000 FXUS66 KSEW 171009 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 309 AM PDT Wed Jul 17 2019 .SYNOPSIS...A well organized for July frontal system will move through Western Washington later this afternoon into the early evening hours. A Puget Sound convergence zone is likely behind the front. An upper level trough over British Columbia will keep a mention of showers in the forecast through Thursday night. Drying trend Friday. Warming trend over the weekend as an upper level ridge builds to the east with dry weather continuing into the first part of next week. && .SHORT TERM /TODAY THROUGH FRIDAY/...Satellite imagery shows cloudy skies over Western Washington early this morning. Rain out ahead the approaching front has already reached the North Coast and portions of the Strait of Juan de Fuca. Temperatures at 3 am/10z were in the mid 50s to mid 60s. Frontal system moving down the British Columbia coastline reaching Western Washington late in the day. The system is well organized with the support of a healthy 140 knot jet over the Eastern Pacific ( it is going to be howling on top of Mount Rainier beginning later this morning ). Rain will spread over the area from northwest to southeast this morning. With the flow aloft westerly there will be a rain shadow in the Central Puget Sound. Eventually this afternoon the moist air mass will overcome the rain shadow with even the Seattle metro area getting a couple of hundredths of an inch of rain. In addition to the rain, breezy conditions developing this morning and continuing into the afternoon hours. The Olympia to Bellingham surface gradient is forecast to be around 3 mb for most of the day. Clouds and rain will keep the temperatures from warming up very much from the current readings with high only in the 60s. Front moving into the Cascades early this evening with a Puget Sound convergence zone forming quickly behind the front. Flow aloft west northwesterly which will push the convergence south into the northern portion of Seattle. Outside of the convergence zone little in the way of cool air behind the front so just a chance of showers for the remainder of the area. Lows tonight in the 50s. Convergence zone dissipating early Thursday morning. Upper level trough settling over the area during the day with most of the energy associated with the trough to the north over British Columbia. Will dry out the southern portion of Western Washington in the afternoon keeping a chance of showers from about Olympia northward. Highs will still be below normal Thursday, in the mid 60s to lower 70s. Weak upper level trough continuing to hang around Western Washington and Southern British Columbia through Friday. As the trough continues to weaken shower chances will eventually go away and cloud cover will slowly decrease to the point of partly to mostly sunny skies Friday afternoon. Highs will start to warm up a little with mid 60s to mid 70s Friday. Lows Thursday night in the 50s. .LONG TERM /SATURDAY THROUGH TUESDAY/...Extended models in good agreement with the upper level trough kicking out to the east and a weak ridge moving through the area Saturday. Four corners high beginning to build back to the northwest with another upper level trough digging off the coast Sunday through Tuesday. The trough is far enough to the west to keep any mention of showers out of the forecast. Southwesterly flow aloft with 500 mb heights rising into the lower 580 dms. Varying degrees of low level onshore flow will keep temperatures from getting too warm Sunday through Tuesday. An increase in onshore flow Tuesday will cool highs back down into the upper 60s to upper 70s from the 70s to lower to mid 80s readings Sunday and Monday. Felton && .AVIATION...Increasing westerly flow aloft today as an upper level trough and associated frontal system approach the region. A warm front draped across the coastal waters will shift onshore this morning with ceilings falling to low MVFR or occasional IFR as light precipitation spreads across the area. The mountains will be obscured. The trailing cold front will sweep across the area by early this evening. Low level onshore flow will increase behind the cold front for gusty surface winds for many area terminals this evening. Some modest improvement in ceilings possible late tonight as post-frontal showers dissipate. KSEA...Ceilings lowering to MVFR this morning as some light precip spreads into the area. Ceilings could lower to occasional IFR at times between 18Z and 00Z as a warm front pushes into the area. Surface winds S-SW 8 to 14 knots rising to 12 gusting 20 knots at times with the passage of a cold front this evening. 27 && .MARINE...A front will reach Western Washington today and south winds will pick up with that front with small craft advisory strength winds likely most waters. Westerly gales are expected behind the front tonight behind the front in the central and eastern Strait of Juan de Fuca. Onshore flow Thursday will ease Friday and then the winds over the weekend should more typical summertime diurnal sea-breezes with advisory level winds in the central and eastern strait each late afternoon and evening. 27 && .HYDROLOGY...The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated as needed until then. && .CLIMATE...With the forecast high of only 67 degrees in Seattle today will be the 4th day this month with a high in the 60s. The total number of days with highs in the 60s for the last four Julys, 3. The last time Seattle had more than 3 days with highs in the 60s in July, 2012 with 10 days. Felton && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory until 6 AM PDT Thursday for 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. Small Craft Advisory until 7 PM PDT this evening for East Entrance U.S. Waters Strait Of Juan De Fuca. Gale Warning from 7 PM this evening to 3 AM PDT Thursday for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory until 11 PM PDT this evening for Northern Inland Waters Including The San Juan Islands. Small Craft Advisory until 2 AM PDT Thursday for Admiralty Inlet. Small Craft Advisory until 7 PM PDT this evening for Puget Sound and Hood Canal. && $$ www.weather.gov/seattle

