ZSE Aviation Forecast Discussions

245 FXUS66 KSEW 231610 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 910 AM PDT Tue Jun 23 2026 .UPDATE... No changes made to the inherited forecast. The previous discussion remains below along with an updated aviation section. && .SYNOPSIS... Upper level ridge over the area today shifting east tonight. Thermally induced surface trough near the coast this morning will move inland this afternoon and east of the Cascades tonight. Increasing low level onshore flow Wednesday. First weather system in a couple of weeks approaching the coast Thursday. Front reaching the coast Friday morning moving east of the Cascades by Friday evening. Cool upper level low dropping down over the area Saturday. Low moving east Sunday with weak upper level ridge beginning to build offshore. Weak upper level trough moving through Monday. && .SHORT TERM /TODAY THROUGH THURSDAY/... Satellite imagery shows stratus right along the beaches central and south coast with a few high clouds moving through the area. Temperatures at 3 am/10z were in the mid 50s to lower 60s except mid to upper 60s in the Seattle area. Upper level ridge over the area today. Thermally induced surface trough near the coast will drift slowly east this afternoon maintaining low level offshore flow. 850 mb temperatures rising to plus 16C to 18C this afternoon. Highs warming into the 80s with the warmer locations like the Southwest Interior and Cascade Foothills reaching the lower 90s. Afternoon seabreeze kicking in along the central coast keeping highs in the 70s right along the beaches. Best chance for a record high today will be at Bellingham. Upper level ridge moving east of the Cascades tonight. Thermally induced surface trough also moving moving east of the Cascades tonight. Low level flow turning onshore along the coast with light low level flow over the interior. Lows tonight in the mid 50s to lower 60s. Record high minimum temperatures will be possible over the interior. Blend has high temperatures Wednesday just a degree or two lower than Tuesday. Thermally induced trough east of the Cascades with low level onshore flow to start the day increasing in the afternoon. Upper level ridge also east of the Cascades with temperatures aloft cooling. 850 mb temperatures in the plus 14C to 16C range in the afternoon. Winds in the lower levels also turning westerly Wednesday morning. Stratus remaining confined to the coastline but flow aloft turning west southwesterly pushing some high clouds cover through the area. All these variables add up to a cooler day Wednesday with highs 5 to 10 cooler than Tuesday, in the mid 70s to mid 80s for the interior. More cooling along the coast with stronger onshore flow. Highs on the coast in the mid 60s. Onshore flow increasing Wednesday night with surface high pressure building offshore ahead of an approaching weather system. High clouds continuing to move across the area with stratus moving inland late. Lows in the 50s. Front approaching Thursday. Rain out ahead of the system could reach the coast as early as the afternoon hours. Thickening cloud cover will keep highs in the 60s and lower 70s. Heat advisory remaining in effect for all the lowlands except the coastal beaches today. Cooling Wednesday will drop the inland coastal areas and the Northwest Interior out of the advisory. Heat advisory coming to an end for all locations Wednesday evening. Felton && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... Rain spreading inland Thursday night. Front reaching the coast Friday morning with the front east of the Cascades by late Friday afternoon. Rain turning to showers behind the front with breezy conditions. Post frontal air mass somewhat unstable for a chance of thunderstorms as well. Convergence zone setting up probably over Snohomish county in the afternoon and evening hours. Models are a little weaker with the southerly surface gradients which brings up the possibility the convergence zone could end up a little further south over Northern King County. Cool upper level low dropping down over the area Friday night into Saturday keeping showers in the forecast. Weak upper level ridge building offshore Sunday. Weak upper level trough moving down the backside of the ridge into Western Washington Monday for a chance of showers. High temperatures in the upper 50s to mid 60s Friday and Saturday and only in the 60s Sunday and Monday. There is a chance for record low maximum temperatures Friday and possibly Saturday. Felton && .AVIATION... Primarily VFR conditions are expected with passing high clouds through the forecast period. There is moderate confidence (50-60% chance) for IFR conditions to return at HQM Tuesday evening through Wednesday morning. Winds will generally be out of the north 5-10 knots for interior terminals and more variable in direction for the coastal terminals. KSEA...VFR expected through the TAF period. Northeast winds this morning 5-8 knots back to the northwest 8-10 knots in the late morning and early afternoon. Winds become more northerly 6-10 knots Tuesday night. A return of broader onshore flow on Wednesday will shift winds to the west-southwest sometime Wednesday morning between 10-14Z. && .MARINE... Thermally induced surface trough near the coast will drift slowly east this afternoon moving east of the Cascades tonight. Low level flow turning onshore along the coast with light low level flow over the interior. With the thermally induced trough east of the Cascades low level onshore flow to start the day Wednesday increasing in the afternoon and evening. A gale watch has been issued for the Central and Eastern Strait of Juan de fuca for Wednesday night. Onshore gradients easing Thursday. Frontal system moving through the waters Friday with possible small craft advisory winds with and just behind the front. Winds easing Saturday. Choppy seas developing over the outer coastal waters tonight with swell 7 to 9 feet with a 7 to 9 second period. The choppy seas will continue over the outer coastal waters through Wednesday night. Felton && .FIRE WEATHER... High pressure aloft combined with a thermally induced surface trough over the area will create elevated fire conditions today. In addition to the warm, dry, and conditionally unstable air mass, low level offshore flow will drop minimum relative humidity values into the twenties, and even the teens this afternoon. The upper level ridge and thermally induced trough moving east tonight but elevated fire weather concerns could linger into Wednesday. Fuels are approaching critical levels, but the main concern remains dry grasses or shrubs, or dead piles of fuels where brush fires may be able to start (as seen the last few days). Onshore flow will return