403 FXUS66 KSEW 110435 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 935 PM PDT Thu Jul 10 2025 .UPDATE...Satellite imagery shows just a few clouds out there this evening with a stratus deck just off the coast. Surface gradients are flat and will remain flat overnight into Friday. Dew points over the interior are down 5 to 10 degrees so even with just afternoon sunshine the air mass over the interior dried out today. Expecting the stratus to stay west of Puget Sound Friday morning. More sunshine combined with warming aloft will give most places high temps 5 to 10 degrees warmer than today. Current forecast in good shape. No update tonight. && .PREV DISCUSSION... /issued 301 PM PDT Thu Jul 10 2025/ .SYNOPSIS...High pressure returning to the region will result in an extended period of warm and dry conditions that will persist well into next week. Temperatures are expected to peak Tuesday into Wednesday, where temperatures could reach the low to mid 90s for many areas. .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...As expected, the deeper marine layer today has helped the stratus linger well into the afternoon. Ceilings have been lifting and starting to scatter all along the I-5 corridor with some blue sky leading into the evening hours for most areas outside of the coast. High temperatures along the coast today will remain in the mid 60s, with temperatures in the lower 70s through the inland areas. The offshore upper level ridge will tip into the Pacific Northwest Friday with less morning stratus and a bump to temperatures - back into the lower to mid 80s across much of the interior lowlands. Lingering, albeit weaker onshore flow will maintain cloudy skies along the Pacific coast with mostly clear and dry conditions elsewhere. A weak upper level wave riding the ridge Saturday will bring a few extra clouds high clouds especially along the northern border, but ultimately very similar conditions - warm and dry with highs in the 80s over the interior and near 70 along the coast. .LONG TERM /SUNDAY THROUGH THURSDAY/...Conditions on Sunday into Monday look to begin trending warmer as high pressure continues to build offshore, with high temperatures working more into the upper 80s. Some of the ensembles do show perhaps a bit of a brief pause to the warming trend Monday - with highs still in the mid to perhaps upper 80s. NBM continues to highlight temperatures peaking Tuesday into Wednesday. For Tuesday widespread areas over the interior south of Puget Sound into the Cascade valleys and foothills having an 80-85% chance of high temperatures at or above 90. This will expand Wednesday - extending northward through the Kitsap Peninsula, Western King and Snohomish Counties. In addition to the very warm daytime temperatures, overnight lows in the metro area will start to struggle to cool below 60 degrees Monday night into Tuesday morning. This will broaden to most of the interior overnight Tuesday night and again Wednesday night. The overall warming trend will result in widespread Moderate (orange) HeatRisk to western Washington by Tuesday with local areas of Major (red) HeatRisk. Some degree of cooling is now indicated for Thursday - but temperatures will likely remain in the 80s over much of the interior - still well above normal. .AVIATION...Tonight stratus will be mostly confined to the coast, SW interior and bits hugging the Cascades. IFR to LIFR cigs developing along the coast 06z-09z with mist possibly limiting visibility. Stratus will retreat to the immediate coastline by 18z Friday with VFR for all interior terminals expected. Winds becoming NW this evening and maintain a northerly component into Friday between 5-10 kt (lighter overnight). KSEA...VFR conditions through Friday. There`s a small ( 20% ) chance of MVFR cigs between 13-16z Friday. North northwest wind 6 to 10 knots becoming northeast 4 to 8 knots after 09z. Winds switching back to north northwest 6 to 10 knots around 18z. McMillian/Felton .MARINE...Flow turning NW over the coastal waters this evening as a surface high sits well offshore. Benign seas tonight but a shallow marine layer could lead to patchy fog over area waters into Friday morning. For Friday, onshore flow looks to increase and become strong. SCA winds for the central and eastern Strait of Juan de Fuca Friday evening into early Saturday morning. Diurnal pushes are favored throughout the Strait this weekend and could reach advisory levels. A trough passing to the north early next week may produce gusty winds in the outer coastal waters, along with steeper seas. Seas will range 3-5 feet through Friday, increasing to 6 to 8 feet over the weekend, couple spots further offshore may see 10 feet seas into early next week. McMillian .FIRE WEATHER...Mostly clear skies tonight as high pressure begins to build over the region, signaling the beginning of a prolonged warming and drying trend from Friday through next week. Friday will be notably dry, with RH values dropping back into the 25- 35% range over the mountains as well as the interior lowlands south of the Puget Sound. More robust onshore flow this weekend will help usher in more moist air with min RHs back into the 30s and 40s, despite high temperatures remaining in the 80s. While there is still some model discrepancy over how warm and dry we get next week, there is consensus that the warm and dry will continue into the middle of next week, with the flow switching to offshore by Tuesday as a thermal trough begins to build along the coast. Fire weather concerns will be elevated beginning Tuesday as minimum RH values look to drop into the 20s across much of the Cascades and the interior lowlands south of Seattle. There may also be some locally breezy winds through the Cascade gaps. This patter will continue to be closely monitored as we approach next. 62 && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory from 3 PM Friday to 6 AM PDT Saturday for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory from 5 PM Friday to 5 AM PDT Saturday for Admiralty Inlet. && $$

