263 FXUS66 KSEW 101638 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 938 AM PDT Sun May 10 2026 .SYNOPSIS... A weak frontal system will clip the area today for increased cloud cover and cooler temperatures. Warming temperatures and high pressure return to the area early in the week, with Tuesday likely to be the warmest day. A transition to a cooler, more unsettled pattern is expected for the second half of the week. && .SHORT TERM /TODAY THROUGH TUESDAY/... No updates have been made this morning. Please see below for an update to the aviation section. High temperatures will cool several degrees and a few spots near the coast and across the North Interior might get a shower or two. High pressure aloft will begin to rebuild into the region tonight into Monday with the low level flow turning northerly. After a few morning clouds, Monday will feature mostly sunny skies, modestly warmer temperatures and breezy north winds through Puget Sound. Thermally induced low pressure at the surface expands northward along the coast early Tuesday with the low level flow turning weakly offshore. This will give us a good spike in temperatures with most of the area, including the coast, seeing highs in the 70s and lower (even a few mid) 80s. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... The forecast picture, particularly on Wednesday, takes a more difficult turn as we transition to low level onshore flow and a closed upper trough approaches somewhere near the Northern California coast. The ensembles have been having a tough time for several days resolving how this will ultimately play out. It potentially puts Western Washington in a region of southerly flow aloft along with some diffluence and associated elevated instability. Throw in some daytime heating and we have a recipe for potential thunderstorms. It must be stressed that this scenario is highly certain at this time, but the potential is there. Forecast high temperatures across the interior on Wednesday are quite uncertain...i.e. Ensembles for Seattle have a 15+ degree spread for Seattle`s high temperature. Thursday into next weekend, the ensembles are settling into general agreement that upper troughing over the Northeast Pacific will send a series of weak systems across the area for a few days of cooler temperatures and periodic chances of some light precip. 27 && .AVIATION... Southwest flow aloft will increase ahead of a trough/front moving across the terminals late tonight. There is a low 30% chance of a shower across the Puget Sound this afternoon, although conditions are largely dry through the TAF period. Ceilings remain elevated for most areas, especially in the interior. The only concern for lower ceilings this morning is the return of stratus to the coast early this morning (conditions likely to be as low as LIFR on the immediate coastline through the morning) and areas of stratus across parts of Puget Sound and fog over KPWT. Elevated stratus further inland remains intact through the afternoon, keeping probabilities of lower ceilings low this morning, and most likely VFR throughout the day. A push behind the trough Monday morning appears likely, with stratus making it inland into the interior. Winds variable this morning out of the southwest/northwest this morning, solidifying to northwest by early afternoon with sustained winds 5-10 kt (couple gusts to 20-25 kt in the Strait of Juan de Fuca areas this afternoon). KSEA...A brief spell of MVFR cigs is expected for the next couple of hours this morning. However, mostly VFR expected this afternoon and tonight , with high clouds beginning to scatter later in the afternoon. Lamp has a 30-50% chance of MVFR stratus returning to the terminal Monday morning (from roughly 10Z-17Z). Winds variable between southwest/northwest this morning around 5 kt, becoming north/northwest today 5-10 kt. Couple gusts to 20 kt possible in the afternoon. HPR/41 && .MARINE... A weak trough will move through the waters today, with a slight chance of a shower in the Puget Sound later in the afternoon. Behind the trough, an onshore push will likely bring gusty winds in the eastern two thirds of the Strait of Juan de Fuca this afternoon and evening. A small craft advisory was issued through tonight. Outside of this, winds remain relatively light and primarily out of the north through the week. A potential system midweek may bring another push through the strait. Additionally, while low stratus is expected off the coast next couple mornings, there is potential for some pockets of fog over the coastal waters (especially in areas where the wind is calmer). Seas will hold around 4-6 ft through the week (with a brief jump to 6-8 ft midweek). HPR && .HYDROLOGY... The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated during this time as needed. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory until 3 AM PDT Monday for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. && $$

749 FXUS66 KPQR 101101 AFDPQR Area Forecast Discussion National Weather Service Portland OR 401 AM PDT Sun May 10 2026 .SYNOPSIS...High pressure will maintain dry and warm conditions through early next week. A weak shortwave trough will bring increased cloud cover and slightly cooler temperatures tomorrow. Temperatures rebound on Monday and Tuesday as high pressure re- builds. Precipitation chances return on Wednesday as a trough approaches the West Coast. Another trough from the Gulf of Alaska will maintain precipitation chances and a trend toward cooler temperatures by the end of next week. && .DISCUSSION...Today through Saturday...Satellite imagery shows a weak shortwave trough slowly moving into the region today. This shortwave will slightly brush the Pacific Northwest and bringing mid to high level clouds across the CWA. While we will likely see no precipitation with this shortwave, we will get a brief reprieve from the warmer daytime highs thanks in part to widespread cloud cover an relatively cooler onshore flow. So, while we will remain dry, said cloud cover and onshore flow will drop daytime highs towards the upper 50s to mid 60s along the coast and in the Cascade. Interior valley locations are expected to see daytime highs in the upper 60s to mid 70s. Looking towards Monday and Tuesday, there has minimal changes in model ensemble guidance. Said guidance is showing a return of high pressure over the Pac NW, which will bring a return of clear skies, warm daytime highs for Monday and Tuesday. Temperatures return to the 70s to near 80s by Monday from the coast to the Cascades, with the warmest temperatures expected within the interior