 245 AM PST Mon Nov 28 2022 .SYNOPSIS... A fast moving cold front will bring gusty winds and a chance for snow showers today then quiet weather returns for Tuesday and Wednesday. A pair of stronger storms will bring unsettled weather Thursday through the weekend with periods of gusty winds and heavy mountain snow. Travel through the Sierra will likely become difficult at times with accumulating snow possible even on the lower valley floors. && .SHORT TERM... A fast moving storm is still on track to drop southward through the Great Basin today/tonight. The track is unfavorable for significant precipitation, but scattered snow showers will likely accompany the front beginning across northeast CA and northern NV this morning and spreading southward across the eastern Sierra/western NV this afternoon/evening. Latest guidance is rather dismal on snowfall amounts, generally trace amounts up to 1/2". Some of the CAMS continue to show some banding late this afternoon into the evening which could put down locally higher amounts. So while widespread travel impacts are not anticipated, if one of these bands forms over your area, roads could become slick after sundown. Otherwise, it will be quite windy. Ridge winds were hitting 70 mph early this morning and should peak this morning around 80-90 mph. As the front approaches and gradients/mixing tighten during the day, strong surface winds will gust 35-45 mph and bring rough lake waters and impact high profile vehicles. Winds and snow showers should decrease overnight with a quiet couple of days Tue-Wed. Temperatures will be noticeably cooler Tuesday with highs topping out in the mid 30s to low 40s with hard freezes all areas Tuesday and Wednesday mornings. Hohmann .LONG TERM...Wednesday through the weekend... Attention then turns to the end of the week as latest guidance is becoming more clear on a couple of storms dropping southward from the eastern Gulf of Alaska into the western CONUS. While there are still some timing differences between the latest ECS/GEFS, the differences have lessened with the latest cluster analysis better aligned. There are fewer members that show a drier solution with with the first storm, and while confidence in QPF magnitude with the second storm is a bit lower, impactful amounts look more likely than not. The first storm is set to arrive late Wednesday night into Thursday, exiting Friday morning with the second storm over the weekend. For the first storm, winds will increase late Wednesday and really get going Thursday as 700 MB flow increases to 55-60 kts. This will easily put ridge gusts near or above 100 mph with a period of surface wind gusts 40-55 mph Thursday prior to the arrival of precipitation. This storm will be moving somewhat quickly through the region as it responds to the upstream system. However, it may have a rather robust moisture tap (based on the latest guidance) as a low pressure system and associated moisture located northeast of Hawaii around 35N/150W get entrained into the frontal zone as it moves into northern CA. WPC QPF guidance indicates 2-2.5" along the crest with 0.75-1.25" in the Tahoe Basin southward through the eastern Sierra of Mono County by the time this first storm winds down Friday morning. This would equate to a couple of feet along and immediately east of the crest with some significant snow accumulation even for the Tahoe Basin and higher elevations of Hwy 395. Significant snow is also possible for northeast CA into far northwest NV where snow levels are going to be low enough for most of the precipitation to fall as snow. For western NV from I-80 southward, a rain or rain/snow mix will likely limit accumulations, but a change over to snow Thursday night could bring some slick roads for the Friday AM commute. Right now, expect a general lull in the weather for Friday and Friday night - although it will be quite cold. The next upper low drops into northern CA Saturday and then slowly shifts east across the Great Basin Saturday night/Sunday. Snow will increase once again in the Sierra, northeast CA and northwest NV Saturday afternoon then spread to most areas by Saturday night with snow showers persisting into Sunday as conditions are likely to remain unstable underneath the passing low. Snow accumulations will be possible at all elevations with another foot (maybe two) possible in the Sierra and up to several inches for valleys. We will need another day or two to better ascertain the amounts with this second storm given a bit more spread. Hohmann && .AVIATION... * Winds aloft will peak this morning with gusts 60-70 kts across the ridges. Mountain wave turbulence and wind shear will persist today then begin to improve this evening as the trough pulls away to the east and winds aloft begin to ease. Low elevation terminal sites will see widespread westerly surface winds sustained 15-20 kts with gusts to 25-35 kts late Monday morning and lasting into the early evening hours. Winds to turn more north to northwest overnight behind the cold front, gradually weakening into Tuesday morning. * Snow showers will develop along the cold front north of a KSVE- KLOL-KWMC line by late morning, moving south into the evening. Snow showers to reach the vicinity of KTVL/KTRK/KRNO/KCXP/KMEV