195 FXUS66 KSEW 032126 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 226 PM PDT Thu Apr 3 2025 .SYNOPSIS...Upper ridging over the Pacific Northwest will bring dry weather through Saturday. A front will move through Sunday for increasing rain. Troughing early next week will bring showers and cooler temperatures. && .SHORT TERM /TONIGHT THROUGH SUNDAY/...A mix of clouds and sunshine this afternoon with temperatures in the 50s. An upper ridge will continue to build over Western Washington into Friday for dry conditions. Clear skies tonight, along with lighter winds, may result in areas of fog, mainly for Olympia southwards, as well as along the Chehalis River Valley. In addition, temperatures are expected to drop into the low to mid 30s for these aforementioned areas. This may result in frost development, especially in areas away from the water where clear skies continue. A Frost Advisory has been issued for these zones tonight into early Friday morning. High clouds may be around on Friday at times, but mostly sunny conditions are expected. A bit more in the way of high clouds on Saturday as a frontal system moves towards Western Washington. High temperatures in the 60s on Friday will warm into the upper 60s and low 70s for some areas on Saturday. Rain chances will increase Saturday night, initially along the Olympic Peninsula, before rain moves into Puget Sound during the day on Sunday. Temperatures on Sunday will be about 10 degrees cooler in the mid to upper 50s. .LONG TERM /MONDAY THROUGH THURSDAY/...Troughing will continue over Western Washington early next week. This will result in continued unsettled weather, at least through early Wednesday. Showers will be around during this period, and can`t rule out a thunderstorm either Monday afternoon (NBM probabilities around 10-20%). Snow levels will drop near 3500 to 4500 feet later Monday into early Wednesday, which may result in light to moderate snow accumulations for higher elevations. Ensembles suggest that ridging may try to build into the interior Pacific Northwest on Wednesday. However, due to continued troughing offshore, kept NBM probabilities of precip at this point, resulting in continued shower chances. Temperatures will be near to slightly below normal early next week. JD && .AVIATION...North winds aloft as an upper level ridge begins to move eastward towards western Washington. A scattered cumulus field has allowed for VFR conditions to prevail across the area. VFR conditions will continue through tonight as cloud cover continues to break up. Some high clouds will move in overnight, which may limit more widespread fog development tonight into early Monday morning. The best chances for fog development look to be around the south sound and Chehalis valley, through other river valleys and fog-prone coastal areas may see some patchy fog early Monday morning. Patchy frost may also limit fog development around OLM and southward. All in all, any fog that develops will be short-lived and VFR conditions should continue into Friday. Light north-northwesterly winds will turn to northeasterly this evening before becoming calm overnight. Winds again tomorrow will be light northwesterly (5 kt or less). KSEA...VFR conditions prevail through the majority of the TAF period. There is a 15-25% chance of seeing some low clouds/fog at the terminal between around 12-18Z Friday, through this will likely be short-lived if it does develop. There are several limiting factors (mentioned above) that decrease forecast confidence in fog. Northwest winds will veer to northeast this evening (up to 5 kt), becoming light and variable/easterly (5 kt or less) to calm overnight. Winds will resume as north/northwesterly, up to 5 kt, during the day Friday. 62 && .MARINE...Broad high pressure over the northeast Pacific will remain in place through Sunday, continuing the period of light winds and seas. The next frontal system will move through the waters on Sunday, bringing a quick round of breezy winds which may require headlines. Additional systems look to traverse the area waters early next week, keeping breezy conditions in the forecast. Combined seas 3 to 5 feet through the rest of the week and into the weekend. Seas will start to gradually build upwards Saturday night into Sunday, reaching 10 to 13 feet Sunday and remaining in the 8 to 12 ft range through early next week. 62 && .HYDROLOGY...No river flooding is expected over the next 7 days. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Frost Advisory from midnight tonight to 9 AM PDT Friday for Lowlands of Lewis and Southern Thurston Counties-Middle Chehalis River Valley-Olympia and Southern Puget Sound. PZ...None. && $$

559 FXUS66 KPQR 032127 AAA AFDPQR Area Forecast Discussion National Weather Service Portland OR 226 PM PDT Thu Apr 3 2025 .SYNOPSIS...Mild and dry across the area today with temps near seasonal normals in the upper 50s. Clearing skies will pave the way for chilly temps and potential widespread frost formation tonight into Friday morning. Warm and dry conditions expected Friday and Saturday with highs in the 70s in the interior valleys. Cooler and more showery weather returns Sunday into early next week. && .SHORT TERM...Now through Saturday Night...Showers have all but ended throughout the region, and a period of shortwave ridging is expected for the next few days. Drier and increasingly warm daytime temperatures through Saturday. High temperatures are around seasonable today, with afternoon highs in the mid 50s for most lowland areas. This climbs up to around 70 Friday, and further to the low/mid 70s Saturday afternoon (the warmest day of the week). Chances of lowland temperatures breaking 75 degrees on Saturday are under 10% for most areas, with slightly higher chance at 30% for the Portland metro due to urban heat island effect. Coastal areas will remain more mild as they retain a marine layer influence through Saturday. Afterwards, temperatures drop as we see a pattern change back to showery seasonable weather on Sunday. However, in the immediate term, tonight (Thursday night) sees a good chance for frost formation throughout the region before heating really picks up. With relatively clear skies and temperatures dropping to the mid 30s, radiational cooling will be fairly strong and much of the area will likely see frost concerns tonight as surface temperatures likely will be several degrees cooler. The Frost Advisory has been extended to most of the Cascades