valleys. Looking at Tuesday, models are still showing this as the hottest day of the week. Current guidance is showing highs in the low to upper 70s along the coast, mid 70s to low 80s for the Cascades and low to upper 80s for the interior valleys. Looking towards the middle part of next week, 500 mb WPC clusters show at least some weak troughing or a weak low moving over the northwestern coast of CONUS shown via lowering 500 mb heights. This continues to support at least some cooling off, think highs in the 70s rather than the 80s, for the middle of the week and continuing through the end of the week. The next chances for precipitation return on Wednesday as the aforementioned trough approaches the West Coast. The majority, approx 70%, of ensemble members show this trough tracking south of our area, either toward the California/Oregon border or further south into California. As a result, chances for precipitation are currently 15-25% west of the Cascades and 25-40% across the Cascades. In addition, southerly flow from this pattern would bring increased instability and thus a 15-25% chance for thunderstorms for the Willamette Valley and across the Cascades. The other scenario depicted by 25% of ensemble members has the trough swinging directly through the Pacific Northwest; in this case, we would see increased moisture and chances for precipitation. Continuing to look at the WPC 500 mb clusters, show a more significant pattern change for Thursday and Friday. However, while the Grand Ensemble does favor more troughing over the Pac NW, approx 30% of ensemble members are favoring a ridge of high pressure returning to western CONUS. Overall, am maintaining the cooling trend for the latte part of the week, but as for precipitation chances and timing, that remains uncertain. /42 && .AVIATION...Southwest flow aloft with northerly flow at the surface will continue as upper level ridge slowly moves eastward as a weak shortwave trough moves across the airspace. Said shortwave trough will keep scattered to broken high clouds streaming across the region. Predominately VFR conditions expected for inland locations, while the coast will experience MVFR/IFR conditions as marine stratus remains anchored to the coast through the majority of the TAF period. There is around a 15-20% chance for LIFR conditions along the coast through 20Z Sunday as well as a 10-20% chance for a brief period of VFR along the coast from 21Z Sunday through 03Z Monday. For the Willamette Valley from KSLE southward, models are hinting at lower stratus along the Cascade foothills that may backbuild to KSLE and KEUG from 12Z-22Z Sunday. However, probs for MVFR remain around a 15-25%. Overall, expect MVFR to IFR conditions along the coast with predominately VFR conditions inland through the TAF period. Winds generally out of the north/northwest below 10 kt. KPDX AND APPROACHES...VFR with high clouds streaming across the area with light northwest winds increasing in the afternoon. /42 && .MARINE...North/northwest winds across all waters will continue through the majority of today as a weak trough quickly moves across all waters. Overall, expect winds of 6 to 10 kt with gusts up to 20 kt along the coast. The highest winds are expected in zones PZZ253 and PZZ273 with less than a 10% chance of isolated gusts up 25 kt. Seas 4 to 6 ft at 10 to 12 seconds. Monday, weak high pressure returns across all waters which will maintain northerly winds across all waters. As high pressure briefly builds, northerly winds will increase resulting in gusts up to 25 kt for zones PZZ252, PZZ272, PZZ253 and PZZ273. Thus, have issued a Small Craft Advisory for the zones starting Monday afternoon through at least Monday night. Seas will also build towards 5 to 7 ft on Monday in response to the increasing winds. Looking towards Tuesday through at least Thursday conditions return to a more benign pattern with north to west winds, with gusts below 20 kt and seas 5 to 7 ft. Towards, Friday a slightly more active pattern looks favorable as a low drops out of the Gulf of Alaska towards the region. /42 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory from 2 PM to 11 PM PDT Monday for PZZ252- 253-272-273. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

433 FXUS66 KMFR 101032 AFDMFR Area Forecast Discussion National Weather Service Medford OR 332 AM PDT Sun May 10 2026 .DISCUSSION... Key Points: * After a slight cooldown Sunday, another warmup arrives early next week * Dry/breezy conditions this afternoon-evening (West of Cascades: NW/N), East of Cascades: W) * Above normal temperatures continue through the forecast (70s/80s) * Next chance for precipitation: Later Tuesday/Wednesday, some model disagreement Satellite shows marine stratus across Coos and Curry counties, including the Coquille Valley. The stratus is starting to expand to the Umpqua Basin, and these low clouds will burn off later this morning. The ridge will move eastward today while a dry front arrives. East side temperatures will be slightly warmer than Saturday temperatures while west side drops 5-10 degrees. RHs east of the Cascades will drop to the teens and low 20s in the afternoon with W/NW winds peaking around 12-17 mph. The coast will also see stronger winds near 10-15 mph this afternoon. Ridging will build again Monday, help warm temperatures to more than what was seen Saturday. Highs are forecast to near 90 degrees in the Rogue valley, mid-upper 70s for the coast, and low/mid-80s east of the Cascades! Monday winds are forecast to have a typical afternoon peak, and minimum RH values will be in the 15-25% range east of the Cascades and near 20-30% for portions of the Rogue Valley. Tuesday and beyond: An approaching cutoff low will influence midweek conditions, but with some uncertainty in the details. The first effects may be on Tuesday afternoon and evening, when southerly flow around the cutoff could bring gusty winds into the Shasta Valley, the southern Rogue Valley, and over the east side. These winds may reach Advisory speeds in the Shasta Valley (50-60% chances), but are unlikely to do so in other areas (10-20% chances over terrain in Modoc and southern Lake/Klamath counties). Uncertainty in the timing and position of the low is affecting confidence in other areas. ECMWF deterministic imagery brings the cutoff over the CWA on Wednesday morning, which limits daytime heating and makes thunderstorms less likely while rain showers are more likely. GFS imagery moves the cutoff farther south and arrives later on Wednesday, which is more favorable for afternoon/evening thunderstorms. Forecast daytime