476 FXUS66 KPQR 110347 AAA AFDPQR Area Forecast Discussion...UPDATED National Weather Service Portland OR 847 PM PDT Thu Jul 10 2025 Updated Aviation Discussion... .SYNOPSIS...Partly cloudy skies with seasonable temperatures this afternoon. Temperatures warm up tomorrow into the weekend as high pressure builds. Expect morning marine clouds along the coast and over the waters. Temperatures cool slightly on Monday, but still remain very warm and dry. An Extreme Heat Watch has been issued for some interior valley locations from Tuesday to Wednesday next week as temperatures between 95 to 105 degrees are possible with overnight lows struggling to fall below 65 to 70 degrees. && .SHORT TERM...Now through Saturday night...Satellite imagery as of early Thursday afternoon depicts partly cloudy skies and dry conditions across most of northwest Oregon and southwest Washington. Afternoon highs today are forecast to peak in the upper 70s to low 80s across interior locations, which is near or slightly below seasonal norms. Tomorrow (Friday), an upper level ridge begins to re-build, leading to warmer temperatures and sunny skies. Do expect some marine fog/stratus as high pressure aloft keeps clouds to the lowest part of the atmosphere. Friday afternoon highs are forecast in the upper 80s across interior valleys while the coast remains mild in the 60s to low 70s with onshore flow. Expect breezy northwesterly winds along the coast with gusts up to 25 mph, while northerly winds gust up to 20 mph across the Willamette Valley. The strongest winds will be in the afternoon when pressure gradients are tightest. High pressure persists on Saturday, maintaining similar temperatures to Friday with generally northerly flow. -Alviz && .LONG TERM...Sunday through Wednesday...Ensemble guidance suggests that high pressure this weekend peaks on Sunday, leading to very warm temperatures in the low to mid 90s across the Willamette Valley. This will lead to widespread Moderate HeatRisk - this level of heat affects most individuals sensitive to heat, especially those without effective cooling and/or adequate hydration. We will continue to evaluate if a Heat Advisory is warranted for this weekend (particularly Sunday). On Monday, temperatures fall about 5-10 degrees as most ensemble guidance suggests an upper level shortwave trough dipping into the Canadian Rockies and northern Intermountain West. Though 500 mb heights fall over our area with this shortwave trough, they still remain above-normal and will maintain warm temperatures with highs in the upper 80s to low 90s for interior valleys. All eyes are on Tuesday to Wednesday as there is potential for extreme heat. An Extreme Heat Watch has been issued from Tuesday afternoon (July 15) to late Wednesday evening (July 16) across the Greater Portland/Vancouver Metro, Western and Central Columbia River Gorge, the Corbett area and the Hood River Valley, Lower Columbia River and Cowlitz River Valleys, and Central Willamette Valley. Dangerously hot conditions with temperatures between 95 to 105 degrees are possible. Low temperatures between 65 to 70 degrees are possible as well, which would limit overnight relief especially Tuesday night. Currently, this Watch encompasses areas where overnight low temperatures may struggle to fall below 65 to 70 degrees. The latest guidance suggests that there is a 40-50% chance that Tuesday night low temperatures remain above 70 degrees. In addition, there is also a 20-40% chance that Tuesday and Wednesday high temperatures exceed 105 degrees across the Willamette Valley. As a reminder, an Extreme Heat "Watch" is issued when dangerous heat is possible. An Extreme Heat "Warning" is issued when dangerous heat is happening or about to happen. Major HeatRisk is currently forecast for areas within the Extreme Heat Watch. This level of heat would affect anyone without effective cooling and/or adequate hydration. Heat related illnesses increase significantly during extreme heat events. In addition to the upper level high pressure, models are also indicating a thermal trough developing over the Willamette Valley on Tuesday. If this occurs, then it would lead to more offshore flow. Currently, the easterly winds forecast with this thermal trough are not looking very strong, and will mainly be through the Columbia River Gorge and Cascades. Current guidance shows pressure gradients of -2 to -4 mb through the Gorge on Tuesday, which would lead to wind gusts up to 20-25 mph in that area. -Alviz && .AVIATION...Westerly flow continues across the airspace through the TAF period, resulting in similar conditions as to what has been observed over the past 24-48 hours. Expect coastal conditions to redevelop around 04-06Z Friday, resulting in a mix of IFR/LIFR conditions overnight and into early tomorrow morning. Inland will experience mostly northerly flow, which will likely prevent any marine stratus from pushing inland (through Coast Range gaps and Columbia River). However, could see clouds backbuilding off the Cascades and bringing MVFR conditions to inland terminals. While models have been suggesting the backbuilding of MVFR clouds, each new model run looks less likely to backbuild enough to reach inland terminals. If these clouds build off the Cascades, expect MVFR conditions to affect inland terminals between 13-16Z Friday. Conditions will slowly improve across the airspace thereafter. PDX AND APPROACHES...Expect VFR conditions and northwesterly flow through most of the TAF period. There is the possibility of clouds backbuilding off the Cascades between 13-16Z Friday, which would likely result in MVFR conditions at the terminal. While low confidence, if clouds backbuild off the Cascades and bring MVFR conditions to the PDX terminal, expect conditions to improve back to VFR by 17Z Friday. Expect northwesterly winds 5-10 kt becoming 08-12 kt with gusts up to 20 kt by 18Z Friday. ~Hall && .MARINE...North/northwest winds across all waters will persist through the weekend as a broad area of high pressure and a thermally induced trough spreads northward. As the high pressure and associated thermally induced trough mature, expect gusty northerly winds and choppier wind driven seas. As a result have issued a Small Craft Advisory for Zones PZZ273, PZZ253, PZZ272, and PZZ252 starting Friday morning and continuing through at least early Saturday morning. /42 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Extreme Heat Watch from Tuesday afternoon through Wednesday evening for ORZ108>115-119>122. WA...Extreme Heat Watch from Tuesday afternoon through Wednesday evening for WAZ204>207-209-210. PZ...Small Craft Advisory from 2 PM to 11 PM PDT Friday for PZZ252- 272. Small Craft Advisory from 11 AM Friday to 2 AM PDT Saturday for PZZ253-273. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