foothills as well as the Coast Range Valleys, with much of these areas seeing temperatures between 33-36 tonight. Portland metro remains out of the Frost Advisory as temps remain just a hair too warm, closer to 37-39 tonight. /JLiu .LONG TERM...Sunday through Wednesday...Medium range continues to show good agreement on the arrival of the next trough on Sunday as the upper level ridge shifts east of the Cascades. As a result, the forecast has trended cooler and wetter for Sunday with increasing precipitation chances and NBM 50th percentile temperature guidance residing in the low to mid 60s in the interior lowlands. Expect a benign pattern characterized by mild temperatures and showery weather to persist during the first half of next week as ensemble clusters depict upper level troughing over the NE Pacific and broad onshore flow across the Pacific Northwest. Models do not indicate any significant weather impacts across the region within the next seven days. /CB && .AVIATION...Widespread VFR across the airspace as high pressure continues to build over the Pacific Northwest. Which will bring dry conditions and slowly clearing skies. These conditions are expected to persist through the TAF period. Variable winds less than 10 kt. Clearing skies, moist ground and near freezing temperatures overnight could result in some frost development. This is not expected to be impactful, but exposed surfaces could see some very light accumulations within the Willamette Valley. Best time for frost accumulation will be from 07Z through 16Z Friday. KAST anemometer is still inoperative. Therefore, TAFs limited to CIG and VIS. PDX AND APPROACHES...Predominately VFR conditions through the TAF period with variable winds less than 10 kt. /42 && .MARINE...High pressure will settle over the region through the remainder of the week. This will bring northerly winds around 5 to 10 kt to all waters. As high pressure moves inland, look for a more offshore flow pattern to develop on Friday, with winds becoming southerly ahead of an approaching system by Saturday. Seas will generally be 3 to 5 ft through Saturday. The next frontal arrives Saturday evening/Sunday. As the front approaches, winds and seas will build. Expect Small Craft Advisory gusts across all waters by Sunday night and they are expect to increase into Monday. A second, stronger front late Monday/early Tuesday, will bring a 25% probability for Gale-force gusts up to 35 kt on Monday. As the front approaches the waters, seas will build towards 11 to 13 ft on Sunday as a fresh westerly swell pushes into the waters. /42 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Frost Advisory from midnight tonight to 9 AM PDT Friday for ORZ104-105-109-113>118-121-123>125. WA...Frost Advisory from midnight tonight to 9 AM PDT Friday for WAZ205-208. PZ...None. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

687 FXUS66 KMFR 032322 AFDMFR Area Forecast Discussion National Weather Service Medford OR 422 PM PDT Thu Apr 3 2025 ...Updated AVIATION discussion for 00Z TAFs... .DISCUSSION... KMAX is picking up on some echos in Modoc County this afternoon as this upper level wave begins to exit the region. There are also plenty of fair weather cumulus clouds covering locations west of the Cascades this afternoon. Skies are anticipated to clear out even further tonight with temperatures dropping down towards freezing. We should see plenty of frost across the forecast area and we did insert that into the gridded forecast. Given that these low temperatures are pretty typical for this time of year, and it is still early in the growing season, we opted to not issue a frost advisory for any of our forecast zones for tonight. Temperatures will likely hit the freezing mark in the Illinois and Rogue valleys, although remains a few degrees above freezing on the Umpqua Basin. There was some question of fog building into the valleys, but dew points appear to be a little too low as we mix out this afternoon. As high pressure remains in control, Friday and Saturday will be quiet and rather typical for Spring weather in southern Oregon and northern California. Highs will push into the upper 60`s and lower 70`s with clear skies. Things begin to change up on Sunday with warm moist air pushing in ahead of a cold front or one could analyze it as an occluded front. In any case, models are very confident this front will hit the Oregon coast, the only question is the exact timing. Some data shows the front arriving as early as 5 am Sunday morning whereas most data shows the front arriving later Sunday evening perhaps into Sunday night. In any case, this band of rain will arrive with snow levels starting around 8000 feet before falling to 4000 feet behind the front, a pretty drastic change in snow levels. Snow accumulation will be minimal with most of the precipitation falling while snow levels are 6000+ feet. The only impact here is the rain continuing to cause issues with landslides around the old Archie Creek burnscar on highway 138. Total QPF is under 1 inch with the exception of the coastal range in Curry County with up to 2 inches falling there. This rain should fall over a 36 hour timespan and shouldn`t produce widespread impacts. Conditions will trend cooler around Tuesday with the probability of precipitation around 10 to 50 percent. Those higher probabilities will be in the northern sections of our forecast zone and the lower probabilities in the northern portions of California. Precipitation will again be light and not impactful through this time. From Wednesday into Friday, conditions look wet and it appears we`ll be under warmer southwest flow. Impacts are anticipated to be minor, although we`ll have to keep an eye on rivers or streams starting to run higher. -Smith && .AVIATION...04/00Z TAFs...Northerly flow aloft is continuing to bring scattered clouds, especially over Douglas and Lake counties. Showers are minimal on radar, so VFR levels are expected to prevail for most areas through the TAF period. A period of marine stratus is possible over North Bend early Friday morning, and has been included in the forecast. Guidance also shows weak fog signals for Roseburg and Medford early Friday morning, but there is not enough confidence in those outcomes to add them to the forecast. -TAD && .MARINE...Updated 215 PM Thursday, April 2, 2025...Seas are expected to be around 6 to 9 feet at 9 seconds today with north to northwest winds generally in the 10-25 kt range, strongest to the south. As a result, a Small Craft Advisory is in effect today out to 20 NM from shore off Cape Blanco, and extending to 60 NM from shore off Pt. St. George. A period of improving conditions is expected tomorrow morning through Saturday. Thereafter, a building long period (17-20 seconds) west swell is anticipated on Sunday, and this will likely lead to steep seas and hazardous conditions over the waters. This is looking to continue into the start of next week as well. -Guerrero/Hermansen && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 3 AM PDT Friday for PZZ356-376. && $$