between 00-06z Tuesday (this evening), then rapidly clearing after 06z. Most amounts will be trace to 1/2" with a 30% chance for up to 1". Terrain obscuration is possible due to lowering CIGS/VIS in the snow showers. * Better flying conditions are on tap for Tuesday-Wednesday. Winds will begin increasing across the ridges Wednesday afternoon as the first of two winter storms approaches. Those storms will likely bring periods of strong wind and accumulating snow Thursday into the weekend. Hohmann && .REV Watches/Warnings/Advisories... NV...Lake Wind Advisory until 7 PM PST this evening for Lake Tahoe in NVZ002. Lake Wind Advisory from 10 AM this morning to 7 PM PST this evening for Pyramid Lake in NVZ004. CA...Lake Wind Advisory until 7 PM PST this evening for Lake Tahoe in CAZ072. && $$

000 FXUS66 KSTO 280925 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 125 AM PST Mon Nov 28 2022 .SYNOPSIS... A few light showers will be possible over the mountains today as a weather system moves through. Cool and dry weather Tuesday and Wednesday with near freezing minimum temperatures in the Central Valley. Widespread precipitation returns Wednesday night through the weekend. && .DISCUSSION... Quick hitting, mainly dry, system is moving south into NorCal early this morning. Satellite shows mid and high clouds spreading into the region as a cold front enters far northern California, and radar is indicating a few showers already across northwest California. Further to the south, some light fog has begun to form over the northern San Joaquin Valley. System will brush by the area today bringing cooler temperatures and a few light showers over the mountains. Some areas of fog will be possible early this morning in the Central Valley as winds diminish and RH nears saturation. Dry weather expected Tuesday into midday Wednesday ahead of the next system. This will set the stage for a couple of cold mornings with near freezing temperatures likely across the valley and areas of frost. Lows are expected to be in the upper 20s to mid 30s. Pretty consistent ensemble multi-run trends for QPF lend confidence that a more impactful system will begin to move into the region Wednesday afternoon and night bringing significant precipitation along with gusty winds. Travel impacts from accumulating snow may begin as early as Wednesday evening across the northern mountains, but will likely hold off until late Wednesday night and early Thursday morning over the northern Sierra. If these trends hold, we`ll likely be issuing Winter Storm Watches for the NorCal mountains for late-week sometime during the next 24 hours. Clusters are in overall good agreement with position of the trough on Thursday, and weak to moderate atmospheric river indicated via GEFS IVT supports continuing precipitation across the region with heavy snow in the mountains. Snow levels lower to around 2500-3500 ft in the northern mountains, and to 4000-5000 ft across the northern Sierra. 1-2 ft of snowfall accumulation will be possible over the higher elevations by sunrise Friday. && .EXTENDED DISCUSSION (Friday THROUGH Monday)... A period of cold and unsettled weather is likely across the region late this week through the weekend. First system will be winding down Friday with lingering showers continuing to provide lighter snowfall accumulations over the mountains. A second system will affect the region Saturday and Sunday bringing a second round of precipitation to NorCal. Clusters indicate greater uncertainty in the timing and location of this second trough, so confidence is not quite as high as the Wed-Fri system. GEFS also indicates a weaker IVT plume with the second system. Nevertheless, impactful snow will be possible over the mountains for the second half of the weekend. Behind that, drier weather returns early next week with potential for more near-freezing temperatures in the valley Monday and Tuesday mornings. && .AVIATION... VFR conditions over the next 24 hours with the exception of local MVFR visibility for BR/patchy FG possible 11Z to 17Z Monday in the southern Sacramento and northern San Joaquin Valleys. Locally gusty northwest to westerly winds after 18Z Monday, producing gusts to 15-20 knots, primarily at KRBL and KRDD this afternoon. The strongest winds will be over the Sierra ridgetops. Light, isolated mountain showers possible between 18Z Monday and 06Z Tuesday. && .STO WATCHES/WARNINGS/ADVISORIES...None. && $$

000 FXUS65 KMSO 281943 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1243 PM MST Mon Nov 28 2022 .DISCUSSION...Light snow is expected tonight along the I-90 corridor, particularly from Lookout Pass eastward through roughly Drummond, and points south of this corridor. This includes most of north central Idaho and the Missoula and Bitterroot valleys, Lolo Pass, and Lost Trail Pass. Snow will persist through this evening and into the overnight hours before tapering off near or about sunrise Tuesday. While snow accumulations will generally be on the lighter side (above 4500 feet: 2-6 inches, below 4500 feet: 1 to 3 inches), travel on Tuesday morning could be difficult as a result in the aforementioned locations. Tuesday into Wednesday will be mostly benign weather days, save for mountainous terrain along the