with improved low level moisture Wednesday night and Thursday. Weather system moving into the area will bring a chance of wetting rains for the first time in a couple of weeks Thursday night and Friday. Cool weather will continue through the weekend. Felton && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Heat Advisory until 11 PM PDT this evening for Eastern Strait of Juan de Fuca-Foothills and Valleys of Thurston and Lewis Counties-Foothills and Valleys of the North Cascades-Foothills of the Western and Southern Olympic Peninsula-Island County-Lower Chehalis River Valley- Lowlands of Lewis and Southern Thurston Counties-Lowlands of Western Skagit and Northwestern Snohomish Counties- Lowlands of Western Whatcom County-Middle Chehalis River Valley-Northern Hood Canal-Olympia and Southern Puget Sound-Port Townsend Area-San Juan County-Southern Hood Canal-Willapa and Black Hills. Heat Advisory until 11 PM PDT Wednesday for City of Seattle- Downtown Everett / Marysville Area-Eastern Kitsap County- Eastside-Foothills and Valleys of Central King County- Foothills and Valleys of Pierce and Southern King Counties-Foothills and Valleys of Snohomish and Northern King Counties-Lowlands of Pierce and Southern King Counties-Shoreline / Lynnwood / South Everett Area. PZ...Gale Watch from Wednesday evening through late Wednesday night for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. Small Craft Advisory from 6 PM this evening to 6 AM PDT Thursday for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm. && $$

828 FXUS66 KPQR 231745 AAA AFDPQR Area Forecast Discussion National Weather Service Portland OR 1045 AM PDT Tue Jun 23 2026 Updated Aviation discussion .SYNOPSIS...Hot and dry conditions continue today, bringing widespread Moderate HeatRisk across all interior valleys. Increasing onshore flow tonight into Wednesday will bring high temperatures down a few degrees Wednesday afternoon. Cooler and wetter conditions arrive Thursday through Saturday, with a slight chance for thunderstorms Saturday afternoon. Drier conditions return Sunday-Monday, but we`ll still maintain slight chances for rain across the Coast Range and Cascades. && .DISCUSSION...Today through Monday...Satellite imagery as of early Tuesday morning depicts widespread marine stratus along the coast and mostly clear skies inland with a few high clouds. As daytime heating progresses today, we`ll see increased mixing and some stratus break-out by late morning. However, there is a 20-30% chance that stratus lingers throughout the day along the coast. Hot and dry conditions continue today with afternoon high temperatures forecast in the upper 80s to mid 90s, warmest along the I-5 corridor from Salem to the Cowlitz Valley. This will result in widespread Moderate HeatRisk across all interior valleys. This level of heat will affect those who are sensitive to heat, especially those without adequate cooling or hydration. The Heat Advisory remains in effect through 11 PM tonight along the I-5 corridor from Salem to the Cowlitz Valley, the Columbia River Gorge, and Upper Hood River Valley. Make sure to stay hydrated, wear light-colored and loose-fitted clothing, wear sun protection, taking frequent breaks from the heat, and limiting strenuous outdoor activities during the hottest part of the day. Onshore flow increases tonight into Wednesday as a weak trough passing through the region. The airmass is dry, so this trough is not expected to bring precipitation. Overnight lows in the low to mid 50s for most areas will provide overnight relief from the heat. An exception is the Portland/Vancouver Metro Area and Columbia River Gorge, where Wednesday morning between 60 to 65 degrees will provide limited relief from the heat. Because of urban heat island effects, the Portland/Vancouver Metro also has a 10-25% chance for Wednesday morning lows exceeding 65 degrees. Wednesday afternoon highs will still be very warm but a couple degrees cooler than today. Will also note that some high-resolution guidance is showing some very light precipitation over the Cascades this afternoon as the aforementioned trough moves through, however, there is low confidence it will actually reach the ground due to how dry the air is (aka it would fall as virga). A large-scale pattern change to cooler and wetter conditions remains on track Thursday into the weekend as ensemble guidance is in agreement with an upper-level trough approaching the Pacific Northwest. Most ensemble members have rainfall reaching the coast by late Thursday afternoon/evening and then spreading into the I-5 corridor by late Thursday night into Friday morning. We`ll remain in this cool and wet pattern through at least Saturday, but at least total rain amounts at this time appear beneficial and generally non-impactful. Chances for 48-hour rain amounts exceeding 0.50 inch from 5 AM Friday to 5 AM Sunday are around 60-80% for the coast and Coast Range, 50-70% along the I-5 corridor, and greater than 90% across the Cascades due to westerly flow bringing orographic enhancement. Will note that the westernmost parts of the Willamette Valley that are west of I-5 (including McMinnville and Corvallis) only have a 25-35% chance for exceeding 0.50 inch during this timeframe due to potential rainshadowing from the Coast Range. On Saturday, the upper-level trough will transition into a closed upper-level low and move directly over the Pacific Northwest. Temperatures will cool down aloft, increasing atmospheric instability and bringing CAPE values of 100-200 J/kg across the region late Saturday morning into the afternoon. This instability plus sufficient lift from the low will support a slight chance (15-20%) for thunderstorms across northwest Oregon and southwest Washington. LREF guidance also suggests 0-500 mb wind shear values around 25-35 kt with limited direction shear, so it appears that these thunderstorms will at least trend non- severe. Any passing thunderstorms may produce lightning, brief heavy rain, erratic winds, and/or small hail. Also can`t rule out a few cold air funnel clouds. By Sunday-Monday, the majority of ensemble members are showing the upper-level low shifting eastward, returning relatively drier conditions and a warm-up of a few degrees. Will still maintain precipitation chances across the Coast Range and Cascades as westerly flow continues to support orographic enhancement of precipitation, however, any additional rain amounts appear light. Westerly winds throughout this cool and wet pattern will be breeziest along the central Columbia River Gorge and across Upper Hood River Valley, with chances for isolated wind gusts exceeding 45 mph around 10-30% from Friday to the end of the weekend. -10 && .AVIATION...Southwest flow aloft