000 FXUS66 KPQR 170956 AFDPQR Area Forecast Discussion National Service Portland OR 256 AM PDT Wed Jul 17 2019 .SYNOPSIS...A frontal system will produce widespread light rain Wednesday through Thursday morning. Drier and cooler air arrives behind the front. Then warmer weather is expected for the weekend. && .SHORT TERM...Wednesday through Friday...A weak warm front will bring light rain to the coast early this morning, spreading inland later today with what looks like a secondary warm front. A trailing cold front will continue rain chances as it moves inland through Wednesday night. Rainfall will be highest along the coast and higher terrain of SW Washington and extreme north Oregon where 0.25 to 0.5 inches of rain is possible from this morning through tonight. Expect much less rain for the interior lowlands, likely less than 0.10 inches. Drier north flow moves in behind the cold front Thursday afternoon, which will allow the dew point temperatures to lower to near or below 50 Thursday night, and the minimum temperatures in the low to mid 50s, likely 10 degrees cooler than what we`ve been seeing over the last week or so. A weak shortwave trough may generate some drizzle along the north coast Friday morning, but otherwise expect dry weather Friday with clearing in the afternoon and daytime temperatures warming into the upper 70s. Not much in the way of forecast changes overall in the short term. Bowen .LONG TERM...Friday night through Tuesday...A high pressure ridge builds over northwest Oregon and Southwest Washington through Monday. This will keep conditions fairly clear and dry through the weekend with warming temperatures. Models are hesitating a little bit regarding exactly how warm it will get, so didn`t end up changing temperatures much at all. Hopefully models will get into better agreement over the next 24 hours. The ridge begins to weaken Monday night as an upper trough approaches from the northwest. However, will only see a little bit in the way of cooling by Tuesday. Overall, the long term looks dry and seasonably warm. Bowen && .AVIATION...A warm front moves into western WA this morning and brushes the north OR coast as well. A cold front follows later this afternoon and evening. Generally VFR across the area with spots of MVFR at the coast. Expect the MVFR or lower conditions to become widespread after 12Z at the coast with light rain starting shortly after. Rain tapers off tonight for the coast. Inland areas...Should see some MVFR cigs develop for a few hours this morning. Areas from KSLE southward have less cloud cover and is probably more prone to radiational cooling for stratus development. Cigs that develop will probably be in the 1500-2500 ft range based on forecast soundings. Looks like VFR should prevail inland but better chances for MVFR develop late in the afternoon and evening. KPDX AND APPROACHES...VFR prevailing with cigs in the 4000-7000 ft range. There is moderate confidence for MVFR cigs around 1500-2500 feet 12-17Z. After 00Z cigs will probably lower to 4000 ft and may occasionally lower to around 3000 ft this evening. && .MARINE...Wind have been slowly increasing overnight and is close to most model forecasts. It appears the Small Craft Advisory is on track for today so no changes to the headlines. Wind gusts between 21 and 30 kt in the northern waters expected for most of the day. The southern waters have an advisory for a shorter time period late this morning. High pressure begins to rebuild offshore on Thursday and strengthens for the weekend. This will result in a return to northerly winds through early next week. Gusts of 25-30 kt can be expected for the weekend with the strongest winds beyond 10 NM offshore. Seas start in the 3 to 4 ft range, then build to around 8 feet Thursday morning. Seas will be choppy as this system passes with the potential for square seas on Thursday morning. Seas will stay above 5 ft through the weekend. The larger seas are a product of the increased wind wave height from the short wave system that moves through Wednesday night into Thursday but also from a swell out of the NW that will be the dominant swell throughout the forecast time period. -BPhillips/mh && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory from 8 AM this morning to 5 PM PDT this afternoon for Coastal Waters from Cape Shoalwater WA to Cascade Head OR out 60 NM. Small Craft Advisory from 11 AM this morning to 2 PM PDT this afternoon for Coastal Waters from Cascade Head OR to Florence OR out 60 NM. && $$ Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. This area is commonly referred to as the forecast area.