highs also reflect this uncertainty. NBM probabilistic guidance has an interquartile range (equal 25% chances) of Medford`s high being between 75 and 92 degrees. Beyond the cutoff, there`s good model agreement in a cooling trend from Thursday through Saturday. By Saturday, daytime highs may dip just below seasonal norms. -TAD && .AVIATION...10/12Z TAFs...A mix of IFR/LIFR conditions will persist this morning at the coast, Coquille Valley, and Umpqua Basin before improving again during the afternoon. Farther inland, VFR prevails with some high clouds drifting by at times. Guidance also some slight potential (10% chance) for lower clouds to filter into the Rogue Valley around sunrise, but conditions should remain VFR at the Medford terminal. Otherwise, VFR conditions can be expected through this evening, with gusty winds developing across the region in the afternoon/evening. && .MARINE...Updated 300 AM PDT Sunday, May 10, 2026...A thermal trough develops today, bringing increasing north winds and wind driven steep seas south of Cape Blanco through Monday. Gusty north winds and steep seas are expected to expand north of Cape Blanco on Monday before subsiding again late Monday night into Tuesday. -Spilde && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory from 8 AM this morning to 11 PM PDT Monday for PZZ350-356-370-376. && $$

988 FXUS66 KEKA 100720 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1220 AM PDT Sun May 10 2026 .SYNOPSIS...Temperatures will slowly continue to warm and are expected to peak on Monday. Gloomy stratus will continue to blanket the coast again Sunday with a better chance for clearing Monday. There is the possibility of some rain, drizzle, and inland thunderstorms on Wednesday or Thursday. && .KEY MESSAGES... -High interior temperatures will peak Sunday and Monday with moderate HeatRisk in Mendocino and Lake Counties. -Gloomy coastal skies will continue with potential scattering out on Monday. -Cooler temperatures and slight thunderstorm and coastal drizzle potential around Wednesday or Thursday. .DISCUSSION...The axis of the upper level ridges remains to the east of the area. The winds are keeping the marine layer clouds in place along the coast. Inland areas remain warm with highs in the 80s to near 90. The marine layer is keeping the western half of the coastal counties cooler. This slightly moderated air is impacting Gasquet, Hoopa, Garberville, Laytonville, Willits and down into Ukiah. These areas remained in the mid 70s to mid 80s today. Areas farther inland such as Weaverville, Covelo, and much of Lake county were in the upper 80s to around 90. Sunday is expected to be very similar to Saturday with a weak trough approaching from the west. The marine layer may slightly farther inland keeping temperatures slightly cooler than today. Sunday afternoon the trough moves through the area. This may increase the mixing and could bring some brief clearing at the coast. This shifts the wind to more offshore by Monday morning. There are better chances of more clearing by Monday afternoon. This offshore flow should also help bring warmer temperatures the the near coastal areas 10 to 20 miles inland with many of these areas reaching into the upper 80s to low 90s. Farther inland mid 90s are expected. There is the potential that the low clouds will linger at the immediate coast and keep temperatures around 60. This will likely be the warmest day of the next week for much of the area. Heat risk is expected to moderate in portions of Lake and Trinity counties. Tuesday an upper level low starts to approach the area and this is where model solutions start to diverge. Some of the ensemble clusters bring this low quickly north and into Washington and Oregon while the slowest solution keeps the low well off the California coast. The evolution of this low into Wednesday and Thursday will have big impacts on the forecast. This could bring the chance for Thunderstorms if the low moves onshore in northern CA. However some of the other solutions could keep hot temperatures over the area. Late in the week the models are showing zonal flow developing over the west coast. There are still some big differences whether there will be some weak ridging and dry weather or the remnants of the upper level low continuing to move through the area. Overall confidence is below normal in the extended period. && .AVIATION...Widespread stratus is bringing IFR conditions with local LIFR conditions this morning. These are expected to persist into at least early afternoon. This afternoon northwest winds start to increase and this may help to clear skies for a few hours. At ACV the HREF is still showing a 25 percent chance of MVFR CIGS lingering through the afternoon. CEC is seeing a better chance of clearing and remaining clear into the evening. At KACV there is a better chance of MVFR or IFR CIGS returning in the evening. MKK && .MARINE...Northerly winds are expected to increase through Sunday afternoon as an upper level trough moves out of the area. This appears to have slowed slightly, so have pushed back the start of the small craft advisory in the northern waters. Later this afternoon and evening winds are expected to be mainly around 20 to 25 KT with locally stronger areas in the lee of Cape Mendocino. The swell continues to move through the waters at around 3 to 4 feet at 12 to 14 seconds. Wind driven short period waves are expected to increase to around 5 to 9 feet Monday night. Monday the northerly winds are expected to diminish as an upper level low starts to approach the area. Lighter winds are expected on Tuesday and Wednesday. However there is quite a bit of uncertainty in the pattern for the middle of the week so confidence is a low and many different model solutions are possible. The middle of next week there is the potential for the northwest swell to increase some as well. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 3 AM PDT Monday for PZZ455. Small Craft Advisory from 1 PM Sunday to 9 PM PDT Monday for PZZ470. Small Craft Advisory until 9 PM PDT Monday for PZZ475. && $$ NOTE: The full forecast discussion is now regularly issued between 10 am/pm and 1 pm/am. Additional updates will be issued as needed. 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