ahead of a weak upper level trough that will move across the region this afternoon. Continued dry conditions with scattered to broken high clouds will maintain predominately VFR conditions across inland terminals. The main exception is the shallow marine stratus along the coast. As of 17z, satellite imagery shows the stratus pulling offshore from KAST, but continues to linger from KTMK southward with predominately IFR CIGs. Visibilities should continue to improve through the late morning and early afternoon hours. There remains moderate chances for improvement to VFR near KONP, however there is a 30-50% chance for marine stratus to persist through the afternoon. Chances for IFR/LIFR stratus returning to the coast increase again after 02-03z Wed. Light winds under 5 kt become WNW, increasing to 7-10 kt in the afternoon across any given terminal. In addition, high temperatures between 90 to 95 degrees are forecast across the Willamette Valley this afternoon. Be aware of high density altitude which may reduce aircraft performance. KPDX AND APPROACHES...VFR through the TAF period with SCT/BKN high clouds through this afternoon. Light and variable winds expected to become northwesterly, increasing to 7-10 kt in the afternoon/evening. /DH && .MARINE...High pressure will maintain north-northwesterly winds across the coastal waters through Wednesday. Winds generally expected to remain under 20 kt, but there is a 60-80% chance for isolated wind gusts up to 25 kt for the waters beyond 30 NM offshore. Given the low confidence for widespread and frequent wind gusts greater than 21 kt, decided against issuing Small Craft Advisories for the outer water zones beyond 10 NM offshore. Weakening high pressure will give way to a frontal system approaching the area on Thursday. Winds are expected to back west to southwesterly before the cold front pushes across the coastal waters late Thursday into Friday. Southwest winds are expected to be strongest for the waters north of Cape Foulweather and up to 10 NM offshore, but there is only around a 10-20% chance of small craft wind gusts exceeding 21 kt at any given hour through Friday morning. West to northwest winds will persist behind the front later Friday and into the weekend as weak low pressure lingers near Vancouver Island. High pressure gradually builds across the waters late weekend. Seas remain around 5 to 7 ft through Wednesday, subsiding to 4 to 5 ft on Thursday. -10/DH && .PQR WATCHES/WARNINGS/ADVISORIES... OR...Heat Advisory until 11 PM PDT this evening for ORZ108>115- 119>123. WA...Heat Advisory until 11 PM PDT this evening for WAZ204>210. PZ...None. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

783 FXUS66 KMFR 231741 AFDMFR Area Forecast Discussion National Weather Service Medford OR 1041 AM PDT Tue Jun 23 2026 .Updated AVIATION Discussion... && .AVIATION...23/18Z TAFs...The marine layer will remain well entrenched along the coast and at coastal sites today, maintaining IFR/LIFR conditions. There could be a brief period of improvement to VFR this afternoon, most likely between 22z-02z, but expect the quick return of LIFR/IFR conditions this evening, then persisting overnight. Inland areas will remain VFR through the TAF period with the typical increase in afternoon breezes. Cumulus buildups are also expected this afternoon over the higher terrain, with isolated thunderstorms possible south of the OR/CA border near the Mt Shasta/Medicine Lakes region. /BR-y && .PREV DISCUSSION... /Issued 424 AM PDT Tue Jun 23 2026/ DISCUSSION...Daytime highs are expected to remain 5 to 10 degrees above seasonal norms across northern California and southern Oregon today. This supports a Heat Advisory for the Rogue, Illinois, Shasta, Scott, and Klamath River valleys as well as valleys in eastern Curry County into this afternoon. A bit of passing instability may also help isolated afternoon and evening thunderstorms develop in Siskiyou County as well as northern Lake and Klamath counties. Conditions are not ideal, with CAPE values of 200-400 J/Kg and sparse midlevel moisture. SPC CAMs have higher confidence in the chances for Siskiyou County activity than anything developing east of the Cascades. The upper pattern starts to change on Wednesday. With the upper ridge departing to the east, a period of zonal flow will start a gradual cooling trend across the area. Another pocket of instability may bring some isolated thunderstorms develop on Wednesday afternoon and evening, this time with slightly better chances east of the Cascades. But like the Tuesday chances, the supporting conditions do not suggest abundant activity. A period of unimpactful active weather looks to start late Thursday, when a cold front looking to reach the Oregon coast. This front looks to bring light rainfall to the coast and the Cascades, with chances for drizzles over Douglas, Klamath, and Lake counties. Downsloping will likely keep the Rogue and Illinois valleys dry. This front may also bring gusty afternoon and evening winds east of the Cascades and over terrain in Siskiyou County. Long-term deterministic imagery is starting to inch towards agreeing on a low pressure system moving down from the northwest. ECMWF and GFS imagery both have the system swinging over Oregon, although the ECMWF expects the system to drop farther south and bring slightly more rainfall. In the end, rainfall will be measured in the hundreths or tenths of an inch for most places. Beyond the weekend, an upper trough looks to remain in place which will help to keep temperatures from warming too quickly, but signs of precipitation beyond the weekend are minimal. -TAD MARINE...Updated 800 PM PDT Monday, June 22, 2026...North winds will maintain strength through this evening. Isolated gale force gusts and very steep seas are possible south of Cape Blanco while steep seas persist across the northern outer waters. Northerly winds will continue Tuesday into Wednesday, resulting in Small Craft Advisory conditions for most of the waters through at least mid- week. Conditions briefly improve on Thursday. Then a cold front is likely to bring light rain and a modest increase in fresh west- northwest swell Thursday night into Saturday. && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Heat Advisory until 11 PM PDT this evening for ORZ024-026. CA...Heat Advisory until 11 PM PDT this evening for CAZ080>082. PACIFIC COASTAL WATERS...Small Craft Advisory until 8 PM PDT Thursday for PZZ356-370-376. && $$