354 FXUS66 KMFR 110105 AFDMFR Area Forecast Discussion National Weather Service Medford OR 605 PM PDT Thu Jul 10 2025 .UPDATE...Updated Aviation Discussion. && .AVIATION (00Z TAFs)...Coastal IFR/LIFR is expected to return north of Cape Blanco early this evening, and expand into the Coquille Valley overnight. Low clouds will lift and clear in the late morning and early afternoon, with VFR returning along the coast. Gusty afternoon winds are expected along the coast Friday. Elsewhere, VFR will persist with breezy late afternoon and evening northwest winds. -CC && .PREV DISCUSSION... /Issued 306 PM PDT Thu Jul 10 2025/ DISCUSSION...The main updates today were: to upgrade the Extreme Heat Watch for Josephine, Jackson, and western Siskiyou counties on Saturday through Monday to an Extreme Heat Warning, issue a Heat Advisory for the remainder of our area, excepting the coast, and southern Oregon Cascades and Siskiyou Mountains, and add a slight chance mention for thunderstorms into western Siskiyou County into Sunday afternoon/evening. There are areas of high pressure far offshore and over southern California that are both building toward our area. Of the two, the southern ridge will be the more impactful/more responsible for our coming heat wave. Meantime, a very weak trough, in-between the ridges will move east across Siskiyou County on Sunday. This is not an impressive feature, but warrants the inclusion of the slight chance of late day thunderstorms for western Siskiyou County with the 12Z GFS indicating the best chance of a storm to pop up near Fort Jones. With more of a westerly flow aloft, and absence of a shortwave trigger, expect following days to be less favorable for any thunderstorm development, but patchy lower topped cumulus clouds will still be possible over the higher terrain. The extreme heat Saturday through Monday with result in inland highs from the lower 90s to around 110, with the hottest readings, as usual, in the valleys of western Siskiyou County. Model agreement diminishes beyond Monday, with a balance between slight cooling or slight further heating for Tuesday and Wednesday. An inside slider trough tracking across eastern Washington to the Rockies may have a lobe break off and retrograde offshore. This will either put a small dent in the strength of the ridge, or the ridge will quickly rebound in strength behind the trough. Even if we do end up with the `cooler` solution, temperatures would still be several degrees above normal. MARINE...Updated 200 PM PDT Thursday, July 10, 2025...A thermal trough will intensify today, bringing gusty north winds and steep wind-driven seas across area waters. By this evening, winds and seas will expand north of Cape Blanco with gales and very steep seas developing to the south. The strongest winds and steepest seas will be south of Port Orford. This pattern will continue through the weekend and into early next week as the thermal trough maintains position across the region. -BPN FIRE WEATHER...Updated 200 PM PDT Thursday, July 10, 2025... After warm, slightly above normal temperatures today, heat will return to the region this weekend into early next week as upper level ridging builds in aloft and an thermal trough develops at the surface. Meanwhile, expect fairly typical late-day summertime breezes, but also dry afternoon humidity. Also, a general easterly/offshore flow is forecast to develop over the coastal mountains and Klamath/Siskiyou mountains each night, which may result in moderate to locally poor RH recoveries, especially over the ridgetops where overnight gusts could reach up to 25 mph. This will not be a necessarily strong east wind pattern, but it will be sustained for several days. While there are no substantial threats for thunderstorms through hat least the middle of next week, a passing weak impulse will help produce some weak instability over the area Sunday afternoon. As a result, we will see some cumulus cloud buildups across the area, and perhaps a stray shower or very isolated thunderstorm over southwestern Siskiyou county. Most likely, the entire area will be dry, but some plumes and pyro-cumulus development is possible under these potential hot, dry, and unstable conditions. -BPN && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Extreme Heat Warning from 2 PM Saturday to 8 PM PDT Monday for ORZ024-026. Heat Advisory from 2 PM Saturday to 8 PM PDT Monday for ORZ023- 025-029>031. CA...Extreme Heat Warning from 2 PM Saturday to 8 PM PDT Monday for CAZ080-081. Heat Advisory from 2 PM Saturday to 8 PM PDT Monday for CAZ082>085. PACIFIC COASTAL WATERS...Gale Warning until 8 PM PDT Saturday for PZZ356-376. Small Craft Advisory until 8 PM PDT Saturday for PZZ350-370. && $$

123 FXUS66 KEKA 102153 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 253 PM PDT Thu Jul 10 2025 .SYNOPSIS...High pressure is building and generally hot and dry weather is expected for the next week or so. The hottest temperatures will start in the south on Friday and work their way north on Saturday and Sunday. Northeast winds overnight on Thursday and Friday will help to limit the stratus and potentially bring warmer temperatures to the coast. && .DISCUSSION...High pressure continues to build over the area and hot temperatures are starting to take hold in Mendocino county. A thin strip of stratus remains in place as of 2pm along portions of the coast. If this clears out it may take considerable time to come back tonight. Offshore flow tonight is expected to limit the coverage of clouds up the river valleys and this should facilitate skies clearing on coast. The heat advisories start Friday afternoon in Mendocino and Lake counties as the temperatures warm more quickly down there, although there is quite a bit of warming in the north as well and the argument could be made to start the advisories in Humboldt and Del Counties as well. Trinity county warms more Saturday as this heat continues to build. This is expected to be the start of a more extended period of hot weather so have issued an excessive heat warning. Sunday the ridge starts to shift east slightly and it looks like this will allow some marine air to