215 FXUS66 KMTR 101557 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 857 AM PDT Sun May 10 2026 ...New UPDATE, MARINE... .KEY MESSAGES... Updated at 1205 AM PDT Sun May 10 2026 - Warming and drying trend will continue through early in the week with afternoon temperatures peaking on Monday - Moderate risk for heat-related illnesses for sensitive populations across the interior on Monday - Gradual cooling trend and potential unsettled weather from midweek through late week && .UPDATE... Issued at 855 AM PDT Sun May 10 2026 A deeper marine layer than anticipated (around 1500 ft in the North Bay and 2000 ft in the Bay Area and Central Coast) early this morning has resulted in a further inland extent of stratus. Thus, have lowered temperatures as mentioned in the short term discussion below, generally 3-5 degrees F cooler. Still expecting low clouds to retreat to the coast between 10 AM and 2 PM which will give way to mostly sunny conditions across inland areas. RGass && .SHORT TERM... Issued at 1215 AM PDT Sun May 10 2026 (Today through Monday) Let`s step back and take a look at the interesting longwave pattern over the CONUS - ridge of high pressure covers CA which is bookended by deep troughs on either side with one near the Great Lakes and the other near Gulf of AK. The pattern will hold in the near term, but will shift with a pattern change on the horizon, literally. So what does this set up mean for the Bay Area? A ridge of high pressure in May usually brings dry and mild conditions and Sunday is no exception. However, it`s the details that matter. Overnight satellite imagery shows solid stratus along the coast working its way inland. The marine layer will likely top out 900-1200 feet this morning and will be the spoiler for Max T potential. Would not be surprised one bit if the marine layer was able to squeeze out some drizzle along the coast. Model guidance has struggled the last few days regarding Max T and the marine layer influence...simply put the forecast was too warm. As such, trended temperatures downward from the NBM over inland valleys or areas that have a pronounced marine layer influence this afternoon. Went colder by 3-5 degs, but worried it wasn`t under cut enough. That being said, do expect the marine layer clouds to erode back to the coast by this afternoon with inland sunshine and coastal clouds. Regardless, if you have outdoor activities to celebrate Mother`s Day it will be pleasant with inland highs in the 70s and 80s and cooler at the coast in the 60s - bring a jacket. Could also be a tad breezy this afternoon with the temp difference from the coast to interior. Sfc pressure gradients remain onshore again, but are forecast to be weaker than Saturday where they peaked at 4.2 mb. Sunday night through Monday - the center of the upper ridge begins to shift toward the Desert SW while the upstream trough deepens and inches toward the West Coast. Despite the shift, Monday is still on track to be the warmest day of the forecast. 850 mb temps peak at 20-22C. Mixing those temps to the surface under ideal conditions would bring toasty temps. However, we still have some onshore flow and lingering marine layer. As such, max temps will be tempered near the coast and bays, 60s to lower 80s. Far interior locations will be in the 90s leading to some Moderate HeatRisk. && .LONG TERM... Issued at 1220 AM PDT Sun May 10 2026 (Monday night through next Saturday) The change in the longwave pattern begins to unfold Monday night into Tuesday. The upper level ridge is being replaced by a robust and anomalously deep upper low for mid May. Temperatures begin to drop in response to lower 500 mb heights and cooler 850 mb temps, but still above normal. By Wednesday near normal temperatures return thanks to the cut-off low over the region. Confidence fades on the details of the exact placement of the cut-off low...cluster analysis is split with some favoring more zonal flow and others farther south with a deeper low. Regardless of exact placement, it`s clear that temps drop and at least some drizzle is likely. A few members even show light showers Wednesday afternoon/evening (tstorms to the N). Zonal flow returns for the second half of the work week leading to rebounding temperatures and drier conditions. && .AVIATION... (12Z TAFS) Issued at 509 AM PDT Sun May 10 2026 Nearly ideal conditions exist for marine stratus /MVFR-IFR/ with satellite showing fairly widespread coverage across the Bay Area and north Central Coast. Despite that there`s a strong 500 mb ridge and warmth aloft (00z Saturday evening Oakland upper air sounding mandatory levels aloft were near 90th percentile for mid May), the marine layer is well defined with an inland intrusion supported by a 2.8 SFO-SAC pressure gradient. Travis AFB has had onshore gusts to 30 knots overnight for example. The marine layer varies in depth from 1200 feet to 2000 feet. 24 hour trends show steady to slightly higher surface dew point temperatures i.e. steady to greater amount of water vapor trapped beneath the marine temperature inversion. In the dry air above the marine layer temperature inversion, nocturnal radiative cooling like previous early mornings is good; forecast soundings show a similar vertical distribution of low water vapor/dry aloft tonight and Monday morning supportive of cooling again tonight and Monday morning. Run after run of the HRRR overnight continues to show stratus clouds beginning to mix out prior to sunrise, which is highly unlikely to happen this early. The NAM shows stratus lingering until late morning which seems more reasonable. The ACV-SFO pressure gradient is currently 3.7 mb and is forecast to increase later today to the evening before decreasing overnight, but there`s disagreement as to the strength of this gradient for today. Overall, it`s a challenging forecast not only for the public side and temperatures, but also for aviation side and ceilings forecasts. There`s been a steady application of northwest winds over the coastal waters, producing some cold water upwelling with sea surface temps near to 3F or 4F above May normals. It`ll take the higher sun angle of May to break through the stratus layer via vertical mixing today. Clearing times are mainly by late morning, though it may take an hour or two longer than that depending how well the stratus holds together through morning. For tonight and Monday morning, expect stratus including patchy fog to develop with MVFR-IFR-LIFR late tonight and Monday morning. Vicinity of SFO...Stratus /IFR/ intrusion is well established this morning per satellite and surface observations. Near 100% IFR probability on HREF at least early this morning, may also correspond to patchy light drizzle (from KHAF to KSFO to KOAK). For the time being, 12z SFO TAF is for dry runways. Stratus IFR ceiling increasing to MVFR by late morning with mix out by 20z today. Stratus /IFR/ returns 07z tonight with stratus prevailing through much of Monday morning. West wind 10 knots with a few gusts to 20 knots still possible this morning, otherwise increasing west wind 15 to 25 knots from late morning through the afternoon to early evening. West wind near 10 knots tonight and Monday morning. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...Stratus /IFR/ covers the Monterey Peninsula with stratus extending far into the Salinas Valley; the marine layer is ~ 2000 feet deep here in this part of the forecast area. A few patches of light drizzle are possible during the morning. Stratus /IFR/ conditions gradually improving to MVFR by late morning or early afternoon. Stratus /IFR/ returns tonight and Monday morning. West to northwest winds 5 to 15 knots. && .MARINE... (Today through Friday) Issued at 855 AM PDT Sun May 10 2026 Moderate seas and a fresh to strong northwest breeze with occasional near gale force gusts will continue through tonight. Locally gusty conditions are likely across the San Pablo and San Francisco Bays where terrain promotes wind funneling. Winds gradually ease starting late tonight across the inner waters then across the outer waters tomorrow becoming a moderate northwest breeze. Winds increase and seas build mid to late week. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this evening for Mry Bay. Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt Reyes 0-10 nm. Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm- Pt Reyes to Pigeon Pt 0-10 nm. Small Craft Advisory until 3 PM PDT Monday for Pt Arena to Pt Reyes 10-60 NM. Small Craft Advisory until 9 AM PDT Monday for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...MM LONG TERM....MM AVIATION...Canepa MARINE...Kennedy 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

663 FXUS66 KOTX 101201 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 501 AM PDT Sun May 10 2026 .KEY MESSAGES... - Breezy to locally gusty winds Sunday afternoon. - Widespread minor HeatRisk through Tuesday. This level of heat primarily affects those who are sensitive to heat. - Cold water temperatures pose a high risk for cold water shock and hypothermia for anyone who unexpectedly falls in. Wear a life jacket if recreating on or near the water. && .SYNOPSIS... A prolonged period of above normal temperatures will continue through Tuesday. Tuesday will be very warm with mid to upper 80s. Conditions will be mostly dry in the lowlands. Winds will be gusty Sunday, especially in Central Washington. && .DISCUSSION... Today through Tuesday: A dry cold front will move through the region today, bringing breezy westerly winds to central WA in the late afternoon. Winds will be from the northwest with sustained speeds around 15-30 mph with gusts up to 40 mph. Afternoon relative humdities will drop to the 20s bringing an elevated risk for grass fires. There may be some patchy blowing dust impacts as well. Winds will be lighter elsewhere. There is high confidence for high pressure to build in behind the front which will bring a warming trend into the 80s to low 90s Tuesday. Wednesday through Sunday: Incredibly, models are still split on how much precipitation and how warm the INW gets Wednesday as a trough off the CA coast moves inland. The NBM 25-75th spread for high temperatures is 17 degrees at Spokane AP with the 25th percentile at 70 degrees and the 75th percentile at 87 degrees. The spread for QPF remains significant as well with the 10th percentile bring dry at Spokane AP and the 90th having just over a tenth. I am thinking a middle end solution of temperatures in the 70s to low 80s with high cloud cover and mountain showers. There is a solid fetch of moisture with origins around the southern tip of Baja California and the northern California coast. The factor lacking for widespread steady rains will be the lack of forcing. The best dynamics on the latest global suite will be displaced to the south as models have trended south with the low. There will be a small chance of thunderstorms in the mountains Wednesday, but I am skeptical of the coverage of convection if we have a lack of forcing and cloud cover to overcome. There is still generally good agreement that unsettled and cooler conditions around normal will establish behind this system. Will have to monitor several days for breezy winds and some light precipition in the mountains (Wed-Sat). DB && .AVIATION... 12Z TAFS: VFR conditions under periods of upper-level cloudiness will prevail through the period. Locally breezy winds to develop after 21Z especially across central WA as a dry cold front crosses the Cascades. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence for VFR conditions for all TAF sites. There a slim chance for showers near the Cascades and Canadian border, this afternoon and evening, but the risk is low. ----------------------- Confidence descriptors: Low - Less than a 30 percent chance Moderate - 30 to 70 percent chance High - Greater than a 70 percent chance For additional probabilistic information for NWS Spokane airports, please refer to the Aviation Dashboard on our webpage: https:/www.weather.gov/otx/avndashboard && .Preliminary Point Temps/PoPs... Spokane 77 47 75 46 85 53 / 0 0 0 0 0 0 Coeur d`Alene 76 46 72 45 84 54 / 0 0 0 0 0 0 Pullman 75 45 70 44 84 52 / 0 0 0 0 0 0 Lewiston 81 49 76 48 88 56 / 0 0 0 0 0 0 Colville 78 42 79 43 87 50 / 0 0 0 0 0 0 Sandpoint 74 45 74 46 83 51 / 0 0 0 0 0 0 Kellogg 80 46 73 45 88 52 / 0 10 0 0 0 0 Moses Lake 81 46 79 48 90 54 / 0 0 0 0 0 10 Wenatchee 79 51 79 53 87 59 / 0 0 0 0 0 10 Omak 80 46 80 49 89 56 / 0 0 0 0 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

866 FXUS66 KPDT 101021 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 321 AM PDT Sun May 10 2026 .KEY MESSAGES... 