000 FXUS66 KMFR 170951 AFDMFR Area Forecast Discussion National Weather Service Medford OR 251 AM PDT Wed Jul 17 2019 .DISCUSSION...A weak upper level trough will exit to the east today, but a second low currently over the Gulf oF Alaska will dig southeast into British Columbia tonight, pushing a weak cold front onshore and into the forecast area this evening and tonight. Chances for light showers will begin late this afternoon or evening along the coast north of Gold Beach, then will spread inland into the Umpqua Basin and the western Cascade foothills tonight. Rainfall locations and amounts should be similar to those of yesterday morning, and precipitation chances should come to an end by late Thursday morning as the front weakens and washes out over the Cascades. The center of the upper level trough will have a hard time digging any farther south than the Canadian border due to a strong ridge over the southern United States. As a result, the upper level flow will become flat and somewhat zonal over the region as it is squeezed between the two conflicting features. This will keep lower heights and slightly cooler than normal temperatures in place, and should prevent any additional chances of precipitation through the remainder of the work week. By Saturday, the trough begins to weaken and the large high to the southeast is expected to gradual drift west into the Four Corners region. Ridging is then expected to extend north along the Rockies, and with persistent troughing to the northwest, the forecast area will begin to reside under southwest flow aloft. This pattern will allow for a strengthening thermal trough and a definitive warming trend that should persist through the remainder of the forecast term. Daily highs will rise to near or slightly above normal over the weekend and into early next week, with daily rounds of afternoon marine pushes and overnight east winds, along with a day or two of the Chetco Effect along the south coast near Brookings. There is a slight chance of thunderstorms east of the Cascades Sunday afternoon, and although there are indications of increased moisture that day, there appears to be little in the way of instability or lift to get any more than very isolated convection going. There is also a question of whether or not some monsoonal moisture will be able to filter north into the area from along the western periphery of the Four Corners high next week, which could produce an increased chance for thunderstorms, especially across the East Side. Some guidance shows this possibility around Tuesday or Wednesday, but most ensemble members across all suites keep the bulk of the moisture well to the east, and therefore keep southern Oregon and northern California dry and lightning free. This could easily change over the next several forecast runs, so we will continue to watch the situation closely. -BPN && .AVIATION...For the 17/12Z TAFS...Along the coast north of Cape Blanco and in much of the rest of Coos/Douglas Counties this morning, ceilings will be a mix of MVFR/VFR. Even so, local IFR and terrain obscuration are possible. VFR returns to these areas late this morning or early this afternoon, then MVFR redevelops this evening and overnight. Patchy IFR may develop this morning near Brookings, but should dissipate by late morning. VFR will prevail elsewhere for the next 24 hours. -Spilde && .MARINE...Updated 200 PM PDT Wednesday 17 July 2019...A thermal trough along the coast will weaken today, but re-strengthen Thursday into Friday. Winds and seas hazardous to small craft this morning will ease this afternoon and tonight. However, advisory conditions will return over a broader portion of the waters Thursday afternoon into Friday night with north gales and very steep, hazardous seas south of Port Orford. Conditions should improve over the weekend, but seas will likely remain steep and choppy. -Spilde && .MFR WATCHES/WARNINGS/ADVISORIES... OR...None. CA...None. Pacific Coastal Waters...Small Craft Advisory until 11 AM PDT this morning for PZZ356-376. Small Craft Advisory from 11 AM Thursday to 5 AM PDT Sunday for PZZ350-356-370-376. Gale Warning from 11 AM Thursday to 5 AM PDT Saturday for PZZ356-376. $$

000 FXUS66 KEKA 162244 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 344 PM PDT Tue Jul 16 2019 .SYNOPSIS...Aside from patchy drizzle, dry weather is expected across northwest California through the weekend. Interior high temperatures will generally be in the 80s to low 90s across the interior, with hotter spots warming into the mid to upper 90s Wednesday and Thursday. Abundant sunshine will occur across the interior this week, while periods of marine stratus continue for most coastal areas. && .DISCUSSION...Definitely a noticeably cooler and cloudier afternoon compared to yesterday for portions of the coast, and especially some of the near-coastal river valleys of Humboldt and Del Norte county. The cooling has come thanks to a deeper marine layer and inland push of marine stratus, which has been slow to retreat even this afternoon across northwestern Humboldt County. This deeper marine push was a result of a passing mid/upper-level trough, which also brought in some cooler air aloft. This air has weakened the marine inversion enough to allow for some mixing and partial clearing of the stratus and stratocumulus in some spots, particularly around McKinleyville and Arcata. This trend may continue for a little while longer into the early evening with breezier north-northwest winds than the past few days. Otherwise, expect the stratus will fill back in tonight. Stratus is already expanding along the Mendocino coast between Fort Bragg and Point Arena, which likely portends a cloudier overnight and morning ahead for western Mendocino County. Wednesday afternoon may turn out a bit sunnier for coastal areas than today, as the marine cloudiness should be a bit shallower and thinner. Disturbances will continue to occasionally swing through the persistent Pacific Northwest trough through the end of the week. One of these will clip northwest California