start to intrude on Mendocino county. This may also bring some stratus to the immediate Mendocino coast. So the heat advisory ends for the Ukiah and Willits zones on Saturday evening. Also on Sunday the models are showing some increasing moisture aloft and the potential for a thunderstorm over northern Trinity county. For now this only looks to be around a 10 percent chance, but did add that to the forecast. One potential challenge in this forecast is the presence of smoke may keep temperatures cooler than expected. General went with the idea that the smoke would not be sufficient to keep temperatures cooler over a large area. Monday the ridge continues to shift east and the marine layer may start making its way north and starting to cool off portions of Humboldt and Del Norte counties. There is still some uncertainty on how much of the heat will linger in eastern Mendocino and Lake counties so the advisories may need to be extended there. Tuesday hot weather continues, but it is expected to be more confined to areas well away from the coast in Trinity county. Wednesday an upper level trough approaching the area continues the slow cooling trend, but most areas are expected to still be in the 90s. MKK && .AVIATION...Stratus along the Del Norte and Humboldt coasts has started to lift and scatter early this afternoon. Breezy northerly winds are likely this afternoon and evening, with strong winds at CEC possibly exceeding 25 kts. Mostly clear skies will follow for across the area into the evening, apart from wildfire smoke. Stratus is likely to return this evening and overnight to the Humboldt coast, with a shallow marine layer bringing LIFR/IFR ceilings and visibilities. Northerly winds will likely ease overnight for most of the area, aside from CEC. Southerly winds are possible along the immediate coast between ACV and CEC, which would advect stratus northward. If northerlies remain strong overnight at CEC, stratus will likely hit a barrier before affecting the terminal. NBM is showing around a 60% chance for IFR or LIFR ceilings and visibilities for CEC. Interior areas, including UKI, are expected to remain clear aside from smoke and haze. JB && .MARINE...Northerly winds have started to ramp up as a tight pressure gradient sets up along the coast. Gale force gusts are likely in the outer waters starting this afternoon into Friday. Nearshore waters could see gusts of 20-25 kts in the afternoons, but are largely insulated from the strongest winds. Steep, elevated seas in the outer waters are likely to in nearshore Friday afternoon, bringing steep seas of 8-10 ft. Winds begin to move further offshore Saturday, especially south of Cape Mendocino. North of the Cape, near-gale to gale force winds are likely to continue into early next week. High pressure begins to break down by mid next week, which will likely ease winds and seas. JB && .FIRE WEATHER...High pressure is building and offshore flow is expected with the warming and drying inland and near coastal areas. This is keeping just a very thin strip of stratus along the coast this afternoon and even this may erode later this afternoon. Areas below the marine layer inversion, which is currently around 2500 feet, are expected to see good RH recoveries while areas above it will be much drier and see breezy northeast to east winds. This inversion is expected to lower over the next couple days as high pressure strengthens. The NBM is likely too high on the rh due to the pattern shift from a deep marine layer. So it has been lowered it by blending it with the FV3 model. This may not be low enough, but it appears to push it in the right direction. 850 and 925 mb winds are around 10 to 20 mph overnight with rh recoveries only around 40 to 50 percent on the ridges again. Warmer dry conditions are generally expected on Saturday, although portions of Mendocino county closer to the coast may start to see more marine influence as the flow aloft weakens starting on Saturday. Smoke across the area will mainly be pushed south from the Butler Fire. This will trend more towards the west overnight and back to the east in the afternoon when the winds become more northwesterly. The eastern portions of the area may also see some smoke from the Green Fire north of Redding in the afternoons. This general pattern is expected to continue over the next several days depending on how much smoke the fires output. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Extreme Heat Watch from Saturday morning through Sunday evening for CAZ102-105-106. Heat Advisory from 11 AM Friday to 11 PM PDT Sunday for CAZ107-108-111-114-115. Heat Advisory from 11 AM Friday to 11 PM PDT Saturday for CAZ110-113. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 11 AM PDT Saturday for PZZ450. Small Craft Advisory until 3 AM PDT Friday for PZZ455. Gale Warning until 11 PM PDT Saturday for PZZ470. Gale Warning until 11 AM PDT Saturday 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

966 FXUS66 KMTR 110416 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 916 PM PDT Thu Jul 10 2025 ...New UPDATE... .KEY MESSAGES... Updated at 1208 PM PDT Thu Jul 10 2025 - Inland temperatures roughly 10 degrees warmer than yesterday, bringing moderate HeatRisk through Friday. - Localized elevated fire weather threat continues across higher elevations. - Gradual cooling trend next week. && .UPDATE... Issued at 916 PM PDT Thu Jul 10 2025 The marine layer remains compressed around 1000 feet with stratus filtering in along the coastline. Inland stratus coverage is expected to be much less widespread tonight than it has been earlier this week as high pressure continues to build over the region. Warmer and drier weather continues again tomorrow with highs expected to be similar to today`s (upper 80s to 90s). A cooling trend remains on track for this weekend with no major changes to the overall forecast. && .SHORT TERM... Issued at 1208 PM PDT Thu Jul 10 2025 (This evening through Friday) Byron airport in far eastern Contra Costa County crossed into the 90s by noon, but most inland stations are still reporting 70s and low 80s. Some smoke is propagating into the region, mainly from the Green Fire in Shasta County. This will filter and reflect some of the sunlight and should take the edge off the heat today. Our latest short term forecast keeps the warmest areas