Montana/Idaho border. These areas will begin to see the next round of snowfall starting Wednesday afternoon (above 5000 feet), persisting thereafter through Friday morning. This storm will make its way further over the Northern Rockies, spreading additional snowfall to both mountains and valleys alike on Thursday, with further enhancement occurring Thursday night through Friday morning as it shifts towards the Divide. What we are confident of right now is that snow will become widespread Thursday into Friday for all elevations across western Montana and north central Idaho. We also feel confident that heavy snowfall will impact terrain above 4500 feet, with the highest accumulations likely along the Montana/Idaho border, and across northwest Montana, including GNP, Marias Pass, and south towards MacDonald Pass. Storm total snowfall of up to a foot or more is expected from this system late Wednesday through early Friday, equaling between 0.75 and 1.25 inches of water equivalent. As such, difficult travel will be likely over mountain passes and in the backcountry during this time. What we are less confident about is valley snowfall amounts. A strong jet aloft with southwesterly flow often decreases the amount of snow that makes it down to valley floors, particularly in valleys such as the Bitterroot and Missoula valleys. We suspect this will be the case early on in the storm, but by late Thursday, conditions will become more favorable for widespread valley snowfall to overspread north central Idaho and western Montana valleys (if it hasn’t started before then already). A ridge of high pressure will attempt to build in behind the exiting winter storm on Saturday, which would point to dry and cold conditions along with some lingering light snow showers for northwest Montana mountains. && .AVIATION...Snow showers this evening will increase from northwest to southeast across the region with a shortwave moving through. An inch or two is all that is expected at area terminals with some MVFR and IFR conditions in the late overnight and early morning periods. Overall conditions will start improve between 29/12Z and 29/18Z. && .MSO WATCHES/WARNINGS/ADVISORIES... MT... Winter Weather Advisory from 5 PM this afternoon to 5 AM MST Tuesday for Lower Clark Fork Region. Winter Weather Advisory from 5 PM this afternoon to 5 AM MST Tuesday for Bitterroot/Sapphire Mountains... Missoula/Bitterroot Valleys. ID...Winter Weather Advisory from 4 PM this afternoon to 4 AM PST Tuesday for Northern Clearwater Mountains... Orofino/Grangeville Region...Southern Clearwater Mountains. && $$

000 FXUS65 KBOI 281641 AFDBOI Area Forecast Discussion National Weather Service Boise ID 941 AM MST Mon Nov 28 2022 .DISCUSSION...Cold upper trough is now settling southward into our area behind last night`s surface cold front that brought rain and snow. Latest radar shows the frontal band in northern Nevada still shifting south, and an area of post-frontal snow showers in southwest Idaho including the Treasure Valley and Owyhee County. We expect up to a half inch new snow in the Treasure valley and 1-2 inches in Owyhee County this morning. Snow showers should decrease this afternoon and end in all areas tonight. Then clearing and colder under northerly flow aloft. Tuesday will be the coldest day this week before upper flow backs to southwesterly Wednesday as a warm front comes in with light snow. A bigger storm is shaping up for Wednesday night through Friday as a Pacific trough with a subtropical moisture tap swings inland. Current forecast is holding up this morning. No updates at this time. && .AVIATION...Areas of low clouds and LIFR fog. Isolated IFR-LIFR snow showers, ending by 29/06z. Mountains obscured. Surface winds: variable 5-10 kt becoming W-NW 10-20 kt by 28/18z, strongest across SE OR and the Magic Valley. Winds aloft at 10kft MSL: W-NW 25-35 kt. && .PREV DISCUSSION... SHORT TERM...Today through Wednesday night...Snow showers will continue across the region today as an upper trough digs south into the Great Basin. The main band of snow that has formed along the leading edge of the upper trough will advance to the NV border by late morning. Behind this band, showers will fill in across the region through the morning as a secondary wave tracks through SE Oregon and into SW Idaho by early afternoon. The convective nature of the precipitation will make for sharp snow snowfall gradients and localized heavier snowfall amounts. Thus while general amounts of less than an inch are expected in valleys, localized accumulations of up to 2 inches will fall under the track of heavier showers. Mountains will remain favored for higher amounts with generally 3 to 6 inches of additional snow expected. Gusty winds to 30 mph will accompany the snow across higher terrain south of the Snake Plain today. Showers will diminish this evening as the trough digs southeastward. Tuesday will be dry as a weak shortwave ridge moves in from the coast. A deepening trough offshore will shift flow to the southwest and increase moisture over the area Wednesday. Precipitation will develop on Wednesday, continuing into Wednesday night. With strengthening southwest flow aloft the focus of precipitation will be over the mountains. Temperatures will be