Wednesday night into Thursday. Model guidance supports the idea of a deepening marine layer once again, with perhaps some drizzle and fog and a more persistently cloudier day on Thursday. Heading through the weekend and into next week, little change is expected in the overall sensible weather across our region, with continued dry weather outside of any drizzle at the coast. The consensus of deterministic and long- range guidance points toward a building high pressure ridge over the western United States, while our longwave trough effectively retrogrades farther offshore to our west. This may allow temperatures inland to creep above seasonal averages, but even the hottest spots should not rise much above the mid to upper 90s. The marine layer cloudiness may become shallower, but also could tend to be more persistent at the immediate coast. Northerly winds will probably tend to be lighter after some breezier afternoons this week. /AAD && .AVIATION...Stratus, fog, and even some patchy drizzle have lingered along the Redwood coast throughout the day, with conditions at coastal terminals fluctuating between LIFR and MVFR well into the afternoon. Expect this trend to continue into the evening before conditions slide back towards more solid LIFR overnight. Recent visible satellite trends suggest CEC may see a few periods of VFR this afternoon, however localized stratus development in the vicinity of Pt Saint George is maintaining IFR cigs as the prevailing condition for the time being. There is some reason for optimism that we could see a bit more clearing at the coast on Wednesday with the low level inversion looking a little weaker and the marine layer trending a bit shallower, however confidence is on the low side as the evolution of the marine layer has proven very difficult to nail down in recent days. Meanwhile, VFR conditions are expected for the remainder of the week for inland airfields including UKI. /CB && .MARINE...Northerly winds will continue to increase through this evening before peaking overnight. Sustained wind speeds of 15 to 25 kt can be expected in many areas, with the strongest winds located near and south of Cape Mendocino and in the vicinity of Point Saint George where gusts to 30 kt can be expected. This will generate larger, steep seas, generally ranging from 6 to 9 feet with a period of 6 to 7 seconds. Winds will weaken approximately 5 kt or so Wednesday through early Thursday, but seas will remain generally elevated, particularly from Cape Mendocino southward. By Thursday afternoon, winds will increase markedly across the waters, and this will continue into the weekend. WInds will once again be strongest across the outer waters and near/south of Cape Mendocino, where sustained winds of 25 to 30 kt and gusts to 35 kt will be possible. In the more sheltered areas along the Humboldt coast, winds of 15 to 25 kt will be more common. In any case, this will drive elevated and steep seas through the weekend. In addition to the steep seas discussed above, a modest southerly swell will continue to build into the waters through roughly Thursday, with wave heights of around 3 to 4 feet and a period of around 17 or 18 seconds. While not particularly large, its presence may be felt in coves, harbor entrances and along beaches with southerly exposure. Another small mid-period swell will enter the waters from the northwest late Wednesday or early Thursday. /BRC/CB && .EKA WATCHES/WARNINGS/ADVISORIES... CA...None. NORTHWEST CALIFORNIA COASTAL WATERS...Small Craft Advisory until noon PDT Wednesday for PZZ470. Small Craft Advisory until 3 AM PDT Thursday for PZZ455. Small Craft Advisory until 9 AM PDT Thursday for PZZ475. && $$ 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 171100 AFDMTR Area Forecast Discussion National Weather Service San Francisco Bay Area 400 AM PDT Wed Jul 17 2019 .SYNOPSIS...Slight cooling is forecast for most areas today. More significant cooling is expected on Thursday and Friday, especially inland. Also, night and morning low clouds will become more widespread over the next few days. Temperatures will begin to increase by late in the weekend, but likely remain below seasonal averages through Sunday. Temperatures are then expected to warm to about average, or slightly above average, next week. && .DISCUSSION...As of 4:00 AM PDT Wednesday...The Fort Ord Profiler indicated a rapid deepening of the marine layer last evening. Based on current satellite imagery, the depth of the marine layer is likely between 1500 and 2000 feet. Low clouds have developed as far inland as the Pacheco Pass, but inland development farther to the north across the SF Bay Area has been somewhat limited. This is likely due to the fact that a moderate 4.5 mb pressure gradient remains in place from ACV to SFO. The temperature forecast for today is rather tricky. On the one hand, a deeper marine layer should mean much cooler temperatures. But on the other hand, onshore flow remains weak and the models forecast slight warming of the airmass aloft by this afternoon. The most likely outcome will be slightly cooler temperatures in most areas today. The northerly surface gradient is forecast to weaken tonight which should result in more widespread inland development of low clouds by Thursday morning. Meanwhile, an upper trough currently settling into the Pacific Northwest is forecast to sag slowly south into northern California tomorrow through Friday, resulting in further deepening of the marine layer. In addition, the models develop a low level cyclonic circulation center off the North Bay Coast by tomorrow afternoon, and then maintain a weak surface low off our coast through the end of the week. The resulting southerly low level flow along our coast will more efficiently transport marine air inland tomorrow and Friday. Thus, more significant cooling is expected over the next two days, particularly in areas that cool more readily during southerly flow such as the North Bay Valleys and Santa Cruz County. Some inland areas may cool by as much as 15 degrees by Friday and low clouds