generally in the mid 90s both today and Friday. While these temperatures are only 5-10 degrees above normal, it may feel worse than that since we just finished a cool period. Coastal areas will stay in the 60s and 70s thanks to onshore wind. The marine layer has compressed to 1,000 feet, which will keep overnight clouds confined closer to the coast and they should evaporate faster than normal Friday morning. && .LONG TERM... Issued at 1208 PM PDT Thu Jul 10 2025 (Friday night through next Wednesday) There is high confidence that the pattern will remain fairly stable through early next week with high pressure anchored near the Channel Islands, embedded in broad high pressure across the Eastern Pacific. While this high pressure will cause the 850 temp to build to the 90th percentile for mid-July, we are actually going to cool off a bit this weekend. The overall pattern supports onshore wind. With high pressure offshore and to our south, both downgradient and geostrophic winds are onshore. This synoptic forcing is enhanced each day as the thermal trough over the Central Valley deepens. The pressure gradient from SFO to SAC is expected to fluctuate from +1 mb at night to +4 mb during the day through early next week. This happens because the ridge brings afternoon temperatures around 100 degrees in the Central Valley. This hot air rises and literally lifts a weight off the lower atmosphere. This induced low pressure then pulls in air from the Bay Area like a vacuum. With ocean waters in the mid-50s, the onshore winds act as a natural air conditioning, keeping us much cooler. By the middle of next week, it looks like a trough will disrupt the pattern and cool things off across the state. In the super-long range, there is some indication that a 4-corners high will start to build around July 22-24, which could bring more impactful heat late in the month. && .AVIATION... (00Z TAFS) Issued at 522 PM PDT Thu Jul 10 2025 IFR and LIFR CIGS are building along the coast and are affecting HAF. Expect winds to reduce into the evening and become light for most areas. IFR CIGs arrive to the Monterey Bay Terminals in the mid evening and fall to LIFR into the night with mist and drizzle affecting the immediate coast and slightly inland terminals. IFR CIGs arrive at APC in the late night and LIFR CIGs and fog affect STS into the morning. Inconsistent IFR CIGs will move around the SF Bay in the late night and into Friday morning, affecting SFO and OAK. Fog will also form around the MRY into Friday morning.Clearing begins in the mid morning with most TAF sites going VFR in the mid to late morning. The exception will be HAF, which keeps CIGs through the TAF period. Winds look to stay light to moderate through much of the morning, but will increase into the late morning morning and afternoon. Expect winds to reduce into Friday evening. Vicinity of SFO...VFR lasts through the late night. Winds stay breezy into the late evening before becoming light to moderate. IFR- level clouds shift through the SF BAY in the late night, and look to inconsistently fill over SFO and OAK before exiting into early Friday. Breezy west winds return in the late morning, and look to last through the mid evening before becoming light again. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...IFR CIGs are building in the Bay and look to fill over the terminals as winds reduce into the evening. Light winds last through the night with CIGS falling to LIFR and pockets of mist and drizzle affecting visibilities into the mid morning morning. Moments of fog also look to affect MRY. Winds become moderate into mid Friday morning as CIGs erode over the terminals, but expect cloud cover to linger over the Monterey Bay itself until && .MARINE... (Tonight through next Wednesday) Issued at 522 PM PDT Thu Jul 10 2025 Strong northerly breezes over the outer waters will continue through Saturday with the most hazardous conditions in the far northwestern portion with gale force gusts and very rough seas. Sunday and Monday will have a gentle breeze with moderate to rough seas. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory until 3 AM PDT Friday for Pt Arena to Pt Reyes 0-10 nm. Gale Warning until 9 AM PDT Friday for Pt Arena to Pt Reyes 10- 60 NM. Small Craft Advisory until 9 AM PDT Friday for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...Flynn LONG TERM....Flynn AVIATION...Murdock MARINE...Sarment 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

488 FXUS66 KOTX 102241 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 341 PM PDT Thu Jul 10 2025 .KEY MESSAGES... - Cooler and locally breezy through Thursday evening. - Warming trend returns Friday with above normal temperatures through this weekend. && .SYNOPSIS... After a brief cooldown on Thursday, warm temperatures will return over the weekend. Conditions will remain dry and winds will be locally breezy each afternoon across Central Washington. && .DISCUSSION... Thursday afternoon through Sunday: As an upper level trough tracks across the northeast corner of the region, winds will shift from west to northwest late Thursday afternoon and evening. In addition to the wind shift, the wave will bring just enough instability to keep chances for isolated showers over the northern ID Panhandle through the evening. Heading into the overnight hours, drier northerly air will result in clearing skies. As the trough exits the region and ridging rebuilds, temperatures will begin climbing Friday and will increase by a few degrees each day through the weekend, reaching the mid 90s to just over 100 degrees by Sunday. Thermally induced low pressure at the surface in the afternoons will create a cross-Cascade pressure gradient and will cause westerly winds to pick up each afternoon and evening through the Cascade gaps into the western Columbia Basin. Monday through Wednesday: The majority of model solutions are in agreement on a system moving in early next week, bringing cooler temperatures and an increase in winds which will lead to elevated fire weather concerns. Uncertainty remains as to how strong the system will be and exactly how much of an increase in winds it will bring. We will continue to monitor fire weather conditions for this time period. /Fewkes && .AVIATION... 00Z TAFS: VFR conditions are expected to continue for all TAF sites through 00z Saturday. Winds will remain locally breezy with gusts of 15-25 kts through Thursday evening. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence that VFR conditions will continue at all TAF sites. The Hope and Western Pines Fires over NE Washington could advect some smoke into the Spokane/Coeur d`Alene area Thursday evening, though visibility at the surface is not expected to drop below 6 mi. ----------------------- 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 56 89 60 93 63 96 / 0 0 0 0 0 0 Coeur d`Alene 55 87 59 91 63 94 / 0 0 0 0 0 0 Pullman 51 85 54 89 58 91 / 0 0 0 0 0 0 Lewiston 64 95 66 99 69 101 / 0 0 0 0 0 0 Colville 44 87 50 92 53 96 / 0 0 0 0 0 0 Sandpoint 51 84 54 88 57 90 / 0 0 0 0 0 0 Kellogg 58 84 62 87 65 90 / 0 0 0 0 0 0 Moses Lake 60 93 61 97 65 100 / 0 0 0 0 0 0 Wenatchee 63 93 68 96 71 99 / 0 0 0 0 0 0 Omak 56 92 62 96 65 99 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