982 FXUS66 KEKA 032151 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 251 PM PDT Thu Apr 3 2025 .SYNOPSIS...Warm, dry, and calm weather will build through Saturday. Another quick round of light to moderate rain is expected around Sunday. && .DISCUSSION... KEY MESSAGES: -Warm, calm, and dry weather through Saturday: interior highs in the upper 70s. Cool temperatures at night: isolated interior frost. -Moderate south wind and rain return around Sunday: minimal impacts expected. WEATHER PATTERN OVERVIEW: A narrow but slow moving ridge has started to drape across the area today and will continue through Saturday. The front edge of the ridge moving onshore has allowed for continued drying and clearing conditions all across the area with interior highs increasing into the 60s. Along shore, surface high pressure aligning with the coast has sustained moderate northerly winds gusting up to 25 kts in exposed areas. Clear skies may allow for patchy interior frost tonight. Though lows will likely be higher than lass night, less fog and cloud cover will likely allow for more efficient cooling. NBM places a 60 to 80% chance of lows at least as low as 36 throughout northeast Mendocino Country and eastern Humboldt. WArm, calm, and dry conditions will continue to build through Saturday. By Saturday, the warmest interior valleys will most likely see highs between 75 and 79 with little chance (10%) of highs reaching above 80). Along the coast, northerly wind will decrease but gentle onshore flow and an enhanced inversion will likely allow for a sporadic, diurnally driven marine layer to form just along shore. There is high model confidence that an upper level shortwave will sweep past the area around Sunday. This wave will most likely bring a short lived period of moderate southerly wind and rain. Rain will be mostly focused in Humboldt and Del Norte. 0.5 to 2.0 inches of rain is most likely over 24 hours, dependent upon elevation, with minimal expected impacts. Snow levels most likely above 4500 feet will greatly limit any winter weather impacts. Wind will most likely be similarly moderate with gusts 20 to 30 mph. Warmer and dryer weather is most likely to quickly return after the rain. FORECAST CONFIDENCE AND DEVIATIONS: There is relatively high forecast confidence for the next 7 days. In the short term, the greatest uncertainty is related to nighttime frost. The extent of frost will largely be determined by very localized changes in moisture and exposure. In either case, the chances of frost wills steadily decrease into the weekend. There is some uncertainty regarding this weekend`s rain system, and model guidance has steadily gotten wetter over the past few runs. That said, there is little potential for much more than a moderate event. There is a contingent of model members (about 15%) which show higher rain potential around 3.0 inches, but the vast majority suggest a lower end rain event. Essentially now ensemble members show wind gusts over 45 mph. /JHW && .AVIATION...Gusty N-NW winds expected this afternoon as high pressure ridge builds into the eastern Pacific, tightening the coastal pressure gradient. So far winds have been laminar with sustained speeds around 15 kt. Turbulence and boundary layer mixing increases later this afternoon or early evening and should yield more gustiness with peaks around 25 to 30 kts. Highest HREF probabilities for gusts to 35 kt are at KCEC by 5 or 6 PM; about a 20% chance. Also, the downscaled ECMWF ensemble mean indicates peak gusts just under 40 mph for KCEC while KACV is just shy of 30 mph. North winds will decouple and shift E-NE by late evening as a thermal trough pushes offshore. Some misty air conditions may develop at coastal terminals before drying easterly winds develop overnight. Gusty NE and E winds are expected over the ridges and channeled terrain overnight. HREF probabilities for low level wind shear over the terminals is 20% at most, but much higher over Lake, northern Mendocino, southern Humboldt and much Trinity. Shallow mountain wave turbulence may occur as the strong east to northeast winds intersect the NW-SE oriented ridges early Friday morning. Otherwise, VFR is expected except for shallow fog and low clouds in valleys where winds go calm. DB && .MARINE...Fresh to moderate northerly breezes will persist through this evening. Strongest north winds (20-25kt) are forecast to continue just outside 10NM, but will extend into portions of the inner waters this evening in response to land mass heating. A couple of weak expansion fans, one around and just downwind of Pt St George and another in the lee of Cape Mendocino, will yield a 30 to 50% chance for gale force gusts to 35 kt this afternoon and evening. The persistent northerlies will continue to produce short period waves from 6 to 8 ft tonight, highest in the outer waters. Thus, small craft advisories appear to be on track and no modifications were necessary. Lingering steep waves from 5-7 ft and lingering N-NE gusts to 20 kt are on the fringes for an advisory Friday morning and an extensions did not seem necessary at this time. Overall lighter winds are expected for Friday except for perhaps localized afternoon gusts near 20 kt right along the land-ocean interface once the thermal trough shifts inland. Calmer conditions with much lower seas are anticipated for Saturday. NBM guidance continues to indicate low chances for even gust to 20kt late on Saturday as southerlies begin to develop and short period SW waves increase during the overnight hours. On Sunday NBM continues to indicate low chances (less than 25%) for wind gust to 25 kt or more. Deterministic models, including the NAM-nest, GFS, ECMWF and ICON continue to trend stronger with southerlies on Sunday. Edged wind forecast higher over NBM on Sunday into Monday. ECMWF, NAM12, GFS and ICON models indicate potential for gusts to 35kt. So stay tuned as the southerly winds in advance of the front may be much stronger. Also, steep southerly waves are forecast to build to 6 to 8 ft while a large long period westerly builds to 10 to 13 feet. There may be window for a sneaker wave threat Sunday morning into early afternoon before southerly winds and short period waves increase. Stay tuned as this longer period swell may pose a risk for sneaker waves on Sunday. A secondary trough may bring another increase in south-southwest winds by Monday, but confidence on the wind strength is low with NBM chances for gusts to 25 kt less than 20%. Seas do look to remain elevated and hazardous into Monday due to a combined westerly swell and steep SW wind waves fromt 10-12 ft. DB && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Frost Advisory from 2 AM to 9 AM PDT Friday for CAZ110-111- 113>115. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 PM PDT this evening for PZZ450- 455. Small Craft Advisory until 3 AM PDT Friday for PZZ470-475. && $$ 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

415 FXUS66 KMTR 032342 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 442 PM PDT Thu Apr 3 2025 ...New AVIATION, MARINE... .SYNOPSIS... Issued at 1225 PM PDT Thu Apr 3 2025 Warming and drying trend continues with temperatures above seasonal averages by Friday. A weak cold front interrupts the trend Sunday and Monday with light rain in the North Bay, before temperatures rise much above seasonal averages by the middle of next week. && .SHORT TERM... (This evening through Friday) Issued at 1225 PM PDT Thu Apr 3 2025 Skies are generally clear with some cumulus clouds developing over the ridgelines, with lingering cold air aloft supporting the potential for some isolated showers this afternoon and evening, although accumulations are not expected to rise above a few hundredths of an inch. Upper level ridging over the eastern pacific and western Canada contributes to a warming and drying trend, with high temperatures today rising to the lower to middle 60s inland, the lower to middle 60s on the Bayshore, the middle 50s to the lower 60s along the coasts, and the upper 40s to the middle 50s across the higher elevations. A light onshore breeze will develop later this afternoon, with light winds and generally clear skies overnight contributing to chilly temperatures on Friday morning, although with Friday morning`s lows in the upper 30s to the upper 40s across the lower elevations, the temperatures will not be cold enough to warrant a Frost Advisory. Temperatures continue to inch upwards on Friday, as the upper level ridge expands onshore and pushes an upper level trough into Arizona and northwestern Mexico. High temperatures reach the lower to middle 70s in the inland valleys, the middle to upper 60s along the Bayshore, and the upper 50s to lower 60s on the Pacific coast, warm enough to reach Minor HeatRisk along the Bayshore and in the northern Salinas Valley, meaning that there is a low risk for heat related illnesses among people extremely sensitive to heat, especially those without effective cooling and/or adequate hydration. && .LONG TERM... (Friday night through next Wednesday) Issued at 1225 PM PDT Thu Apr 3 2025 The warming and drying trend continues through the weekend with the upper level ridge building across the West Coast. This weekend, highs should reach the middle 70s to near 80 across the inland valleys, the upper 60s to the lower 70s in the Bayshore, and the lower to middle 60s along the Pacific Coast. For context, this is around 5 to 10 degrees above the seasonal average, and Minor HeatRisk continues across the inland valleys and close to the bays. On Sunday and Monday, a cold front will skirt the Bay Area, bringing an interruption to the warming trend and a chance for light rain, especially north of the Golden Gate, where rain totals of a quarter to a third of an inch are expected in the Sonoma coastal ranges, with up to a tenth of an inch across the rest of the North Bay. Rain chances decrease sharply south of the Golden Gate and once you`re in the Central Coast, rain chances are essentially nil. The current forecast also calls for temperatures to drop back to around or slightly below the seasonal average across the region. The warming trend resumes after the cold front moves out and a ridge builds over the western United States, with high temperatures in the warmest inland regions continuing to climb into the lower to middle 80s by mid-week. && .AVIATION... (00Z TAFS) Issued at 442 PM PDT Thu Apr 3 2025 Patchy cumulus clouds continue across the region with stratus expected to filter in along the coastline overnight (most likely to impact MRY, SNS, and HAF). Conditions will be slightly more moist than last night which may result in minimal visibility deductions across the North Bay. Moderate onshore winds will ease overnight before returning again during the day tomorrow. Vicinity of SFO...VFR through TAF period. Low chance for MVFR CIGs overnight with guidance keeping CIGs closer to coastline/away from SFO. Moderate west winds will ease overnight before redeveloping tomorrow during the day. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Patchy cumulus clouds are resulting in temporary broken conditions at MRY this afternoon through 02Z. Otherwise, VFR prevails through the early morning hours when stratus will start to move into the Monterey Bay Region. Higher confidence in MVFR CIGs at MRY and slightly lower confidence for MVFR CIGs at SNS. Moderate west to northwest winds will ease overnight before moderate northwest winds redevelop during the day tomorrow. && .MARINE... (Tonight through next Tuesday) Issued at 442 PM PDT Thu Apr 3 2025 High pressure over the Eastern Pacific will maintain moderate northerly winds over the coastal waters through the end of this week. Winds will be locally stronger over the outer waters and north of Point Reyes. These stronger winds will result in steeper wind waves and hazardous conditions. Winds and seas will diminish by Friday. A longer period swell will arrive late this weekend with increased shoaling near the coast, bays, and harbor entrances. && .BEACHES... Issued at 414 AM PDT Thu Apr 3 2025 As sensible weather conditions improve with warmer weather over the weekend and early next week beachgoer traffic may increase. As such, beachgoers should be mindful as a longer period swell arrives Sunday. This longer period will result in hazardous beach conditions with increased sneaker wave risk, rip current risk, and larger shore break. A Beach Hazard statement will likely be need as Sunday nears. Beachgoers should stay off of jetties and rocks, keep pets on a leash, wear a life jacket, and never turn your back on the ocean! && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory until 3 AM PDT Friday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm. && $$ SHORT TERM...DialH LONG TERM....DialH AVIATION...Kennedy MARINE...Behringer Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, X, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea

736 FXUS66 KOTX 032217 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 317 PM PDT Thu Apr 3 2025 .SYNOPSIS... The showers risk this evening decreases, leading into with a warming and drying trend Friday into the weekend. Early next week looks wet and cool again. && .DISCUSSION... This afternoon into tonight: Scattered showers will continue over the Idaho Panhandle and eastern third of Washington through the next few hours, decreasing in coverage and intensity heading past sunset. The axis of an upper trough will continue to shift southeast, with the northerly jet nosing across the region. This is interacting with the daytime heating and convective instability and lingering moisture to bring the aforementioned showers. These will be most numerous over the central and southern ID Panhandle and southeast WA along that axis. These will be in the for of rain or rain/snow mix, with the potential for some embedded graupel showers. T-storms may also be embedded with these showers, but they would be isolated and weak. The winds will be breezy from the north through early evening too, especially around the Okanogan Valley down into the western basin and near the Blues/Southeast WA/lower ID. Gusts of 15-30 mph will be possible. Heading into later this evening into the overnight, high pressure starts to build in with strong subsidence. This will lead to clearer skies and decreasing winds. There is some risk for patchy fog in the sheltered Idaho Panhandle valleys, but coverage looks low. The central and southern ID Panhandle through SE WA will need to be monitored most, as the precipitation moving through may be enough to moisten the BL to bring a bit more fog currently in the forecast. Low will be in the 20s to mid-30s. Friday to Sunday. Drier and warmer weather is forecast for much of the weekend. A high amplitude ridge of high pressure builds over the region into early Sunday. There is the off chance of a stray shower near the north ID mountains, near the Canadian border, Friday PM. Otherwise look for mostly clear to partly cloudy skies and light winds. Heading into Saturday and especially Sunday, clouds increase some ahead of an offshore low and with an incoming warm front. The PoPs remain low, until Sunday afternoon when the approach of that low will bring about 20-40% chance of showers near the Cascade crest. Temperatures will be near to slightly above normal Friday, then a more notable warm-up comes for Saturday and Sunday when highs will be about 10 degrees above normal. Look for upper 50s and 60s Saturday and more 60s and low 70s Sunday, with the exception of upper 50s and lower 60s near the Cascades. Low will remain in the 30s Saturday morning, with a few upper 20s in the sheltered mountain valleys, then the 30s to low 40s are expected Sunday morning. Sunday night to Thursday: The weather pattern turns a bit more active and cooler. Between Sunday night and Monday the next organized system moves inland, with an cold front/upper trough couplet. PWATS rise to around 180-210% of normal or 0.50-0.80 inches. Precipitation chances expands from west to east Sunday nigh into Monday morning, with the highest risk Monday before the potential start to wane from the west and the higher risk starts to retreat to the mountain zones Monday night. Some t-storms are possible Monday afternoon, with the best chances over NE WA and the ID Panhandle. They may be accompanied by brief heavy rains, small hail and gusty winds. Additional shortwaves move in heading into Tuesday to revitalize the precipitation potential. Winds in general will become gusty through Monday with the passing front and again Tuesday afternoon with the next disturbance. Afternoon gusts of 10-20 mph are forecast, locally up to 30 near the Blue Mountains and Okanogan Valley/Waterville Plateau. As for precipitation amounts, areas away from the lee of the Cascades and deeper Columbia Basin will see the most. The 24-hour probability of wetting rains (>=0.1") through Monday evening is around 70-100%, per the LREF ensemble forecast. It is only around 40-50% in the deeper basin. Then through Tuesday evening with the next wave that probability is around 30-50% in the lowlands, except near 10%-20% in the lee of the Cascades and deeper basin. In the mountains the potential is around 70-90%, highest near the Cascades. For most this will be in the form of rain. Between Sunday night and Tuesday night around 0.20 to 0.5" of precipitation is possible, with higher amounts in the mountains (potentially over an inch near the Cascade crest.) The NWRFC river forecasts do show some rises but nothing that goes high enough to cause an impacts. It won`t all be rain. Snow levels do drop to around 4-5.5kft Monday evening and to between 3.5-5.0kft for Tuesday, lowest near the Cascades. This means some snow potential around the passes. With that said, most areas are forecast to see less than a half inch except the Cascades which could see 1-3 inches. The best potential there will be Monday overnight and Tuesday morning, while the daylight hours accumulations should be less. For Wednesday and Thursday the area remains in a southwesterly flow, with a trough offshore and the ridge axis just to the east. Occasional impulses ride in and this will keep some shower chances alive around the mountains and also near the eastern third of WA/lower ID. Overall, however, precipitation amounts if any look lighter. It will remain a bit breezy, especially Wednesday, with gusts forecast to be around 10-20 mph. High temperatures will largely be in the 50s, with some 60s in the deeper basin and L-C Valley. Lows will be in the upper 30s and 40s Sunday night/Monday morning, then largely 30s and low 40s thereafter. /Solveig && .AVIATION... 