1. Dry and warm conditions will persist through the week with near record temperatures possible 2. Breezy to windy through the gaps today 3. Midweek pattern shift will bring chances mountain showers and thunderstorms && .DISCUSSION... Current satellite shows some upper level clouds lingering over the area with a few isolated pockets of mid level clouds over the Kittitas Valley. CLouds are clearing out of central OR leaving them with mostly clear skies. This will assist with keeping overnight temperatures a bit warmer in the mid to upper 40s (70-90% confidence). Models show the upper level ridge to still be overhead keeping the area under warm and dry conditions. Temperatures will be 10-15 degrees above seasonal normal increasing to nearly 20-25 degrees above normal by Tuesday. Highs Sunday and Monday will be in the upper 70s to low 80s with 80-90% of the NBM raw ensembles in agreement. Tuesday however, ECMWF. GEFS and NBM ensembles all show temperature to be nearing the 90s with 80-90% probabilities. Looking at in house data, the mean max temperatures for Pendleton is 70 degrees, Tri- Cities is 76 degrees, Walla Walla is 71 degrees. These temperatures are well below the expected temperatures the ensembles are suggesting and could possibly break a few temperature records. Models shoe an upper level shortwave will make its way across the forecast area today showing another day of breezy to windy conditions through the mountain gaps. 70-80% of the NBM raw ensembles show Kittitas Valley and the Gorge seeing sustained winds between 20-30 mph with gusts of 40-45 mph today starting after 2 PM and persisting through 9 PM. After the front passes, winds will turn to typical diurnal winds under the ridge. Tuesday night models show an upper level system beginning to make its way into the region. Clusters show the variance between the models to be the timing and positioning of this system. Some models want to bring the system into the PacNW as a trough, some want to bring it a bit farther south of the region while others want to bring it under the region. Regardless of the scenario, each one leads to the breakdown of the ridge which will in turn lead to southwest flow aloft ushering in unstable conditions to the region allowing for the chances of thunderstorms. Looking at the NBM 12 hour probability of thunder, there is a 20-30% probability of thunderstorms forming over the OR Cascades as well as over the eastern mountains by Wednesday. Not only are there chances of thunderstorms, but there is also a 20-40% of mountain showers as well. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... VFR conditions will persist through the forecast period. Breezy conditions will occur across all TAF sites after 18-21Z with sustained winds of 10-20 kts with gusts 20-25 kts and persisting through 04Z. CIGs will be primarily 25 kft with no VIS issues. && .FIRE WEATHER... High pressure will persist through midweek with dry and warming conditions. A shortwave today will bring breezy west to northwest winds today, with strongest winds through the mountain gap areas of the Kittitas Valley and the Gorge. A breakdown in the ridge Tuesday will result in an increasing instability through central Oregon and the eastern mountains where 20-30% probabilities of thunderstorms may occur by Wednesday. This afternoons RHs will be mostly in the teens to mid 20s, with single digits in central Oregon with these RHs returning Tuesday afternoon. && .Preliminary Point Temps/PoPs... PDT 78 46 76 48 / 0 0 0 0 ALW 79 50 77 51 / 0 0 0 0 PSC 84 50 81 51 / 0 0 0 0 YKM 82 47 80 50 / 0 0 0 0 HRI 81 48 79 49 / 0 0 0 0 ELN 74 44 75 46 / 0 0 0 0 RDM 80 38 82 46 / 0 0 0 0 LGD 83 43 78 45 / 0 10 0 0 GCD 89 42 84 47 / 0 0 0 0 DLS 76 48 82 53 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...90 AVIATION...90 FIRE WEATHER...90

590 FXUS65 KREV 100906 AFDREV Area Forecast Discussion National Weather Service Reno NV 206 AM PDT Sun May 10 2026 .KEY MESSAGES... * A warming trend continues with near record high temperatures most likely today through Tuesday. * Dry conditions are expected through the beginning of the week with typical afternoon west breezes most days. * Some cooling returns by mid-late next week with isolated shower chances and periods of breezy winds. && .DISCUSSION... The latest forecast guidance continues to show an upper ridge over the W CONUS today and into tomorrow. A shortwave trough is seen moving through the PacNW this afternoon and evening though keeping the general ridging pattern intact over the CWA. The upper ridge then will restrengthen Monday and Tuesday with a closed low traveling through the Pacific behind the ridge. With this pattern aloft, the current warming trend will continue through Tuesday. As a result, near record to record daytime high temperatures across the region are expected through Tuesday with temperatures climbing to around 15-20 degrees above seasonal normals (please see the Climate section for a list of the current temperature records at our two climate sites: Reno, NV and South Lake Tahoe, CA). Generally, the temperature forecast for the next three days shows highs in the upper 80s to middle 90s range in NE CA and W NV valleys while the Sierra communities will range between the upper 70s and the lower 80s. The latest NWS HeatRisk forecast continues to display an areawide minor category of HeatRisk early next week with the warmer valley portions of W NV being in the moderate category through Tuesday. Please remember to stay hydrated and limit exposure to the sun during the warmest parts of the day especially if you have outdoor plans and are sensitive to heat. Also, please use extra caution near rivers and resist the urge to enter them to cool off as area rivers still remain cold and could be flowing fast, presenting a risk of hypothermia. The ridge pattern will also allow for generally dry conditions to prevail for the first half of this week. However, increased daytime heating could allow for brief pop-up showers though chances look to be less than 10%. The latest runs of a few of the CAMs show some isolated showers possible in Mineral County during the late afternoon and early evening hours today and tomorrow. It is also worth noting that the 00Z run of the RRFS is predicting some PM showers developing along the CA/NV border on Tuesday and moving north through the Tahoe area as well as Reno and Carson City. This model could be overdoing Tuesday afternoon convection, but will be monitoring this in case more models begin to agree. Afternoon winds are expected to be typical zephyr-type west-southwest breezes (gusts up to around 25 mph) through Tuesday. The upper air pattern looks to change by Wednesday as the resident ridge moves east with the aforementioned low making landfall on the west coast. There is still is some uncertainty in the evolution of this low through the rest of the week as ensembles forecast the low opening up into a trough as it makes landfall while the deterministic models continue it as a closed low as it moves through the CWA. But overall, this pattern will cause temperatures to begin a slow cooling trend while staying above seasonal normals going through the latter half of the week. Precipitation chances return to the region on Wednesday onward, but there is low confidence in details at this time due to the model uncertainty. Timing on this system is also still quite uncertain as the ECMWF shows an increased potential for showers and thunderstorms on Wednesday while the