will likely linger into the afternoon hours in some areas. The upper trough to our north is forecast to move to the east by the weekend, which will allow for modest warming by Sunday. Even so, temperatures will likely remain at least slightly cooler than seasonal averages through the upcoming weekend. In the longer range, the GFS and ECMWF agree that an upper ridge will quickly amplify across the West early next week, with the ridge axis aligned from the Four Corners northward to the northern Rockies. Heights will rise as far west as California as this ridge strengthens, but a trough offshore along 140W is expected to prevent the ridge from expanding more strongly over California as had been previously forecast. Thus, the amount of inland warming next week now looks to be rather modest, with temperatures expected to warm only slightly above seasonal averages. && .AVIATION...as of 10:45 PM PDT Tuesday...Coastal stratus and fog is increasing in coverage and extending over to the East Bay. Despite a relatively shallow marine layer depth stratus advected by onshore winds have reached KSFO to KOAK and KHWD. Outside of locations in the East Bay, the coastal North Bay to San Francisco where winds remain gusty observations and the WRF model show a general decrease in surface to lower level winds thus greatly reducing the chances of any lingering low level wind shear (LLWS) for the overnight. None of the 06z tafs advertise LLWS. A mid latitude 500 mb trof passage late tonight and Wednesday morning with a corresponding cyclonic circulation at the 925 mb and 850 mb levels causes cooling and deepening of the marine layer to focus mostly from the South Bay to the north Central Coast. Elsewhere 925 mb temperatures warm by a few degrees, which should keep the marine layer depth either unchanged or compress it a little. Best chance for marine based clouds and fog will be along the coast over to the East Bay and South Bay southward along the north Central Coast tonight and Wednesday morning, VFR to the north and inland. Sufficient mixing is forecast Wednesday to lift ceilings and visibilities on the coast while VFR continues inland. A weak southerly wind reversal may develop along the north Central Coast Wednesday. The 06z tafs wind forecasts mostly depart from statistical guidance later in the forecast period based on reasoning described above. Vicinity of KSFO...West wind still gusting to near 25 knots. VFR turned to MVFR ceiling due to advection of stratus by a west wind earlier this evening. 06z taf adjusted for recent change, but not certain the stratus ceiling will hold all night as the marine layer depth probably remains unchanged and the ACV-SFO pressure gradient is nearing 6 mb, a stronger northerly coastal wind could end up drawing the stratus back to the ocean overnight. Thus KSFO marginal MVFR ceiling with tendency toward VFR return Wednesday morning probably early, but timing this is low confidence. SFO Bridge Approach...Similar to KSFO. Monterey Bay Terminals...Stratus redeveloped a little quicker than earlier forecast. Patchy drizzle could develop tonight. VFR returns Wednesday morning with winds becoming southerly during the late morning and afternoon. && .MARINE...As of 2:58 AM PDT Wednesday...High pressure will remain in place about 1100 miles west of Point Arena. Northwest winds will decrease as a ridge builds into the pacific Northwest coast. Light long period southerly swell will continue to be the dominant swell group through at least Thursday. && .MTR WATCHES/WARNINGS/ADVISORIES... .Tday...SCA...Mry Bay until 3 AM SCA...Pt Reyes to Pigeon Pt 0-10 nm until 3 AM SCA...Pigeon Pt to Pt Pinos 0-10 nm until 3 AM SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm until 3 AM SCA...Pt Arena to Pigeon Pt 10-60 nm SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm SCA...Pt Arena to Pt Reyes 0-10 nm && $$ PUBLIC FORECAST: Dykema AVIATION: Canepa MARINE: W Pi 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 170949 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 249 AM PDT Wed Jul 17 2019 .SYNOPSIS... The next system is moving into the region bringing an increase in clouds. Widespread breezy to windy conditions are expected Wednesday into Thursday. Spotty showers will continue in the northern mountains through the work week. Expect a cold morning Friday before hot and dry weather returns by Sunday into early next week. && .DISCUSSION... ...Gusty winds and low RH values Thursday to elevate fire weather concerns... ...Colder morning lows Friday morning... Today through early Friday morning: The next 2 days will focus on an unseasonably very strong upper level jet. A closed low will move into Canada late today, with most of the strong dynamics remaining north of the border. However, a 150kt jet (which is about 10 kts stronger than what models were showing 2 days ago) will push into the region starting this morning. It will nose into the Cascades this morning and then sit over northern and central WA/northern ID this afternoon through most of Thursday before it starts to exit/sag south late Thursday night/early Friday morning. Breezy to at times windy conditions are expected across the region today and Thursday. Today`s winds will focus more in the Cascades, Wenatchee area, Waterville Plateau into the Columbia Basin, Palouse and Spokane area. Thursday`s winds will be across the Columbia Basin, Spokane area and Palouse as well as most of the Idaho Panhandle. Widespread gusts 25 to 35 mph is expected. Brief locally higher gusts is quite possible...40 to 50 mph. This will raise some fire weather concerns, especially on Thursday as the relative humidity values drop into the upper teens to mid 20s for most of the WA valleys. However most fuels are not cured/dried out enough to warrant highlights, as of this morning. We do have the potential to see sprinkles or light rain showers today across the Cascades and northern WA/ID. Have added a slight chance of thunderstorms along the Canadian border in NE WA given models showing some instability. Temperatures will continue to be