883 FXUS66 KEKA 231052 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 352 AM PDT Tue Jun 23 2026 .SYNOPSIS...High pressure continues to build over the area, bringing warm and dry conditions. Isolated thunderstorms are possible in northern Trinity County Wednesday afternoon. Rain is possible for the North Coast Friday. && .KEY MESSAGES... - Warming trend for the interior will continue through Thursday. - Troughing to the north of the area on Wednesday could bring chances of interior thunderstorms. - Cooler temperatures, breezy winds, and a chance of rain is possible Friday. && .DISCUSSION...High pressure continues to build over Northwest California. Warm interior conditions with high temperatures for most valleys reaching the 90s. The warmest areas, along the Trinity and Klamath River Valleys, could see triple digits. This warming trend is likely to continue through Thursday. Coastal areas continue to see stratus continuing into the afternoon with only partial clearing. More clearing is possible Wednesday with breezier winds off the coast. Troughing to the north of the area today and Wednesday could bring additional chances of thunderstorms to northeast Trinity County. This afternoon, confidence is very low as both moisture and instability remain meager, but an isolated rain shower may be possible. Confidence is very slightly higher Wednesday with a modest increase in moisture, but still chances remain at around 10%. Ensembles are showing high confidence in a upper-level trough moving through the area late Friday. Rain chances have increased for the North Coast with NBM showing around a 50% chance for measurable rain for Humboldt and Del Norte Counties. Wetting rain (over 0.1") is around 50% in coastal Del Norte and 25% over coastal Humboldt. Outside a few sprinkles, the rest of the area is likely to remain dry; but increased cloud cover and breezy winds will drop high temperatures 15 to 20 degrees in the interior. Especially breezy westerly wind in Lake and southern Mendocino Friday are highly likely evening behind the frontal passage. NBM shows over 70% chance for gusts over 30 mph for much of Lake County, while the higher terrain can see gusts over 40 mph. This will need to be watched for a potential fire weather threat. Otherwise, chilly nights, especially for June, are likely behind this frontal passage with mid to high 30s possible for the coldest interior valleys. JB && .AVIATION...LIFR ceilings will envelope the coast through late morning/early afternoon. There could be periods of fog this morning. Some lifting to IFR and brief scattering is possible this afternoon/evening. Otherwise, LIFR ceilings and visibilities are possible again tonight for the coast. Inland areas, aside from a few near-coast river valleys, are likely to remain VFR. There is more of a chance for lifting and scattering of coastal stratus by mid week. && .MARINE...Northerly winds continue to diminish today, but could still be breezy in the lee of Cape Mendocino. Stronger northerly winds with near-gale to gale force gusts briefly return Wednesday. Winds ease again late week as a general troughing pattern sets up. Stronger northerly winds return this weekend. Seas this week remain dominated by wind waves and small long period northwest and southerly swells. JB && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 9 AM PDT this morning for PZZ470- 475. && $$ 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

731 FXUS66 KMTR 231750 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1050 AM PDT Tue Jun 23 2026 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 1215 AM PDT Tue Jun 23 2026 - Hazardous beach conditions along the Pacific Coast through Wednesday - Warming trend continues, peaking midweek, with Minor HeatRisk expected - An upper trough settles over the West Coast by late week, bringing cooler temperatures and breezy to gusty winds && .SHORT TERM... Updated at 1215 AM PDT Tue Jun 23 2026 (Today through Wednesday) The marine layer is roughly 1000 to 1500 ft with stratus building back inland early this morning, although slightly less inland push than yesterday morning. The marine layer will continue to slowly compress through the short term with a slow reduction in stratus and a warming and dry trend through midweek. The more compressed marine layer will allow patchy fog to develop along the coast and in wind-sheltered valleys this morning and again tonight/Wednesday morning. While a warming trend is expected through Wednesday, have lowered highs temps a couple of degrees as the overall ridging pattern is trending weaker. As a result, the threat of Moderate HeatRisk conditions for portions of the South and East Bay looks to have ended Highs will climb into the 80s for inland areas, while far interior areas will reach the 90s. Continued cool along with coast with highs in the upper 50s to lower 60s, with 70s for near- coast areas. We continue to highlight a long-period southerly swell that will bring a risk for sneaker waves and strong rip currents, with a Beach Hazards Statement out through Wednesday. If heading to the coast, stay back from the beach, and away from jetties, piers, beachside rocks, and other infrastructure near the water. Never turn your back to the ocean! For more information, see the BEACHES section. && .LONG TERM... Updated at 1215 AM PDT Tue Jun 23 2026 (Wednesday night through next Monday) An upper-level trough will approach the West Coast by Thursday. Temperatures will still be similar to Wednesday, with a few spots seeing their afternoon highs slightly lower than Wednesday, mainly south of the Bay Area. The cooling trend will become more pronounced Friday into Saturday as upper-level troughing deepens over the region, leading to a resurgence of the marine layer and breezy to gusty winds. Temps will be the coolest on Saturday with highs generally in the 60s and 70s. Patchy drizzle will could also develop along the coast. Onshore winds will increase, peaking Friday and Saturday with a frontal passage, with gusts 30 to 40+ mph across ridgelines and through gaps and passes. A slight warming trend is still favored for Sunday into early next week, but overall confidence remains low as there is quite a large spread in model guidance in regards to the progression of the upper trough to the east and ridging trying to creep back in from the eastern Pacific. && .AVIATION... (18Z TAFS) Issued at 1040 AM PDT Tue Jun 23 2026 Marine stratus will continue to erode toward the coast and nearly all terminals should be VFR within the next few hours, the exception being KHAF where low cigs will likely persist through the afternoon. Typical diurnal wind pattern expected this afternoon, easing through the evening. Similar cloud bases returning to most areas this evening through Wednesday morning. Vicinity of SFO...VFR conditions will prevail through the afternoon with winds increasing out of the NW/W. A few gusts to near 25 knots will be possible. MVFR conditions forecast to return by 04z Wed as marine stratus