00Z TAFS: An upper trough shifting east over the area will continue to mean some isolated -shrasn/-shra, a chance for isolated afternoon -tsra, and local MVFR conditions in heavier showers before 02Z. Wind will also be slightly gusty, near 20 kts or so in the afternoon. High pressure builds in from the west leading to drier weather and subsidence, leading to mainly VFR conditions. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate to high confidence in VFR condtions. Moderate confidence in MVFR conditions with heavier showers. Some risk for localized fog overnight/early Friday AM. Confidence is low. The main TAF sites that indicates some potential is near COE, PUW, LWS, but confidence is low with ensembles showing only a 5-10% chance at these location. ----------------------- Confidence descriptors: Low - Less than a 30 percent chance Moderate - 30 to 70 percent chance High - Greater than a 70 percent chance && .PRELIMINARY POINT TEMPS/POPS... Spokane 31 56 32 62 36 67 / 20 0 0 0 0 0 Coeur d`Alene 28 55 30 60 34 66 / 20 0 0 0 0 0 Pullman 29 54 31 59 37 66 / 20 0 0 0 0 0 Lewiston 34 59 35 65 40 71 / 20 0 0 0 0 0 Colville 27 57 30 61 34 65 / 0 0 0 0 0 0 Sandpoint 29 53 30 59 34 62 / 10 0 0 0 0 0 Kellogg 27 51 31 57 36 63 / 30 0 0 0 0 0 Moses Lake 31 62 34 65 39 69 / 0 0 0 0 0 0 Wenatchee 36 60 38 63 43 65 / 0 0 0 0 0 10 Omak 31 61 34 64 38 67 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$

768 FXUS66 KPDT 032349 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 449 PM PDT Thu Apr 3 2025 .Updated Aviation Discussion. .AVIATION...00Z TAFS...VFR conditions currently at all sites, which will stay the course through the period. Winds will stay light and below 10 kts through Friday afternoon, with the only exception being KDLS which will hover around 10 kts through the remainder of the evening. Ceilings will stay near 10kft overnight before lifting through Friday morning and afternoon. 75 && .PREV DISCUSSION... /issued 206 PM PDT Thu Apr 3 2025/ SHORT TERM...Tonight through Saturday...Water vapor satellite imagery this afternoon shows a broad upper trough gradually pushing east while upper level ridging builds offshore the PacNW. Visible satellite and radar imagery show light showers continuing south across the Blue Mountains this afternoon, with partly cloudy conditions across much of the area and mostly cloudy conditions across the eastern mountains. Through this evening, a shortwave slowly sliding down the backside of the broad upper trough will continue to bring rain/snow shower chances (20-40%) across the northern Blues and Wallowa county while the rest of the forecast area remains dry with locally breezy conditions. By tonight, the upper level trough and shortwave will push east of the region, allowing the upper level ridge offshore to begin pushing onshore. Dry conditions and a warming trend of 2-5 degrees between each day will develop with the upper ridge overhead through the weekend. Locally breezy to breezy conditions today will also give way to light winds and light afternoon gusts as the upper ridge continues to shift east. While conditions are expected to warm each day, clear skies and a lingering cold airmass will result in valley areas and portions of the Columbia Basin to dip to or just below freezing tonight. This will also result in a chance (25-40%) of frost developing across portions of central OR, north central OR, and portions of the Columbia Basin, dropping to 10% or less by Saturday morning as the warming trend takes hold. Lawhorn/82 LONG TERM...Sunday through Thursday... 1. Dry weather to begin the period 2. Upper level trough to bring precipitation to region with lingering mountain showers. 3. Temperatures to flux between above and near seasonable Models are in relatively firm agreement that an upper level ridge will situate itself over the region through Sunday afternoon. The upper level ridge will bring dry and warm conditions across the area with above seasonal average temperatures. By Sunday night, models show an upper level trough to begin pushing onshore bringing a surface cold front, cooler temperatures and high probabilities of widespread precipitation. Most notable variation in the clusters for the trough is the timing of the oncoming precipitation. Models show the trough to meander across the region and exiting Monday night. An upper level `dirty` ridge will then begin to build in over the region bringing drier conditions to the lower elevations with some high mountain showers. Much of the precipitation that will come with the upper level trough will be along the crests of the Cascades and along the eastern mountains and the Blues. 24 hour raw ensembles show the precipitation accumulation along the Cascades to be primarily rain except above 6500 ft. Raw ensembles show the 24 hr probability of precipitation of 0.50 inches to be 70-90% along the Cascade crests and 40-70% for the higher elevations of the eastern slopes. 30-60% probabilities for 0.05 inches along the Blue Mountains and the foothills and 50- 70% for central OR. Lastly, 10-20% probabilities of 0.01-0.03 inches for the Basin and the adjacent valleys. Lingering showers will continue over the Cascades, eastern mountains and the Blues with less than 15% probabilities of isolated thunderstorms embedded Monday and Tuesday. Temperatures will fluctuate through the longer term between above and at normal temperatures. The trough to start will bring warmer temperatures across the region with the EFI showing the higher than normal temperatures being along the eastern slopes of the Cascades. The difference from climatological normal ranges between 5-10 degrees. Temperatures will be more widespread above normal Sunday as the ridge settles over the region with 5-10 degrees above normal across the majority of the region. A surface cold front associated with the upper level trough will bring with it cooler temperatures Monday and the difference from climatological is roughly at or just slightly below normal. The next ridge will then bring temperatures back above normal again Tuesday through Thursday. With that said, NBM shows temperatures to be in the upper 60s to low 70s across central OR, the Gorge, Basin, foothills and mountain valleys Saturday and Sunday. Monday NBM shows temperatures to drop into the upper 50s to low 60s with isolated upper 60s in the Basin. Tuesday through Thursday will return to temperatures much like Saturday and Sunday. Confidence in the temperature is moderate/high (70-90%) with raw ensembles in agreement. 90 && .PRELIMINARY POINT TEMPS/POPS... PDT 33 60 34 67 / 0 0 0 0 ALW 36 60 36 65 / 0 0 0 0 PSC 34 65 33 69 / 0 0 0 0 YKM 34 63 35 66 / 0 0 0 0 HRI 34 64 33 69 / 0 0 0 0 ELN 32 60 34 64 / 0 0 0 0 RDM 28 60 28 69 / 0 0 0 0 LGD 30 57 29 62 / 0 0 0 0 GCD 27 57 30 63 / 10 0 0 0 DLS 37 66 38 70 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...82 LONG TERM....90 AVIATION...75