659 FXUS66 KPDT 102325 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 425 PM PDT Thu Jul 10 2025 Updated Aviation Discussion .AVIATION...00Z TAFs...VFR conditions to prevail through the period. Breezy winds 10-20kts with gusts 20-30kts will prevail through this evening at sites DLS/PDT/YKM, then redeveloping at site DLS after 20Z. Otherwise, winds will generally be 12kts or less through the period. Lawhorn/82 && .PREV DISCUSSION... /issued 126 PM PDT Thu Jul 10 2025/ SHORT TERM...Today through Saturday...Breezy conditions prevail through the Cascade Gaps and into the Basin this afternoon in the wake of an upper-level trough that brought stronger winds to the forecast area last night. Once this system is out of our area of influence, a dry and hot pattern will take hold through at least the midweek next week. Until then, expect relatively seasonable temperature readings, with the heat initially starting to ramp up on Saturday. RHs will drop off over the weekend as a result of this building heat, stemming from a broad ridge building over the PacNW, but this ridge will help even out pressure gradients, keeping winds primarily thermally-induced through the Cascade Gaps. The expectation, however, is that winds will not be strong enough to cause critical fire weather conditions, at least in the short term. Evans/74 LONG TERM...Sunday through Thursday...Heat continues through the first half of next work week, with temps expecting to peak on Sunday with highs over 100 across much of the Basin, before deterministic guidance depicts a shortwave clipping us to our northeast on Tuesday. While this system is not anticipated to bring us any rain, it will remain significant for firefighting efforts in the sense that it will bring about a distinct wind change to the north and northeast after days of more typical westerly flow. Models as of now are not projecting particularly strong winds, but any distinct wind shift, especially toward the east, can greatly hinder firefighting coordination. Ensembles are a bit divided over what occurs synoptically Wednesday onward, but the general consensus appears to lean toward that of a progressive and relatively zonal pattern. Clustering, however, does not provide enough detail to go too much into detail on how the forecast is expected to evolve beyond the midweek next week, other than to at the very least expect a continuation of above-normal temperatures, breeziness through the Cascade Gaps, and little to no rain threats for the time being. Evans/74 && .PRELIMINARY POINT TEMPS/POPS... PDT 59 91 62 97 / 0 0 0 0 ALW 63 91 66 95 / 0 0 0 0 PSC 59 94 63 98 / 0 0 0 0 YKM 59 93 65 98 / 0 0 0 0 HRI 60 94 63 99 / 0 0 0 0 ELN 58 93 65 93 / 0 0 0 0 RDM 48 88 51 95 / 0 0 0 0 LGD 56 87 57 92 / 0 0 0 0 GCD 53 89 54 93 / 0 0 0 0 DLS 62 93 65 95 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...74 LONG TERM....74 AVIATION...82

535 FXUS65 KREV 102024 AFDREV Area Forecast Discussion National Weather Service Reno NV 124 PM PDT Thu Jul 10 2025 .KEY MESSAGES... * Prolonged heat wave begins Friday with highs reaching 100-105 degrees in western Nevada valleys and 85-93 degrees in the Sierra. * Little overnight relief expected, especially in urban areas, increasing heat-related illness risk. * Smoke and haze from wildfires in northern CA and southern OR may impact air quality and visibility into the weekend. && .DISCUSSION... Hazy conditions, carrying over from the morning, will slowly dissipate today with the return of typical zephyr breezes (gusts up to 20-25 mph). However, with fires continuing in northern CA and southern OR, expect hazy conditions to continue overnight and into the morning hours this weekend. To check air quality, visit www.fire.airnow.gov. The main story will be an ongoing heat wave through early next week. Locations across the area will see the hottest temperatures of the year so far; far W NV valleys seeing highs up to 105 degrees, the Quad Counties area experiencing 98-104 degrees, Sierra communities in the low 90s, and locations in NE CA pushing 103 degrees. Reno will see its first 100 degree day of the year so far as early as Saturday, with a 75% chance of exceeding 100 degrees. We could also near record-breaking territory Sunday; the forecasted high for Reno is 102 while the record, set in 2014, is 103 degrees. Areas of widespread Moderate HeatRisk Saturday will quickly evolve into Major HeatRisk by Sunday as afternoon highs peak Sunday and Monday across the area. Isolated areas of Extreme HeatRisk are possible both Sunday and Monday, primarily in W NV valleys east of Fernley. Heat recoveries will be poor, with overnight lows pushing the upper 60s and low 70s for W NV this weekend, bringing little overnight relief. Besides typical afternoon zephyr breezes, winds will be light. With the increase in heating this weekend, there will also be increased instability. The next best chance (<10% chance) for afternoon showers and thunderstorms will be next Tuesday through Friday. Stay tuned for more details as we get closer. -Giralte && .AVIATION... VFR conditions prevail, but areas of haze or smoke may impact far northwest Nevada and northeast California, especially near the CA/OR border through this weekend. Otherwise, SW winds gusting 20-25 kt each afternoon, coinciding with the afternoon zephyr. Density altitude conditions will become increasingly hazardous Sunday through Tuesday due to elevated temperatures and high field elevations. Expect reduced aircraft performance during peak heat, particularly for high-elevation takeoffs and landings. -Giralte/Johnston && .REV Watches/Warnings/Advisories... NV...Heat Advisory from 11 AM Sunday to 11 AM PDT Wednesday NVZ001- 003>005. CA...Heat Advisory from 11 AM Sunday to 11 AM PDT Wednesday CAZ070. && $$