GFS delays this until Thursday. Will be monitoring this later week system for better agreement in future model runs. -078 && .AVIATION... VFR conditions are expected at most TAF sites today and tonight. KTRK looks to be the exception as there is a ~20% chance for patchy shallow fog developing between 10/10-15Z, which could cause sub-VFR conditions. Afternoon winds at area terminals will be out of the southwest to west with gusts up to around 20-25 kts mainly between 10/20Z-11/04Z. While dry conditions prevail, the warmer temperatures through Tuesday could potentially bring density altitude concerns each afternoon, especially for the western NV terminals. -078 && .CLIMATE... Current record high temperatures for Reno, NV that have potential to be broken or tied (Today-Tuesday): May 10: 88 F, set in 1934. May 11: 90 F, set in 2001 and 2013. May 12: 89 F, set in 1959 and 2013. Current record high temperatures for South Lake Tahoe, CA that have potential to be broken or tied (Today-Tuesday): May 10: 75 F, set in 2025. May 11: 78 F, set in 2013. May 12: 79 F, set in 1988 and 1996. && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

558 FXUS66 KSTO 091941 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1241 PM PDT Sat May 9 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Increasingly hot and dry conditions through early next week, with widespread Moderate HeatRisk Monday and Tuesday. - Hottest Days Monday and Tuesday with triple digit temperatures and daily record highs possible. - Slight cooling trend from Wednesday onward, with increased Delta breeze influence. && .DISCUSSION... ...Today through Friday... A warming and drying trend continues today as ridging build eastward. Widespread Minor HeatRisk is expected today and Sunday, with areas of Moderate HeatRisk in the Valley. High temperatures today are forecast to be in the high 80s to mid 90s. Lingering troughing influence will somewhat temper daytime highs and provide overnight relief through Sunday. On Monday and Tuesday, daytime temperatures will climb again, with widespread Moderate HeatRisk in the Valley both days. Valley highs have potential to both meet or exceed local records, as well as reach triple digits in some locations. The NBM has a 30 to 50% chance of 100 degrees or more in the northern San Joaquin Valley, as well as in the central Sacramento Valley (particularly in eastern Glenn and Colusa Counties, and Butte County). A Heat Advisory remains in place for these areas from 11am on Monday through 8pm on Tuesday. Areas closer to the Delta will see much better overnight relief on Monday and Tuesday, though daytime temperatures will still be quite hot. Be sure to practice heat safety! Drink plenty of fluids, stay in an air-conditioned room or in the shade during the heat of the day, and consider checking in on those more susceptible to heat. Ensembles depict the ridge breaking down towards the middle of next week which will result in a gradual cooling trend from Wednesday onward, however temperatures will still be 5 to 15 degrees above normal through the end of next week. && .AVIATION... General VFR conditions are expected over the next 24 hours. Surface winds generally 12 kts or less except near the Delta, where winds to 15 kts and gusts to 20-25 kts are possible. Local gusts up to 20 kts across portions of the southern Sacramento and northern San Joaquin valleys until 06z Sunday. && .STO WATCHES/WARNINGS/ADVISORIES... Heat Advisory from 11 AM Monday to 8 PM PDT Tuesday for Butte County Below 1000 ft-C. Stanislaus County including Modesto- Eastern Colusa County-Eastern Glenn County-W. Stanislaus County Above 1000 ft & I-5. && $$

884 FXUS65 KMSO 101016 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 416 AM MDT Sun May 10 2026 .DISCUSSION... KEY MESSAGES: - Summer-like warmth begins today: Unseasonably hot temperatures with widespread highs in the 80s today and low 90s in the lower elevations of Idaho.This near-record warmth will persist through mid-week. - Spring Thunderstorms Wednesday and Thursday: Mean hazards will be lightning and erratic outflow winds. - Weekend Cool Down, but near seasonable levels. The short-term is dominated by an upper-level ridge that will bring an immediate taste of summer to the Northern Rockies. A weak, moisture-starved shortwave will track near the Canadian border tonight which will bring passing mid to high-level clouds and breezy conditions through Monday. It will slightly temper the near-record warmth for Monday across much of the region. The notable exception will be further south, such as in the Salmon area, where temperatures are expected to remain quite warm in the mid-80s. The ridge re-amplifies on Tuesday, setting the stage for peak heating lasting into Wednesday. There is a 50% chance that some of the lower valleys of western Montana could hit 90 degrees. By Wednesday afternoon and Thursday, the ridge axis shifts eastward, introducing southwest flow and increasing instability. This will set the stage for spring thunderstorms with lightning and gusty outflows the main threats. Looking out to the late week pattern, forecast models are pointing to a much larger pattern change, through there remains considerable uncertainty regarding its exact evolution. The latest ensemble cluster analysis depicts a split between solutions...on one end of the spectrum they keep the warmer pattern going longer while on the other end, they bring a much cooler/wetter trough over the region. && .AVIATION...VFR flying conditions will continue across the Northern Rockies over the next several days. An upper level wave will bring a fair amount of middle to high clouds through Sunday night. This system will also bring a slight increase to the afternoon winds both today and Monday. Unseasonably hot afternoon temperatures in the 80s to near 90 will result in high density altitudes across the lower elevations of Idaho and western Montana through mid-week. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