592 FXUS65 KREV 032015 AFDREV Area Forecast Discussion National Weather Service Reno NV 115 PM PDT Thu Apr 3 2025 .KEY MESSAGES... * Mostly dry with light winds and a gradual warming trend each day through Sunday. * Brush-by front brings mountain rain and snow showers along with areawide breezy winds on Monday. * Warming trend returns for the balance of next week, with widespread 70s and 80s in the valleys, 50s and 60s in the mountains. && .DISCUSSION... * Ridging works into the region starting tomorrow with dry conditions expected through Sunday. Warming each day, but especially on Sunday when winds kick up a little and turn more W/SW vs E/NE. * Isolated snow showers this afternoon and early evening over the high Sierra, per latest HREF guidance. Probability for measurable snowfall is low, under 20%. Clearing skies tonight should yield areas of freezing fog again in favored valleys, such as around Truckee. * Brush-by cold front brings showers mainly to mountain areas Tahoe northward late Sunday night into Monday morning. Rain-snow lines are high, 7000-8000` per latest NBM so travel impacts look minimal. 20% chance for 0.1" or more rainfall in mountains, 5% of W Nevada. For the rest of the area including the E Sierra along Hwy 395 and W Nevada, main change Monday will be cooler temps vs Sunday along with breezy winds. Gusts on the order of 30-40 MPH as the "best guess", with 20-40% odds of seeing anything over 45 MPH. * Balance of next week the warming returns. Wednesday-Thursday look to be the peak with widespread 70s and some 80s in W Nevada, with 50s and 60s for mountain communities. Could continue into Friday. 35-50% probability for RNO seeing 80+. Snowmelt flows on creeks and rivers will see some rises, but flooding not expected. * Majority of guidance does indicate a cooling pattern the following weekend (4/11-13) with increased breezes and chances for precip. Low confidence this far out with large spread in NBM guidance. It is spring after all... -Chris && .AVIATION... * Generally quiet weather for flying through much of the weekend, with VFR conditions and light N/NE/E winds, including for RNO. * Isolated (10-20% odds) snow showers over the high Sierra today could produce brief MVFR-IFR conditions with mountain obscuration. Unlikely (under 10%) to directly affect TRK, TVL, or MMH. * Freezing fog is likely for TRK again tonight with clear skies and residual moisture from the recent storm. Confidence is 80% for LIFR between 6z-18z/Fri. Can`t totally rule fog out for other Sierra valleys including around Mono Lake and TVL but odds are 20% or less. -Chris && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

101 FXUS66 KSTO 032002 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 102 PM PDT Thu Apr 3 2025 .Discussion... .Synopsis... Warm and mild weather expected through weekend`s end with light north winds at times. Early next week will see a weak system bring light precipitation to Northern California, mainly over the mountains and adjacent foothills. .Key Messages... * Drier and warmer weather returns through the weekend. * Chances for Valley Highs > 75 Degrees Saturday/Sunday: 50-90% * A weak system will bring clouds and light precipitation mainly to areas in northern Sacramento Valley Sunday night and Monday. * 24-Hour Mountains/Foothills Precip. Amounts > 0.25" (Sunday- Monday): 30-60% * Snow levels will be high, so light snow will be limited to highest peaks * Mild and dry conditions after Monday into middle of the week. .Changes from previous forecast... * No changes from previous forecast. && .AVIATION... Mainly VFR conditions across interior NorCal next 24 hours. Light mountain showers through 03z-06z Friday, mainly over the northern Sierra. Winds from the north less than 12 knots. Increased north to east winds after 15z Friday, with northerly wind gusts up to 15-20 kts in the Valley, and northeast/east wind gusts up to 20-25 kts over the mountains. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

902 FXUS65 KMSO 031857 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 1257 PM MDT Thu Apr 3 2025 .DISCUSSION... KEY MESSAGES: - A Canadian cold front is bringing snow to northwest Montana, including the Flathead valley through this afternoon - Temperatures will increase going into the weekend, peaking on Sunday - Low pressure moves into the Northern Rockies Monday PM - Tuesday AM Minor winter weather impacts are lingering in northwest Montana this afternoon behind a Canadian cold front that moved over the Continental Divide this morning. Snow will continue, moving southward as the afternoon unfolds. Expect rain turning to light snow this afternoon for west-central Montana including Missoula, the Bitterroot Valley, and possibly Butte. The main feature resulting in today`s winter weather, a Canadian low and an associated cold front, will move east tonight while high pressure builds in its wake. Clouds will decrease on Friday as temperatures begin to rise. Daytime highs will get into the 60s by Saturday in the valleys of western Montana, while the lower Salmon and Clearwater valleys flirt with 70. Sunday is still looking like the warmest day during this period of high pressure. Montana will start to see 70 degrees as the Bitterroot Valley has some upper 60s to low 70s in their forecast. Elsewhere in Montana, expect mid to upper 60s in the valleys. Meanwhile, in Idaho, the forecast shows upper 70s for the lower Salmon/Clearwater valleys. Low pressure will take back over by Monday night. Snow levels will remain at mountain pass level or above, and precipitation will be focused on Continental Divide in MT, and Clearwater and Idaho Counties in ID, especially in the higher terrain. A dusting of new snow on Lookout, Lolo, Lost Trail, and Marias Passes on Tuesday morning should not be a surprise to motorists. A cool, active pattern will persist through about Wednesday under moist southwest flow aloft. && .AVIATION...A cold front will continue to slide to the south and west during this afternoon and evening, potentially impacting KMSO and KBTM with decreasing visibility and ceiling with rain/snow showers. Gusty north or northeasterly winds will accompany precipitation. Clouds will decrease overnight tonight as high pressure builds for Friday. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...Winter Weather Advisory until 3 PM MDT this afternoon for Flathead/Mission Valleys...Kootenai/Cabinet Region...West Glacier Region. ID...None. && $$