946 FXUS66 KSTO 102135 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 235 PM PDT Thu Jul 10 2025 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .DISCUSSION... .SYNOPSIS... Hot weather is expected through Monday with Moderate to locally Major HeatRisk. Some Delta breeze influence will bring minor cooling over the weekend and into next week in the Delta and adjacent Valley locations. Dry and periodically breezy northerly winds are expected through Friday, with breezy onshore winds next at times next week. && .KEY MESSAGES... * Today-Friday: - Upper level high pressure ridge continues to build, resulting in dry conditions and warming temperatures - Widespread Moderate HeatRisk with areas of Major HeatRisk across interior NorCal - Smoke will continue to impact areas in the vicinity of the Green Fire, with northerly winds spreading smoke and haze southward through the Valley into Friday - Locally breezy northerly flow in the northern/central Sacramento Valley and adjacent terrain, mainly in the overnight through morning timeframe - Low daytime relative humidity with moderate to poor overnight recoveries over foothills and mountains * Saturday-Monday: - Continued hot and dry conditions, with widespread Moderate HeatRisk and areas of Major HeatRisk in the forecast for interior NorCal into early next week - There will be some Delta breeze influence over the weekend and into next week that will allow for minor cooling in the Delta vicinity - Upper level ridging looks to continue to be the dominating weather pattern into next week * Tuesday - Cooling trend begins with Minor to Moderate HeatRisk .Changes from previous forecast... - Temperatures and HeatRisk have trended higher for Monday - The Heat Advisory north of Interstate 80 in the Valley, foothills and mountains beginning Friday at 11 am PDT has been extended and now continues through Monday evening 11 pm PDT. && .AVIATION... VFR conditions across interior NorCal next 24 hours. Periods of breezy onshore winds with gusts up to 15 to 20 knots in the Delta vicinity through 12z Friday. Elsewhere, sustained speeds generally less than 12 knots over the next 24 hours, with gusts less than 15 kts. Local MVFR conditions possible at times in HZ/FU vicinity of Shasta County wildfire, including KRDD. && .STO WATCHES/WARNINGS/ADVISORIES... Heat Advisory from 11 AM Friday to 11 PM PDT Monday for Burney Basin / Eastern Shasta County-Central Sacramento Valley- Mountains Southwestern Shasta County to Western Colusa County- Northeast Foothills/Sacramento Valley-Northern Sacramento Valley- Shasta Lake Area / Northern Shasta County-Western Plumas County/Lassen Park. && $$

940 FXUS65 KMSO 101944 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 144 PM MDT Thu Jul 10 2025 .DISCUSSION... KEY MESSAGES: - Warming trend Friday into the weekend, with moderate heat risk impacts across low elevations of central Idaho. - Next system arrives Monday into Tuesday, with potential for backdoor cold front, northeast winds, and recreation impacts. GOES Satellite and radar observations this afternoon show a upper level disturbance moving across southern Alberta, with scattered showers across northern portions of Lincoln and Flathead Counties. Blustery westerly winds have began to surface, with gusts expected to reach 25-30 mph across valley areas through this evening across western Montana. Higher gusts near 40 mph have been observed across high elevations along the divide in northwest Montana, including Logan Pass in Glacier Park. Showers will continue through this evening across northwest Montana, focusing across Glacier Park, with enough moisture and instability being present for a couple isolated thunderstorms. A ridge of high pressure will amplify along the Pacific Northwest coast Friday into the weekend. This will place the Northern Rockies under a warm and dry west-northwest flow pattern. Confidence is high for rising temperatures through the weekend, with highs reaching into the upper-90s to low-100s across lower elevations of central Idaho. These temperatures will stretch over the weekend, leading to a moderate risk of heat impacts. Temperatures will also run 10-15F above normal across western Montana, with Sunday being the warmest day of the upcoming week. Ensemble models continue to suggest a breakdown of the ridge Monday into Tuesday next week as a trough drops southeastward from British Columbia. Half of ensemble clusters bring a strong backdoor cold front southward from Canada across the divide Monday evening into Tuesday morning, with north-northeast winds developing across western Montana. Guidance has trended towards this solution, with previous ensemble runs showing a 20% chance for this solution 12-24 hrs ago. Precipitation will generally focus along the divide in northwest Montana under this scenario, with probabilities for >0.10" of precipitation peaking at 50-60% across Flathead County and the divide. The bottom line is those with plans across the higher elevations and in Glacier Park should monitor the forecast closely given the potential for widespread precipitation, much colder temperatures, and north- northeast winds making for adverse backcountry conditions for this time of year. Furthermore, choppy lake conditions across Flathead Lake would be a concern if this backdoor cold front solution comes to fruition. We will monitor this system closely in the coming days. && .AVIATION...GOES Satellite imagery shows a cumulus field along and north of the I-90 corridor associated with a passing disturbance along the US-Canadian border. Scattered showers are seen on regional radar imagery across Lincoln and Flathead County as of 10/1900Z. This activity will continue into the evening, with the risk of lightning from isolated thunderstorms focusing east of KGPI over Glacier National Park and the divide. Blustery westerly winds of 20-25kts will continue through 11/0200-0400Z for valley areas as this disturbance passes. Skies will clear overnight as high pressure begins to build into the region. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