about 5-10 degrees below average for this time of the year. Highs in the valleys will be in the 70s to low 80s, and lows will be in the upper 40s to mid 50s. Of particular note will be the unseasonably cool temperatures by Friday morning. Very dry air moving in coupled with mostly clear skies will lead to what will feel like cold temperatures across the Cascades, and the colder valleys of northern WA and ID. Lows in the lower 40s...with mid to upper 30s in the Cascade mountains is expected. /Nisbet Friday through Tuesday: Cool morning temperatures can be expected under a low pressure system into Saturday morning. Forecast lows in the Cascades for instance show higher terrain lows below 40 degrees. Areas such as the Pacific Crest Trail and campgrounds in the Northern Cascade mountains should be ready for another chilly night Friday into Saturday morning. Friday`s potential instability will produce showers in the northern mountains. At this point there is not a strong lifting focus to produce widespread thunderstorms but there will be a possibility of thunder near the Canadian Border for late afternoon/early evening thunder. Winds will be much weaker Friday onward. The GFS is the outlier as other deterministic models and ensembles say Saturday will be mostly dry as high pressure builds into the area starting our warm-up for the weekend into next week. So we are drying the forecast Saturday onward and temperatures will finally be above normal come Monday as a more Summer like pattern and high pressure ridge axis set up to the east over Montana with south to southwest flow aloft. Temperatures will be well into the 90s the beginning of next week. There are some hints in the deterministic models that moisture from the south will ride up the west side of the ridge which can produce some thunderstorms. Right now confidence is generally low that this will occur but bears watching over the coming days. TC && .AVIATION... 06Z TAFS: This evening will start off quiet, with mostly clear to partly cloudy skies. However another system pushes in overnight into Wednesday, thickening clouds again and increasing the threat of showers throughout the day Wednesday. In the morning it may be little more than sprinkles, but more hit-and-miss showers are possible by Tuesday afternoon, after 18-20Z. The system will also lead to broader increase in winds, with gusts in the 20-30kt range possible. /Cote` && .PRELIMINARY POINT TEMPS/POPS... Spokane 76 54 75 47 74 48 / 10 10 0 0 0 0 Coeur d`Alene 74 53 74 46 74 47 / 10 20 0 0 0 0 Pullman 75 52 74 45 72 45 / 0 0 0 0 0 0 Lewiston 86 61 82 53 80 54 / 0 0 0 0 0 0 Colville 78 44 76 40 76 40 / 20 20 0 0 10 10 Sandpoint 70 51 72 45 71 45 / 30 40 20 0 0 0 Kellogg 69 55 70 50 70 49 / 10 40 20 0 0 0 Moses Lake 82 55 81 48 80 51 / 0 0 0 0 0 0 Wenatchee 77 58 76 53 77 55 / 10 10 0 0 0 0 Omak 80 53 78 50 78 52 / 10 10 0 0 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$

000 FXUS66 KPDT 171040 AAA AFDPDT Area Forecast Discussion...Updated National Weather Service Pendleton OR 340 AM PDT Wed Jul 17 2019 Updated aviation discussion .SHORT TERM...Today through Friday. Zonal flow will be present through the end of the work week keeping temperatures at or below normal. While no strong shortwaves are expected to affect the area, scattered showers will remain possible along the crests of the Cascades beginning this afternoon and will continue into Thursday morning. A few stray showers will also be possible in the Blue Mountains late this evening although chances remain very low. One final shortwave is expected to pass north of the forecast area through the day on Friday bringing rather cool temperatures for this time of year. With limited moisture, precipitation is not expected. Gusty winds will be possible both this afternoon/evening as well as again on Thursday afternoon/evening. While winds will remain below advisory criteria, a few gusts between 25-35mph are possible through the Columbia River Gorge and parts of the Kittitas Valley. Richards .LONG TERM...Friday night through Wednesday. Models in good agreement with overall pattern. Westerly flow will dominate the area through Saturday as an elongated upper level trough slowly makes its way through the region. A building upper level ridge and an upper level low west of Vancouver Island will result in general south to southwest upper level flow over the region through the remainder of the extend period. The GFS shows a more amplified pattern producing a more southerly component. This would allow enough mid level moisture for isolated late afternoon/early evening convection beginning Tuesday. The ECMWF shows a less amplified pattern which keeps the flow more southwesterly. This would keep the convective threat east of our CWA. Most of the GFS Ensemble members indicate a more convective pattern too. At this time will only go with a few afternoon/evening buildups Tuesday and Wednesday. However, this pattern will need to be closely monitored as the onset of such a pattern could produce some high-based, dry thunderstorms by the middle of next week. Temperatures will warm quickly to above normal Sunday and remain above normal through the rest of the period. Earle && .AVIATION...12Z TAFs...VFR conditions will prevail through the period. Ceilings will increase through the day as a weak system moves through the region. However, ceilings are expected to remain above 7000 feet. Cloud cover is expected to decrease overnight as the system exits the region. Winds will increase to 10-20 kts with higher afternoon and evening gusts. Winds are expected to decrease to 12 kts are less by late evening. Earle && .PRELIMINARY POINT TEMPS/POPS... PDT 83 56 79 48 / 10 10 10 0 ALW 84 60 83 53 / 10 20 20 0 PSC 87 60 84 54 / 10 10 0 0 YKM 82 53 79 49 / 10 10 0 0 HRI 85 59 83 52 / 10 10 0 0 ELN 72 52 71 50 / 20 20 0 0 RDM 81 49 79 44 / 0 10 10 0 LGD 81 54 76 48 / 10 20 20 0 GCD 83 53 81 47 / 10 10 10 0 DLS 77 60 77 53 / 10 20 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 75/81/81