moves back into the area, becoming IFR shortly thereafter. Conditions should improve by mid/late morning, with a return to VFR conditions around 18z. SFO Bridge Approach...Similar to SFO. Increased chance of BKN cigs to linger in the afternoon hours. Vicinity of SJC and OAK...Marine stratus will likely persist for another couple hours at OAK. Otherwise, VFR conditions will prevail through the afternoon with a typical diurnal increase in winds to around 15 knots. Winds ease and MVFR clouds roll back in between 04z and 08z. OAK likely to see IFR conditions for much of the 06-16z Wed timeframe. Expect improving conditions after 15z with a return to VFR conditions during the late morning to early afternoon. Monterey Bay Terminals...Stratus has already cleared at SNS and is forecast to clear in the next 2-3 hours at MRY. There is some potential that NW flow aloft will result in only intermittent scattering to MRY, so will need to keep an eye on both satellite and surface observation trends. MVFR cigs returning after 01z Wed, becoming IFR shortly thereafter. Typical diurnal W/NW winds 5-15 kts. && .MARINE... (Today through Sunday) Issued at 1040 AM PDT Tue Jun 23 2026 Gentle to moderate winds persist through midweek with generally moderate seas. Fresh to strong breezes are forecast to resume over the coastal waters late in the week, resulting in rough seas across the coastal waters. Long period southwest swell will persist through the extended forecast. && .BEACHES... Updated at 1215 AM PDT Tue Jun 22 2026 Long period southerly swell at around 14 to 16 seconds will increase to 17 to 19 seconds by the middle of the week as energetic storms in the Southern Hemisphere continue to affect the California coast, especially for south and southwest facing beaches. Hazardous beach conditions are advertised, specifically for moderate to steeply sloped beaches along the Pacific Coast of the North Bay, San Mateo, Santa Cruz counties. A Beach Hazards Statement for Pacific Coast beaches continues through Wednesday afternoon. Be sure to check beach conditions before you head out. Sneaker waves will run up the beach much farther than other waves, potentially catching beachgoers by surprise and resulting in people being swept into the water. Rip currents are strong enough to pull the strongest swimmers away from shore. Swim near a lifeguard if possible. Stay back from the beach, and away from jetties, piers, beachside rocks, and other infrastructure near the water. Never turn your back to the ocean! && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement through Wednesday afternoon for CAZ006- 505-509-529-530. PZ...None. && $$ SHORT TERM...Slagle LONG TERM....Slagle AVIATION...Manning MARINE...Manning 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

575 FXUS66 KOTX 231752 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 1052 AM PDT Tue Jun 23 2026 .KEY MESSAGES... - Warm temperatures continue through Wednesday. Wednesday will be our warmest day with highs in the upper 80s to mid 90s. - 20 to 30 percent chance of showers and thunderstorms over the Cascades and northern mountains Wednesday afternoon and evening. - Weather changes arrive late week with much cooler temperatures, gusty winds, and rain showers. && .SYNOPSIS... Warm and dry conditions will persist through Wednesday with the exception of shower and thunderstorms chances over the Cascades and northern mountains Wednesday afternoon. The pattern shifts toward the end of the week and into the weekend as a weather system delivers much cooler temperatures, gusty winds, and rain showers for much of the region. && .DISCUSSION... Tuesday through Thursday: A ridge axis shifting east over the region will bring mostly warm and dry conditions through Thursday. The exception will be over the Cascades and Northern Mountains in the afternoon and evening hours Tuesday and Wednesday, where steepening lapse rates and a weak mid level disturbance will bring chances for showers and thunderstorms. For Tuesday afternoon and evening, shower and thunderstorm chances are hovering around 10 percent. By Wednesday afternoon and evening, these chances increase to 20 to 30 percent. Heading into Thursday, the area of elevated instability and shower activity will shift eastward into the ID Panhandle. Dry air near the surface will likely result in most of the precipitation outside of rain cores evaporating before it reaches the ground. Thus, any lightning strikes in areas of dry fuels may result in new fire starts. Gusty outflow winds from thunderstorms are also a concern. On Thursday, flow shifts out of the southwest ahead of an incoming trough. Friday through Monday: There is high confidence in a significant drop in temperatures as a robust upper level trough drops into the region from the Gulf of Alaska. Ensemble clusters are now in good agreement on the trough lingering over the Northwest through the weekend, keeping precipitation chances over the region for several days. The initial front associated with the trough swings through the region early Friday, bringing a 70-90 percent chance of rain showers over the eastern third of Washington, the Cascade crest, and the ID Panhandle with a 20-40 percent chance of rain showers across Central Washington. In addition to shower chances, there will be a 15-30 percent chance of thunderstorms across most of Eastern WA and the ID Panhandle Friday and across the northern mountains on Saturday. With any dramatic drop in temperatures comes breezy winds, and this event will not be an exception. Expect a prolonged period of breezy winds ramping up on Wednesday and lasting through the weekend. The current forecasts has west/southwest winds with gusts of 20-35 mph during this time period. /Fewkes && .AVIATION... 18Z TAFs: VFR conditions are expected across all terminals throughout the TAF period. Light winds (less than 10 kts) will prevail across the region with a few passing high clouds through the day on Wednesday. An unstable atmosphere will lead to moderate cumulus development over the northern mountains this afternoon, with a 15% chance of thunderstorms between 23z-03z over the North Cascades. Any storms that develop are not expected to impact any of the regional airports. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in VFR conditions at all terminals through the forecast period. JW ----------------------- 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 86 55 89 57 85 53 / 0 0 0 10 0 10 Coeur d`Alene 85 57 88 59 84 55 / 0 0 0 10 0 10 Pullman 84 52 86 55 82 49 / 0 0 0 0 0 20 Lewiston 91 60 93 62 90 58 / 0 0 0 0 0 20 Colville 88 53 90 54 86 51 / 0 0 0 20 10 10 Sandpoint 84 60 87 60 83 56 / 0 0 0 20 10 10 Kellogg 84 55 86 56 82 54 / 0 0 0 10 0 10 Moses Lake 91 57 94 59 89 54 / 0 0 0 0 0 20 Wenatchee 90 64 91 65 86 60 / 0 0 10 20 0 30 Omak 91 61 93 58 89 56 / 0 0 10 20 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