827 FXUS65 KBOI 110258 AFDBOI Area Forecast Discussion National Weather Service Boise ID 858 PM MDT Thu Jul 10 2025 .DISCUSSION...Northwest flow remains over the area with increasing smoke aloft from area wildfires. Breezy northwest winds expected during the afternoons over the next several days. Temperatures will warm a few degrees each day into Sunday. No updates to the forecast. && .AVIATION...VFR. Localized smoke near wildfires in central ID and south-central OR. Surface winds: NW 5-15 kt with 15-20 kt gusts, gusts calming overnight. Winds aloft at 10kft MSL: NW 5-15 kt. KBOI...VFR. Surface winds W-NW 5-15 kt. Weekend Outlook...VFR. Localized smoke near wildfires. High density altitude due to hot temperatures, especially Sunday/Monday. Surface winds: NW 5-15 kt, with 15-25 kt gusts in the afternoons. && .PREV DISCUSSION... SHORT TERM...Tonight through Saturday night...Dry northwesterly flow will persist through the weekend, maintaining generally quiet weather across the region. Winds will remain light, with occasional afternoon gusts up to 25 mph in the lower valleys. Skies will stay mostly clear, though localized areas of smoke are possible due to new wildfire activity. A few additional fires have been detected on satellite today, and its likely that a few more will be seen this afternoon and evening. At this time, smoke impacts appear minimal. The northwesterly flow aloft should continue to steer smoke from larger fires in south-central Oregon away from the area. Temperatures will trend warmer through the weekendstarting near seasonal averages on Friday and rising to about 5 degrees above normal by Sunday. LONG TERM...Sunday through Thursday...Hot, dry, and breezy conditions are expected Sunday and Monday as strong high pressure dominates the southwest U.S. and influences the Intermountain West. A weak shortwave trough will approach from Canada late Monday and move south-southeast along the Northern Rockies by Tuesday. While the main bulk of mid-level moisture will remain east of the forecast area, latest guidance supports a 10-15% chance of thunderstorms farther west into central Idaho Tuesday afternoon and evening than previously expected. Surface winds will also increase with the trough passage and associated cold front, with gusts peaking around late afternoon. Max temperatures will lower slightly from Monday but are expected to remain a few degrees above normal. Thereafter, hot and mostly dry conditions are expected to return behind the trough. Models become somewhat disorganized toward the end of the week, but hint at the potential for showers/thunderstorms returning as southwest flow develops aloft. && .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 DISCUSSION...KA AVIATION.....JM SHORT TERM...JDS LONG TERM....SH

502 FXUS65 KLKN 102032 AFDLKN Area Forecast Discussion National Weather Service Elko NV 132 PM PDT Thu Jul 10 2025 .KEY MESSAGES... Updated at 129 PM PDT Thu Jul 10 2025 * Warming trend underway through at least Wednesday * Triple digit heat possible in the valleys of Northern and Central Nevada each afternoon Sunday through Wednesday * Moderate risk for heat-related illnesses each afternoon Sunday through Wednesday * Low chances for isolated thunderstorm activity Tuesday, Wednesday and Thursday afternoons across eastern Nevada && .DISCUSSION... (This evening through next Wednesday) Issued at 129 PM PDT Thu Jul 10 2025 Upper level ridge of high pressure will be the main weather maker for Nevada through at least Tuesday of next week. This ridge centered over the lower Colorado river valley, will build across the Great Basin region as it slow drifts west, which will trigger a warming trend that will see valley temperatures reach the triple digits for many beginning Sunday, and lasting through at least Wednesday afternoon. Highs will climb from the mid 80s to mid 90s this afternoon to reach the upper 90s to upper 100s by Monday afternoon. Overnight lows which would normally provide relief from the heat will also warm from the low 50s to low 60s Friday morning, into the upper 50s to low 70s by Tuesday morning. Will need to watch the temperature trends, as heat headlines my be needed for many for the end of the weekend and into the first half of next week as models show a moderate heat risk for the valley location along the I-80, US-6, and US-95 corridors as well as Alt US-93 in SE Elko county. Beginning Tuesday afternoon the GFS introduces a low 10% to 20% chance for some thunderstorms across the far eastern third of Nevada. The EC does lend minor support to this possibility with a few ensemble members, but is overall much less optimistic. The key factor will be if a upper level low develops over the Colorado river valley splitting the now weakening upper ridge in two. If this does develop there will be a path for monsoonal moisture to force its way into the Silver State next week, which will help cool temperatures a bit going into Next Wednesday and Thursday of next week. FORECAST CONFIDENCE & DEVIATIONS: There is high confidence in high pressure ridge building in over the the Great Basin trough the first half of next week leading much warmer temperatures and moderate heat risks. There is moderate for elevated fire weather conditions Sunday through Tuesday afternoons across NV due to warm temperatures and low humidity. Confidence is low for the possibility for thunderstorm development during the afternoon hours for Tuesday through Thursday of next week. && .AVIATION... (18Z TAFS) VFR conditions will prevail at all terminals through at least the next 24 hours, with gentle northwesterly breezes. AMD NOT SKED at KELY due to malfunctioning VIS sensor. && .FIRE WEATHER... A warming trend is expected this weekend. High temperatures across Northern and Central Nevada each afternoon Monday through Wednesday will be six to eight degrees above normal for this time of year. This will result in a moderate risk for heat-related illnesses. Elevated fire weather conditions are expected in Northeastern Elko County Monday afternoon into Monday evening due to northwest wind gusts near 25 mph and minimum relative humidity values as low as 13 percent. && .LKN Watches/Warnings/Advisories... None. && $$ DISCUSSION...98 AVIATION...87 FIRE WEATHER...87