000 FXUS65 KREV 170911 AFDREV Area Forecast Discussion National Weather Service Reno NV 211 AM PDT Wed Jul 17 2019 .SYNOPSIS... Quiet weather conditions are expected for the rest of this week with seasonable temperatures, typical late day winds, and no thunderstorms. That could change next week as high pressure over the Desert Southwest builds, allowing some moisture to work northward into our region. && .SHORT TERM... The only change this morning was to warm temperatures up a few degrees across western NV today and Thursday. The upper trough that brushed our region Tuesday and brought the slight cool down will lift out of the region today. This will allow for heights to rise and temperatures to rebound rather quickly. 700 MB temperatures will climb to between 14-15C which corresponds to mid-upper 90s across lower elevations from I-80 south and low 80s for the Sierra valleys today and Thursday. As the jet stream dips southward a bit toward the Oregon border Friday, temperatures aloft cool some. The change may allow temperatures to cool a degree or two Friday afternoon - probably not enough to notice. Model soundings continue to show it too dry and stable for any thunderstorms. In fact, there is a pretty decent capping inversion in the mid levels. So despite the heating, any convection would be limited to a few cumulus/shallow buildups along the eastern Sierra south of Highway 50 and in the Lassen County convergence zone north of Susanville Thursday and Friday. Winds will be light except for the typical afternoon/evening breezes with most peak gusts remaining around 25 mph. LXVIII .LONG TERM...Saturday through Tuesday... The extended forecast period is getting more interesting as most models and ensemble members now agree that a ridge will begin building over the southwestern U.S. late this week and into the weekend. That will bring changes to the forecast for our area. Some of these changes have already been incorporated into the forecast. Other adjustments may be needed as we get closer to the weekend and into early next week as we see how the pattern evolves. Saturday still looks rather quiet...but we do begin to see high temperatures warming as the zonal flow over the region begins to shift to the south-southwest with the building ridge. That would allow highs to rise. Some forecast soundings even hint at the start of an influx of mid-level moisture as early as Saturday. For now we have left convection out of the forecast. As we move into Sunday and beyond the model simulations are in better agreement that mid-level moisture begins to make its way farther north into the forecast area. Along with this increase in moisture we see increased temperatures with the ridge axis to the east. These four-corners highs often bode well for our area getting back in on thunderstorm development. This situation should be no different. The first day of convection can be a dry thunderstorm day as instability is increased along with mid-level moisture...but moisture is too sparse for precipitation to make it to the surface. So...we included a slight chance of just thunder for Sunday across parts of the southern half of the forecast area. That may raise fire weather concerns. By Monday and Tuesday moisture is increasing. That...along with increased high temperatures and low-to mid-level instability... should allow for increasing coverage of thunderstorms and a few showers. We have capped the POPs at very low end chances for now...but this may need to be increased as the situation evolves. Highs each day will be near or slightly above climatological averages. By the latter half of July we are into the warmest period of the year with highs typically in the mid to upper 90s for the lower valleys and 80s in the Sierra valleys. XX && .AVIATION... VFR conditions should continue for the rest of this week and into the early part of the coming weekend. Winds are likely to be typical for summer with late afternoon/early evening gusts in the range of 20-25 kts. Some late afternoon turbulence due to surface heating is also expected. Thunderstorms are not expected into the early part of the weekend...but a return to a pattern more conducive to thunderstorm development is becoming a much stronger possibility as we move into Sunday and beyond. REV && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$ For more information from the National Weather Service visit... http://weather.gov/reno

000 FXUS66 KSTO 171030 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 330 AM PDT Wed Jul 17 2019 .SYNOPSIS... Dry weather with seasonably hot temperatures continue, gradually cooling by late this week. Breezy winds through the Delta and over the Sierra crest at times. && .DISCUSSION... Not much change in the overall pattern as a weak trough lingers along the West Coast into the weekend. Therefore, dry conditions and seasonably hot temperatures will continue. Temperatures in the Delta Breeze influenced areas will vary slightly day-to-day depending on the depth of the marine layer and strength of onshore flow. && .EXTENDED DISCUSSION (Sunday THROUGH Wednesday)... Current extended forecast remains dry as Norcal remains under the western portion of a strong high pressure ridge over the western U.S. Should see fairly stable conditions under upper southwest flow between this high pressure ridge and troughing over the eastern Pacific. Operational GFS has been hinting at bringing monsoon moisture up the Sierra in more southerly flow for some possible Sierra thunderstorms early next week. GEFS ensemble members not really backing up this idea at this time so have kept Sierra afternoon thunderstorms out of the forecast. With Norcal being under the western fringe of the western U.S. ridge, the CWA will not see the full effects of subsidence warming and as a result, daytime temperatures through the extended will stay near or just slightly above normal with no heat wave expected. Winds should remain fairly light except for occasionally breezy through the delta and over the Sierra crest. && .AVIATION... VFR conditions next 24 hours. Southwest wind gusts 20-30 kts vicinity Delta; otherwise, sustained winds generally below 15 knots. && .STO WATCHES/WARNINGS/ADVISORIES...None. && $$