043 FXUS66 KPDT 231704 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1004 AM PDT Tue Jun 23 2026 .KEY MESSAGES... - Moderate HeatRisk conditions continue through Wednesday thanks to an overhead ridge. - Breezy winds developing Thursday with lingering dry air will bring elevated/critical fire weather conditions. - Wetter pattern by the later part of the week with widespread showers region wide with isolated thunderstorms developing across the Blues/Eastern Mountains. && .DISCUSSION... Satellite and radar imagery continue to show dry and clear conditions thanks to overhead ridge situated over the Pacific Northwest. Guidance is in great agreement that the ridge will continue to advance through the region, promoting the warming trend to continue through at least Wednesday (70-90% chance). High temperatures will continue to climb into the low to high 90s in the lower elevated areas with dry air continue to linger in the region. HeatRisk will continue to show widespread moderate risk through Wednesday, mainly confided to the lower elevations that include the Columbia Basin, Eastern Gorge of WA & OR, Kittitas/Yakima Valley, and Central OR. By Thursday, the upper level ridge will continue to move east and a mid-level shortwave will slide into the region promoting breezy winds of 20-30 mph gusts to develop. With breezy winds and dry air still lingering despite the shortwave approaching, elevated fire weather conditions will develop across the Oregon Columbia Basin (OR691) (70-80% confidence), as well as across Kittitas/Yakima Valley Region (WA690), Columbia Basin of Washington (WA691), and Central Oregon (OR700) (70-80% confidence). With the passing shortwave, a trough will move into the region by Friday (60-80% confidence) bringing unsettled weather across the region that include breezy winds, widespread rain showers, and isolated thunderstorms across the mountain regions (15-30% chance for the thunderstorms). Temperatures will have a significant cooling trend with the passage of the cold front, dropping high temperatures to the mid to high 70s across the lower elevation (60-80% confidence). The good news on the fire weather side, is that the sufficient moisture transportation will relief us of the dry air. Current NBM guidance advertises minimum relative humidities jumping from the 10-20% range up to 30-50% with overnight recoveries improving to the `good` to `excellent` range by late Thursday night/early Friday morning (70-90% confidence). && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... VFR conditions will persist through the period with light winds less than 12 knots for all TAF sites until 22-23Z. After 22-23Z, RDM/BDN will see an increase in winds of 10-13G17-21KT before settling to 10kts after 01-04Z respectively. No CIG or VIS issues expected. && .Preliminary Point Temps/PoPs... PDT 91 56 92 59 / 0 0 0 0 ALW 92 61 93 64 / 0 0 0 0 PSC 94 59 96 61 / 0 0 0 0 YKM 92 61 95 59 / 0 0 10 0 HRI 93 58 95 63 / 0 0 0 0 ELN 89 60 91 59 / 0 0 20 10 RDM 89 52 88 48 / 0 0 10 10 LGD 90 54 89 54 / 0 10 0 0 GCD 94 52 91 52 / 0 0 10 10 DLS 95 64 94 62 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...Heat Advisory until 11 PM PDT this evening for WAZ024. OR...Heat Advisory until 11 PM PDT this evening for ORZ041. Red Flag Warning until 8 PM PDT this evening for ORZ691. && $$ DISCUSSION...95 AVIATION...95

422 FXUS65 KREV 230906 AFDREV Area Forecast Discussion National Weather Service Reno NV 206 AM PDT Tue Jun 23 2026 .KEY MESSAGES... * Above average temperatures, and widespread moderate HeatRisk are expected through Thursday for western NV, with typical afternoon breezes prevailing. * Increasing fire weather concerns for Friday & Saturday due to strong and gusty winds combining with low humidity. * Much cooler over the weekend with light showers possible. Near freezing low temperatures possible for Sierra valleys. && .DISCUSSION... Highs this afternoon will heat into the upper 90s for W.Nevada valleys with Sierra valleys reaching the mid-80s. Expect widespread moderate HeatRisk across much of W.Nevada, along with isolated areas of Major HeatRisk in Basin and Range valleys where temperatures could touch 100 degrees. Skies will remain mostly clear, aside from some afternoon cumulus development which could support a 10-15% chance of a few pop-up showers and even an isolated thunderstorm across Mineral County this afternoon. Highs will gradually cool by 2-3 degrees daily through Thursday, followed by a more significant drop over the weekend as a series of potent cold fronts moves through the region. Typical afternoon zephyr winds will continue through Wednesday, with gusts increasing to 20-25 mph by late afternoon and early evening. Winds will continue to intensify Friday-Saturday, with a 40-50% chance of gusts reaching 40 mph, mainly from along Highway 395 eastward into the Nevada Basin and Range. The main frontal passage arrives Saturday, which is expected to increase sustained winds near 20-30 mph in addition to gusts of 30-40 mph. Critical fire weather conditions are a growing concern for Friday and Saturday. See the Fire Discussion below for additional details. In addition to fire weather concerns, these winds could disrupt outdoor recreation, create hazardous boating conditions, and impact road and aviation travel. High profile vehicles could be impacted by strong crosswinds, and blowing dust may reduce visibility in areas downwind of desert sinks. Precipitation chances remains limited with this front with 20-50% chance of light showers Friday/Saturday with only a 10-30% chance of wetting rains (0.1") northward of Susanville-Gerlach to the Oregon border. In addition, isolated thunderstorm chances of 10-15% are possible for the Surprise Valley and far N.Washoe county. A significant cool down is expected in the wake of the cold front as high temperatures fall to 10-20 degrees below late June averages. This will translate to highs in the mid and upper 70s for W.Nevada with 60s for the Sierra. Sierra valleys could see 40-50% odds of overnight lows falling below freezing. Even Carson Valley communities could see a 10-15% chance hitting the freezing. Fuentes && .AVIATION... VFR conditions will prevail this afternoon with typical westerly afternoon/evening gusts of 20-25 knots. A few buildups over the high terrain each afternoon, but chances for showers and storms are less than 5% outside of 10-15% chances this afternoon at KHTH. The warmest temperatures of the week are expected this afternoon with highs reaching the upper 90s for W.Nevada terminals which may yield density altitude