503 FXUS65 KBOI 032037 AFDBOI Area Forecast Discussion National Weather Service Boise ID 237 PM MDT Thu Apr 3 2025 SHORT TERM...Today through Saturday night... Drying out today as the trough that has been bringing us our weather as of late exits the region. The greatest chance of precipitation comes this afternoon with a 20-30% chance over the Boise Mountains. This region also maintains a low chance of thunder (<10%) as instability builds overhead. Snow levels around 4000-4500 feet support snow/graupel being the dominant precipitation type, little accumulation is expected. Skies begin to clear tonight with overnight lows reaching 25-30 degrees in lower elevations. High pressure begins to set in over the region Friday as an upper level ridge moves in overhead. This supports a warming trend through the weekend with temperatures making it into the upper 50s to lower 60s Friday and Saturday. Breezy winds this afternoon into tonight in the Snake River Valley and near the Nevada border, generally decreasing through Saturday night. .LONG TERM...Sunday through Thursday...Warming continues into Sunday as the upper ridge axis shifts to the east. A sharp shortwave trough will swing into the area Sunday night increasing the chance for precipitation across SE Oregon, then spreading into SW Idaho early Monday. This system is connected to a narrow but deep moisture plume that will lift precipitable water values into the 90th percentile across the region Sun night/Mon. Snow levels will start off around 8kft MSL and remain above 6000-7500 feet through Monday, which keeps most sites as rain. Liquid totals of 0.25-0.50 inches are expected across the mtns of SE Oregon and SW Idaho from Sunday night through Monday night. Snowmelt from the mild temperatures over the weekend coupled with the expected precipitation will increase stream/river flow early next week. Showers linger across the e-central Oregon and w-central Idaho mtns through Tuesday as snow levels bottom out between 5-6kft MSL. Dry weather returns for Wed/Thur as an upper ridge rebuilds along the Continental Divide. Temperatures are 5-10 degrees above normal through the period. && .AVIATION...Mainly VFR. Scattered mtn showers and isolated thunderstorms producing MVFR and mtn obscuration through early evening. Scattered showers and isolated thunderstorms will develop this afternoon mostly over higher terrain. Showers/storms could produce outflow winds to 25 kt. Snow levels 3500-4500 ft MSL. Surface winds: W-NW 5-15 kt with gusts to 25 kt through 02Z. Winds aloft at 10kft: N-NE 10-20 kt. KBOI...VFR with NW winds through the night. Scattered showers this afternoon along Boise foothills will obscure mountains at times. Weekend Outlook...Scattered cumulus buildups Friday afternoon could obscure mtn tops, otherwise VFR through Sun under mostly clear skies. Surface winds: Generally less than 12 kt. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...None. OR...None. && $$ www.weather.gov/Boise Interact with us via social media: www.facebook.com/NWSBoise www.x.com/NWSBoise SHORT TERM...NRF LONG TERM....DG AVIATION.....DG

076 FXUS65 KLKN 031926 AFDLKN Area Forecast Discussion National Weather Service Elko NV 1226 PM PDT Thu Apr 3 2025 .SYNOPSIS...Upper-level troughing just to our east will slowly move into the central US into this weekend, with a few isolated snow showers this afternoon, mostly tapering off into Friday. High pressure will build across the West into the weekend bringing drier and milder conditions. A weak frontal system will bring a slight chance for showers and snow showers to northern portions of the state on Monday before high pressure builds back across the area into the middle of next week with much warmer conditions. && .SHORT TERM...Tonight through Friday night Scattered snow showers on radar once again across the region, quite similar to yesterday afternoon. A quick look at the upper- level pattern also shows little change, hence the continued weak instability and convective snow showers. The main trough axis has shifts to our east into Utah, leading to slightly less SB CAPE, thus snow showers will trend slightly weaker and more widely scattered through the balance of the day. Highs today continue below average in the low 40s. Snow showers are expected to taper off after sunset this evening, with clearing skies into the overnight. Any snowfall with these showers will quickly melt with afternoon highs well above freezing, but quick accumulations could lead to slushy roadways on I-80 at Pequop Summit and on NV 225 near Wildhorse Reservoir with a 40% chance for half an inch of snow or more through tonight. The trough pushes further east into the Rockies Friday, with mid- level height rises, thus expect slightly warmer highs and less afternoon convection clouds. Cannot rule out an isolated snow shower to two east of US-93 towards Ely closer to the departing upper-level trough, but chances are less than 10%. .LONG TERM...Saturday through Thursday A warming trend and dry weather pattern is expected throughout the forecast period, except for Monday, as an upper-level trough exits the state and high pressure moves in. On Monday, a shortwave trough will move through northern Nevada, bringing light showers and breezy winds to the region, but temperatures will remain warm. Afternoon highs are expected to reach the upper 60s and lower 70s by the beginning of next week, eventually warming to the upper 70s by midweek. Enhanced snowmelt due to the warm temperatures may cause water levels in some rivers to rise to action stage, increasing the potential for flooding in some areas around rivers. Record and near record highs are possible on Wednesday and Thursday, with a 50% chance of cities like Ely seeing their record highs breaking. && .AVIATION...Mostly VFR conditions through tonight across the area terminals with northerly winds 5 to 10 kt, with gusts to 20 kt at ELY and TPH. Scattered snow showers through 03Z, with brief a 10-15% chance for MVFR conditions in the strongest snow showers at KEKO, KELY, and KBAM. Winds ease tonight and resume a north- northeasterly flow tomorrow 5-10 kt. && .LKN Watches/Warnings/Advisories... None. && $$ 84/89/84