000 FXUS65 KMSO 170957 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 357 AM MDT Wed Jul 17 2019 .DISCUSSION...An upper level disturbance will bring an increase of cloud cover and chances for showers across northwest Montana this afternoon and evening. A westerly jet stream will nudge across the Northern Rockies this afternoon with blustery westerly winds developing for the afternoon and evening hours. Winds will further increase during the day Thursday, with the strongest winds expected over northwest Montana, especially near the Continental Divide, where wind gusts up to 50 mph will be possible across mountain passes in Glacier National Park. Those planning to recreate on area lakes should be prepared for choppy conditions, especially during the day Thursday. A relatively cool trough of low pressure will drop southward out of British Columbia and Alberta into northwest Montana Friday. Little to no precipitation is expected with this system. As this system exits the area Friday night, cool overnight temperatures are expected with higher mountain valleys potentially seeing local areas of frost. Model guidance continues to come into better agreement with the depiction of a large area of high pressure amplifying across the western U.S. this weekend into early next week. The warmest temperatures of the summer could take place early next week, as highs across western Montana valleys soar into the mid 90s and lower elevations of north central Idaho reach the century mark. && .AVIATION... Patchy valley fog this morning across northwest Montana, including terminal KGPI, will give way to ceilings mostly above terrain features across most of the Northern Rockies through 18/0000Z. Very low ceilings and visibility due to fog at KGPI will exist through 17/1400Z. After 17/1800Z winds will intensify across the Northern Rockies, with gusts to 25 knots possible at all major terminals, including KMSO, KGPI, KBTM, KSMN. Winds will subside after 18/0200Z. Rain showers will spread across northwest and west central Montana beginning 17/2100Z, which may bring down ceilings to below mountain top elevation near KGPI and KMSO. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

583 FXUS65 KBOI 170901 AFDBOI Area Forecast Discussion National Weather Service Boise ID 301 AM MDT Wed Jul 17 2019 .SHORT TERM...Today through Saturday...A nearly zonal flow over the area will bring quiet conditions over the area for the next few days. The pressure gradient across the area will increase Thursday and Friday due to low pressure moving across southern Canada. This gradient will result in periods of gusty afternoon wind. The strongest winds appear to be over south- central Idaho, including the area between Mountain Home and east of Twin Falls. Temperatures will be similar each day, though small fluctuations are expected. Overall, temperatures should remain 5 to 10 degrees below normal. .LONG TERM...Saturday night through Wednesday...A very warm high pressure ridge will amplify over the western U.S., raising temperatures in our area from near normal on Sunday to 5-10 degrees above normal Monday through Wednesday. Monsoon moisture is expected to drift far enough north by Wednesday for isolated afternoon and evening thunderstorms over the central Idaho mountains and the higher terrain near the Idaho-Nevada border. && .AVIATION...VFR. Mostly clear skies. Surface winds variable less than 10 kts becoming west-northwest 10-15 kts after 21z. Winds aloft at 10k feet MSL west-southwest 20-30 kts. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise www.facebook.com/NWSBoise www.twitter.com/NWSBoise SHORT TERM...KB LONG TERM....JT AVIATION.....JT

000 FXUS65 KLKN 170844 AFDLKN Area Forecast Discussion National Weather Service Elko NV 144 AM PDT Wed Jul 17 2019 .SYNOPSIS...Very warm temperatures and dry conditions will prevail through the upcoming weekend. Opportunities for showers and thunderstorms return early next week as monsoon moisture tries to filter into the region. && .SHORT TERM...Today through Thursday. Temperatures in the 90s along with dry conditions under mostly clear skies will persist through Thursday as zonal flow takes hold. West to southwest winds will be gusty at times in the afternoon but will not be an impactful issue. .LONG TERM...Thursday night through next Tuesday. Weak flow aloft over the CWA Friday and Saturday with continued storm-free conditions along with slightly above normal temperatures. On Sunday high pressure will build up from the four corners region, which will result in even warmer temperatures along with a trend of increasing moisture. Models continue to gradually increase moisture and instability over the CWA on Monday, with a slight chance of thunderstorms setting up over portions of central NV highland areas. Moisture under the gradually building ridge increases next Tuesday which may result in more widespread showers and thunderstorms over central NV and up into portions of northern NV. At this time instability for next Tuesday looks relatively weak while PWs and surface dew points are very high. This suggests mostly cloudy with some isolated thunderstorms. Any storms that do develop however may have some decent rains. && .AVIATION...VFR conditions will continue through early Thursday morning and beyond. Southwest to west breezes will gust into the 18 to 26 kt range this Wednesday afternoon. Note: AMD NOT SKED for KBAM until further notice due to missing sky conditions from automated WX station. && .FIRE WEATHER...Dry conditions with very warm temperatures will persist through the weekend. Expect critically low daytime relative humidity each day with increasingly poor overnight recoveries through the weekend. Winds will be gusty each afternoon from the west and southwest but will stay below critical thresholds. Dry thunderstorm chances increase early next week as monsoon moisture tries to make its way back into the state. && .LKN WATCHES/WARNINGS/ADVISORIES... None. && $$ 93/96/96/93