404 FXUS65 KBOI 101227 AFDBOI Area Forecast Discussion National Weather Service Boise ID 627 AM MDT Sun May 10 2026 .UPDATE...Updated aviation discussion. && .KEY MESSAGES... - About ten degrees hotter Sunday, with lower elevations reaching 90 degrees for the first time this year. - Record high temps on Tuesday with temperatures in the mid to upper 90s in the lower valleys. - Cooler Wednesday with a chance of showers and thunderstorms. && .SHORT TERM /Through Tuesday Night/... Issued 232 AM MDT SUN MAY 10 2026 Strong high pressure building over the northwest region will bring unseasonably warm temperatures across the area on Sunday, with valleys expected to reach the lower 90s for the first time this year. A weak shortwave trough passing north of our area will bring strong wind gusts up to 35 mph over east-central OR near Baker County and northern Malheur County late Sunday night into early morning Monday. A slight cooldown is expected Monday, with peak temperatures expected to hover in the mid 80s. A powerful ridge of high pressure will quickly build into the entire western CONUS on Tuesday, bringing exceptionally warm temperatures over our area. Most valley areas are expecting to see peak temperatures in the mid to upper 90s, likely breaking daily records. The ridge may steer some upper moisture over the Great Basin late Tuesday, potentially favoring some high clouds and scattered dry thunderstorms over the ID/NV border area. && .LONG TERM /Wednesday through Sunday/... Issued 232 AM MDT SUN MAY 10 2026 A trough will approach the region on Wednesday with southerly flow over the area. Subtropical moisture will move northward from Baja on Wednesday, with precipitable water values reaching the 90th percentile. This combined with the trough moving inland will trigger scattered showers and thunderstorms on Wednesday afternoon and evening. Forecast precipitation should be higher than what is in there. Shear values are sufficient too for a severe weather threat with a few organized strong storms possible. The trough moves inland over southeast OR and southwest ID on Thursday with good model agreement. The current WPC/NBM forecast does not reflect this trough, so temperatures are around 10 to 15 degrees too warm for this event and probability of precipitation should be rain likely for most of the area on Thursday. Cooler temperatures continue into Sunday behind the trough with zonal flow over the area. Current forecast is too warm Friday through Sunday. && .AVIATION /12Z Sunday through Monday/... Issued 624 AM MDT SUN MAY 10 2026 VFR. Surface winds: SW-SE 10kt this morning increasing to 10-20kt this afternoon, becoming NW 10-20kt this evening with gusts up to 30kt near KONO KBKE after sunset. Winds aloft at 10kft MSL: SW 15-25kt. KBOI...VFR. SE winds 10-20kt becoming NW 10kt after sunset. && .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 AVIATION.....KA SHORT TERM...JY LONG TERM....KA

844 FXUS65 KLKN 100736 AFDLKN Area Forecast Discussion National Weather Service Elko NV 1236 AM PDT Sun May 10 2026 .KEY MESSAGES... * High pressure produces warm and dry weather thru most of the week * Record high temperatures are expected beginning Sunday and persisting thru Wednesday * Gusty winds across the forecast area and a low chance for rain showers and thunderstorms north of I-80 Wednesday && .UPDATE... Issued at 1232 AM PDT Sun May 10 2026 No major changes to the forecast needed, though model runs continue to add moisture and potential precipitation to areas north of I-80 on Wednesday. The forecast continues to track toward record breaking heat Sunday through Wednesday. && .DISCUSSION... (Today through next Sunday) WEATHER PATTERN OVERVIEW: Hot and dry weather conditions will be situated over the Great Basin thru early next week as an upper level ridge resides over the western U.S. and Canada. High pressure will build over the desert southwest region with daytime high temperatures residing 15 to 20 degrees warmer than normal by Sunday, persisting thru Wednesday. This will bring readings into the low 90s for some locales with daily high temperature records expected to be tied or broken at some climate sites. Progressive upper wave pattern brings a trof thru the PacNW Wednesday with the ridge moving east. The trof will clip northern Nevada and a low chance (10% to 20%) of afternoon rain showers and thunderstorms have been introduced to the forecast. A slight change from previous forecasts as most recent numerical model solutions are now bringing the trof thru the PacNW slightly further south. Not expecting any significant rainfall accumulation at this time and the most likely fare Wednesday afternoon will be cumulus buildups, virga, and the odd dry thunderstorm or two with most activity focused over the high terrain. This will also signal the start of a gradual cooling trend thru the latter half of next week under a westerly flow regime. By Friday, daytime high temperatures will be near to slightly warmer than seasonal values. Weather continues to look dry. Otherwise the typical afternoon breezes return Monday and Tuesday with stronger winds present Wednesday afternoon as the afore mentioned upper level trof clips Nevada. Elevated west- southwesterly winds will be present with gusts 30 to 40 mph Wednesday. The higher end gusts will be situated across Central Nevada. FORECAST CONFIDENCE & DEVIATIONS: There is high confidence for warm temperatures and dry conditions thru early next week. Low confidence regarding the prospect of showers and thunderstorms Wednesday afternoon. Minimal deviation from NBM with temperatures adjusted a few degrees cooler in the typical colder valleys across the forecast area. && .AVIATION... VFR conditions remain in place thru Sunday afternoon under mostly sunny and clear skies with a few high level clouds overhead at times. Winds will again be generally light Sunday afternoon. && .FIRE WEATHER... Relatively benign yet warm weather Sunday will give way to hot, dry, and breezy conditions early next week as high pressure builds across the desert southwest region thru this weekend under the influence of an upper level ridge. Elevated fire weather concerns will be present as temperatures warm 15 to 20 degrees warmer than normal beginning Sunday, carrying thru Wednesday. Daily high temperature records are expected to be tied or broken early next week. The typical afternoon breezes will be present by Monday and Tuesday with gusts around 20 mph. This will combine with minimum afternoon relative humidity values of less than 15%. Stronger wind event expected Wednesday afternoon with west- southwesterly gusts 30 to 40 mph and the higher end gusts will be situated across Central Nevada. have also introduced isolated showers and thunderstorms into the forecast for locations north of the I-80 corridor Wednesday afternoon as an upper level trof moving thru the PacNW clips Nevada. Not expecting any significant rainfall accumulation at this time and the most likely fare Wednesday afternoon will be cumulus buildups, virga, and the odd dry thunderstorm or two with most activity focused over the high terrain. && .LKN Watches/Warnings/Advisories... None. && $$ UPDATE...99 DISCUSSION...92 AVIATION...92 FIRE WEATHER...92