impacts today. Fuentes && .FIRE WEATHER... Hot and dry conditions will persist through Thursday. Today is expected to be the hottest day, with highs reaching the upper 90s in W.Nevada valleys. Afternoon relative humidity will drop into the teens and single digits, with poor overnight recovery below 30% across W.Nevada mid-slopes and Basin and Range valleys. The primary fire weather concern is a critical pattern developing this weekend from a series of strong cold fronts expected to move through on Friday and Saturday. Confidence is increasing for critical fire weather conditions due to the strong winds and low humidity across portions of W.Nevada. Winds will remain typical through Wednesday, with afternoon westerly gusts around 20-25 mph. Gusts increase to 25-30 mph on Thursday, then strengthen further Friday and Saturday as the front moves through. Isolated critical conditions may develop as early as Thursday afternoon, but the greatest concern is Friday and Saturday, especially from US-395 eastward where dry conditions could combine with gusts of 30-40+ mph. In addition, Saturdays winds are showing signals for a strong sustained wind component of up to 20-30 mph as the front sweeps through the region. Any new ignitions or lightning holdovers could rapidly spread with these expected wind speeds. Fuentes && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

505 FXUS66 KSTO 231846 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1146 AM PDT Tue Jun 23 2026 .KEY MESSAGES... - Warm and dry this week with minor to moderate HeatRisk. Breezy onshore winds each day will provide relief for the Delta/Sacramento Area. - A weather system moving across the Pacific NW into the Great Basin will bring breezy onshore winds Friday into Saturday with a few showers north, followed by the potential for a north wind event Sunday into Monday. && .DISCUSSION... Warm and dry conditions expected today into Wednesday as ridging remains in control of the large scale pattern over the area. Above normal temperatures will rule with 90s to low 100s across the Valley. This will lead to minor to moderate HeatRisk but no concerns for heat headlines. Delta Breeze will continue to bring evening relief thru the Delta into the Sacramento area. Min RHs will be in the teens to low 20s but wind will remain below RFW criteria. Wednesday afternoon will see a nonzero chance of a mountain shower across the northern Shasta County border but current models keep any developed system north of our area, tracking eastward. Thursday is a transition day as cooling trend begins and continues into the weekend. A deep trough from the Gulf of Alaska will slowly dig into the Pacific Northwest Friday into the weekend and gradually move east into the Great Basin. This will serve to increase onshore flow for our area Friday into Saturday with breezy southerly winds across the area. This will bring a bit of moisture with it with the chance for a few showers across far northern portions of the area and southern Cascades. At this time, does not look like a big signal for convective activity but will keep an eye on trends. Current precipitation depict a glancing blow for our area over the mountains Friday afternoon into Saturday with still minimal precipitation impacts. As trough departs, pressure gradient strengthens, leading to the potential for a north wind event Sunday into Monday. Still some uncertainty in ensemble solutions with timing and strength of the trough but will need to monitor for the need for any fire weather headlines as we get closer to the weekend. && .AVIATION... VFR conditions are expected to continue through the TAF period. Winds 6 to 12 kts in the Valley into 06z Wednesday before becoming light and variable overnight outside of winds through the Delta to the Sacramento sites which will gusts up to 15-25 kts until 12z Wednesday but linger in the Delta. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

346 FXUS65 KMSO 231002 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 402 AM MDT Tue Jun 23 2026 .DISCUSSION... KEY MESSAGES: - Warming the next couple of days, but potential for isolated to scattered showers. - Cooler and wet conditions expected this coming weekend. A low amplitude ridge will be over the region the next couple of days causing a warming trend, but the subtle disturbances passing through the ridge will cause cloud cover along with isolated to scattered showers. This afternoon the best potential for shower activity will be along the Continental Divide around Glacier National Park. Then tonight a feature is expected to pass across north central Idaho into west central Montana. Then on Thursday a pulse of energy pushes across the region ahead of the strong low pressure system. This disturbance will cause scattered showers and thunderstorms. The cold front is still on track to move across the Northern Rockies on Friday with the large low pressure system settling over the Pacific Northwest and Northern Rockies this weekend. All long term models are in agreement of this pattern change for the weekend, but the path of the closed low across the region this weekend into first part of next week is still a little uncertain. The path of the low will have a significant impact on what areas will receive the heaviest precipitation amounts. The current consensus of the models have the heaviest precipitation across Idaho and Lemhi county into southwest Montana with amounts ranging from 0.75 to 1.5 inches of rain Saturday into Sunday. Then the heaviest precipitation shifts up into northwest Montana Sunday into Monday as low shifts to the east. Glacier National Park is still expected to receive 1 to 2 inches of moisture. Snow levels will drop to around 7000 feet Sunday and Monday mornings bring accumulating snow to the higher terrain. Sunday appears to be the coldest day as afternoon readings will be around 20 degrees below seasonal averages. && .AVIATION...Clear skies this morning across the region with most terminals experience light and variable winds. The exception being KMSO where a drainage wind is causing gusty easterly winds. This wind will diminish during the late morning hours. A few showers are expected to develop across northwest Montana this afternoon, especially near Glacier National Park. KGPI has a low probability of being impacted by these storms. The winds will become westerly this afternoon at all terminals. Tonight a weak disturbance will pass across north central Idaho into west central Montana bringing increased clouds with slight chance of shower activity. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