below normal through Wednesday. LONG TERM...Thursday through Monday...A cold front will stall out across the region on Thursday and Friday with significant mountain snow accumulations expected. Southwest flow aloft will likely limit snow accumulations across the Snake Basin and eastern OR. The first system will move east of the area on Friday, with generally dry conditions on Friday and Saturday. Another system will move south along the Pacific NW coast on Saturday, with snow showers redeveloping across the area Sunday into Monday. Forecast confidence is low beyond Saturday in the ensembles and the handling of this low and the evolution after that. Nonetheless, cool and unsettled conditions are likely to persist into early next week. Temperatures will remain around 5-10 degrees below normal. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...Winter Weather Advisory until 5 PM MST this afternoon IDZ011-013. Winter Weather Advisory until 11 PM MST this evening IDZ015-029-030. OR...Winter Weather Advisory until 5 PM MST this afternoon ORZ062. && $$ www.weather.gov/Boise www.facebook.com/NWSBoise www.twitter.com/NWSBoise DISCUSSION...LC AVIATION.....SA PREV SHORT TERM...DG PREV LONG TERM....KA

000 FXUS65 KLKN 281104 AFDLKN Area Forecast Discussion National Weather Service Elko NV 304 AM PST Mon Nov 28 2022 .SYNOPSIS...A frontal system will progress southward through the state today bringing accumulating snow for much of northern Nevada with less impactful snow across central Nevada through tonight. A few days of dry conditions are expected starting Tuesday before active weather including more snow arrives late Thursday into Friday. && .SHORT TERM...Today through Tuesday. Upper-level trough with attendant surface cold front will progress through the state today. A few light snow showers are currently observed on WSR-88D radar north of I-80. Short term guidance shows an expansion of snow across northern Nevada by sunrise, moving south through the morning hours. Snow amounts will be greatest across the Jarbidge Wilderness area with 2-5 inches possible along SR-225 from Wildhorse to Owyhee. 1-2 inches in surrounding valleys are expected including along US-93. Generally less than an inch is expected along I-80. Due to expected impacts, a winter weather advisory is in effect for northern Elko county and the Ruby mountains where up to 10 inches is expected. Highs will be cooler by a few degrees compared to yesterday with upper 20s to low 30s across northeastern Nevada with 40s and 50s in lower valleys in the western and southern portions of the CWA. As cloud cover and snow showers diminish overall tonight, temperatures will plummet into the single digits for most valleys, especially across Elko county. Highs Tuesday will be well below normal with most locations in the 20s in Elko county with 30s in northern Nye county. Mainly west winds will be quite gusty today as the front moves through the area with gust potential in the 20-25 mph range. A return to lower winds will occur Tuesday as the upper-trough exits the region. .LONG TERM...Tuesday night through next Sunday. A west to east flow will commence for the mid-week, which will give way to the possibility of some active weather for the latter portions of the week and into the weekend. For Wednesday, upper level low pressure is expected to be off the coast of British Columbia, Canada. There could be an isolated snow shower along the border with Idaho. Winds will be light, though some afternoon breezes are possible. Highs will be in the 30s and 40s. Quiet weather will be the rule during the overnight with lows in the teens and 20s. The aforementioned upper low is anticipated to dig slightly to the south and push near the western United States on Thursday. Light precipitation could develop during the afternoon in western Nevada. Afternoon highs will be in the 40s for the most part. Southerly winds will also develop during the late morning with gusts into the 30s possible. Light snow shower activity could spread eastward during the overnight across northern and central Nevada. Lows will be in the teens and 20s. For Friday and the upcoming weekend, additional Pacific energy tracks across Nevada. Some ensemble solutions suggest the main trough shears out across Nevada, but others keep the main trough along California as a closed low. Due to periodic cloud cover, overnight low temperatures may be near climatology for early December. But daytime temperatures stay below normal with snow levels at the valley floors. Any precipitation in the long term forecast period will be snow and therefore has the potential to be impactful. && .AVIATION...VFR conditions will prevail through the forecast period. Between 21Z Monday through 01Z Tuesday, there is a 20% of MVFR cigs at KEKO as light snow will developing in the higher terrain north of KEKO. There`s a chance of light snow making it as far west as WMC and BAM. VCSH have been added to those TAFS, however if the snow moves on station there may be brief periods of MVFR conditions. Monday after 18Z, occasional G25kts are possible at all TAF sites. && .LKN WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 4 AM PST Tuesday for Northern Elko County-Ruby Mountains and East Humboldt Range. && $$ 93/91/91