358 FXUS65 KBOI 231803 AFDBOI Area Forecast Discussion National Weather Service Boise ID 1203 PM MDT Tue Jun 23 2026 .UPDATE...Updated aviation discussion. && .KEY MESSAGES... - Temperatures around 5 to 10 degrees above normal through Thursday. - Slight chance of afternoon thunderstorms Tuesday and Wednesday south along the NV border, but outflow winds may reach southern Malheur, Harney, Owyhee and Twin Falls counties. - Major change beginning Friday with arrival of a cold front and showers, followed by gusty winds, showers and chance of thunderstorms through Sunday. Snow possible as low as 6500-7000 feet MSL Saturday night and Sunday. && .SHORT TERM /Through Thursday Night/... Issued 428 AM MDT TUE JUN 23 2026 An upper level ridge will continue to expand over the region with mid level moisture moving over the area through the short term. Temperatures will remain around 5 to 10 degrees above normal. A pair of disorganized shortwaves will move across the Pacific NW bringing increased clouds, isolated showers and thunderstorms. The first wave moves across the Pacific NW late this afternoon, with increasing high clouds and isolated showers and thunderstorms in eastern OR along the NV border this afternoon. The system will move over Idaho overnight, bringing a chance of sprinkles overnight into Wednesday morning. Isolated showers linger near the NV/ID border on Wednesday morning, generally south of Twin Falls. Similar conditions expected Wednesday with more shower coverage along the NV border and increasing clouds during the afternoon. The main shortwave tracks over the region overnight Wednesday into Thursday morning with light rain showers and a slight chance of thunderstorms. Clouds clear out midday Thursday before increasing clouds late from the next system moving in from the Gulf of Alaska. && .LONG TERM /Friday through Tuesday/... Issued 428 AM MDT TUE JUN 23 2026 An upper level trough from the Gulf of Alaska will move southeast into the Pacific NW. A cold front moves through southeast OR and southwest ID on Friday with cooler and unsettled conditions through Saturday and Sunday. Significant precipitation possible with this system if the trough moves overhead. Still significant model differences though in the positioning of this trough, but wetting rains possible Saturday and Sunday with temperatures as much as 10-20 degrees below normal. Light snow possible on the peaks above 7000 feet Sunday morning. Conditions dry out with breezy conditions on Monday and Tuesday as the system moves northeast into Manitoba. This system will keep temperatures below normal under cool northwest flow aloft. && .AVIATION /18Z Tuesday through Wednesday/... Issued 1129 AM MDT TUE JUN 23 2026 VFR and patchy smoke over Treasure Valley areas. High density altitude during the afternoon due to heat. Isolated showers/thunderstorms near OR/NV border in the late afternoon through evening, which may produce gusty outflows up to 35 kt over SE OR. Surface winds: variable or E-SE 5-15 kt becoming NW-NE 5-15 kt in the afternoon. Winds aloft at 10kft MSL: W-NW 10-20 kt, then S- SW 5-15 kt in the afternoon. KBOI...VFR. High density altitude during afternoon from heat. Surface winds: SE 5-10 kt becoming NW 5-15 kt in the afternoon after 20Z. && .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.....JY SHORT TERM...KA LONG TERM....KA

098 FXUS65 KLKN 230904 AFDLKN Area Forecast Discussion National Weather Service Elko NV 204 AM PDT Tue Jun 23 2026 .KEY MESSAGES... * Near record heat today with highs in the mid to upper 90s * Moderate risk for heat-related illnesses in the valleys of Northern and Central Nevada this afternoon * Scattered showers and isolated thunderstorms Wednesday over mainly Elko and White Pine counties * Elevated fire weather conditions Thursday through Sunday due to gusty winds and low humidity, strongest winds on Saturday * Much cooler this weekend with lows in the mid 30s to low 40s && .DISCUSSION... (Tonight through next Monday) WEATHER PATTERN OVERVIEW: High pressure continues to build across the Great Basin region today, with afternoon high temperatures reaching mid to upper 90s. Mostly sunny this afternoon for most of the CWA, however far northern Elko County should see partly to mostly cloudy skies by the late afternoon hours with a 5 to 10 percent chance of thunderstorms. A couple degrees cooler on Wednesday with broad trough energy approaching from the west. Just enough instability and mid-level moisture across mainly the eastern half of the CWA Wednesday afternoon and early evening to produce cumulus build-ups, with a 10 to 15 percent chance of thunderstorms across Elko and White Pine counties. An upper level low over the Gulf of Alaska mid-week is expected to reach western WA by Friday evening before centering over the PacNW Saturday afternoon. The approaching system will result in a cooling trend this week, with highs Sunday afternoon only in the 60s to low 70s, and overnight lows this weekend dipping into the 30s to low 40s. Additionally, the approaching low will produce gusty afternoon and evening winds across the region Thursday through Sunday. Strongest winds are expected on Saturday which may reach wind advisory levels with sustained west to southwest winds of 20 to 30 mph and gusts of 35 to 50 mph. FORECAST CONFIDENCE & DEVIATIONS: High confidence in well above normal temperatures this afternoon. Low confidence in thunderstorm chances this afternoon for NE Elko County. High confidence in temperatures trending cooler Wednesday through Sunday. Low to moderate confidence in isolated thunderstorms across portions of Elko and White Pine Counties Wednesday afternoon and early evening. Moderate to high confidence in gusty winds later this week. No deviations from the NBM model output. && .AVIATION...VFR conditions at all terminal today and tonight. Well above normal temperatures this afternoon with highs in the mid to upper 90s under mostly sunny skies. Wind gusts this afternoon and early evening are expected to reach 20 to 25 knots at all TAF terminals except KENV where lighter winds are expected. && .FIRE WEATHER...Hot this afternoon with highs in the mid to upper 90s. There is a 5-10 percent chance of dry thunderstorm this afternoon and early evening over mainly northern portions of zones 469 and 470 where skies will become mostly cloudy. Otherwise, mostly sunny today with west to southwest winds of 10 to 20 mph gusting up to 25 mph in the afternoon and early evening hours. Best chances (10-15%) for thunderstorms this week will be Wednesday afternoon across mainly zones 469 470 and 425, likely leaning dry. Elevated fire weather conditions each afternoon and evening Thursday through Sunday due to gusty winds and low humidities. Strongest winds are expected on Saturday. && .LKN Watches/Warnings/Advisories...None. && $$ DISCUSSION...96 AVIATION...96 FIRE WEATHER...96