454 FXUS66 KSEW 051622 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 922 AM PDT Tue May 5 2026 .SYNOPSIS... An upper level ridge will remain over western Washington through Thursday, keeping temperatures above normal. Onshore flow will continue throughout the week, bringing rounds of morning stratus to the area. A dissipating frontal system will move into the region Friday into Saturday, bringing the next chance of some showers. Another ridge will build into the region Saturday afternoon into Sunday, but looks to weaken early next week. && .SHORT TERM /TODAY THROUGH THURSDAY/... No public updates have been made this morning. The rest of the previous discussion will follow with an update to the aviation sections. Expect stratus to continue to expand across Puget Sound through the morning hours for some morning cloud cover across the area. Stratus will then scatter and retreat back to the coast by the late morning/early afternoon hours. Temperatures as a result will be a few degrees cooler than yesterday`s, but will still be above normal, topping out in the mid 70s across much of the interior. Minor HeatRisk will continue across the interior as a result. The coast will stay cooler under the marine layer, with temperatures expected to top out in the 60s. High pressure will remain in control both Wednesday and Thursday for continued warm and dry conditions across western Washington. Onshore flow will also continue, bringing additional rounds of morning stratus to the area. At this time, onshore flow looks to increase and be the strongest Wednesday night into Thursday, which will allow for cloud cover on Thursday to stick around a bit longer. Temperatures will still trend above normal, nevertheless, with afternoon highs expected to be in the upper 60s to low 70s. Minor HeatRisk will continue across portions of the interior, but will gradually decrease in extent both Wednesday and Thursday. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... A weak, dissipating front will approach the area on Friday, bringing the next chance of showers. Overall amounts look to remain rather light, with some areas not even expected to see any precipitation. Latest probabilities still indicate less than 10 percent chance of the area exceeding 0.10" of rain. Temperatures will cool on Friday and will only top out in the low to mid 60s. High pressure will then build back into the Pacific Northwest in the wake of the front for another period of dry weather heading into early next week. Temperatures will warm a few degrees each day, topping out in the mid 70s for highs by Sunday. Minor HeatRisk will return to areas across the interior, though the coast will remain cooler, with temperatures only expected to be in the 60s. 14 && .AVIATION... An upper ridge axis centered offshore today will shift inland tonight with northerly flow aloft becoming west to northwesterly. Moderate onshore flow continues near the surface. The marine layer will extend into the interior lowlands this morning with widespread IFR or low MVFR ceilings. The stratus will burn back to near the immediate coastline after 18Z with VFR expected across most of the interior from 20Z into this evening. The stratus will migrate inland again tonight with widespread low MVFR or IFR ceilings expected for most terminals again Wednesday morning. KSEA... Solid marine stratus clouds with cigs of 010-020 will persist through the rest of the morning. A breakout back to VFR cigs won`t occur until after 19Z to 20Z. Southwesterly flow at 5-7 kts will continue throughout the period. Continued onshore flow will bring back another round of stratus clouds on Wednesday morning. 21/27 && .MARINE... Varying degrees of onshore flow will persist through the week as a surface ridge remains anchored offshore with lower pressure inland. A weak system passing north of the area late Wednesday will enhance the onshore flow. This will lead to possible westerly gales in the central and east strait Wednesday evening as well as gusty northwest winds and steep seas for the outer coastal waters. 27 && .HYDROLOGY... No river flooding is expected. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory from 4 PM this afternoon to 3 AM PDT Wednesday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca. Gale Watch from Wednesday afternoon through late Wednesday night for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca. && $$

310 FXUS66 KPQR 051538 AAB AFDPQR Area Forecast Discussion...UPDATED National Weather Service Portland OR 838 AM PDT Tue May 5 2026 Updated aviation discussion. && .SYNOPSIS...High pressure over the Northeastern Pacific will continue to support dry and warmer-than-normal conditions across the region through much of the week. Onshore flow will maintain marine cloud cover and drizzle along the coast, and nightly pushes inland which will clear through the day. Chances increase for cooler and wetter weather Friday into Saturday, before becoming warm and dry again late this weekend. && .DISCUSSION...Now through Monday...A consistent weather pattern will see similar conditions persist across the region through at least midweek. Broad upper-level ridging which spans the Northeastern Pacific and western CONUS will continue to favor largely dry weather and above-normal temperatures. Afternoon highs will remain in the upper 50s to upper 60s along the coast and in higher terrain, and in the upper 60s to upper 70s within inland valleys through Thursday. A low marine cloud deck will vary diurnally, with inland pushes each night bringing mist or drizzle to the coast and increasingly overcast skies inland, followed by a daytime withdrawal allowing skies to trend clearer. The timing and speed of the morning cloud burn-off will modulate afternoon highs; temperatures will likely rise higher than expectations if clearing occurs early, while a more persistent morning overcast will limit how high temperatures can reach that afternoon. Regardless, seasonably warm temperatures are only expected to result in heat impacts for those extremely sensitive to heat. Consensus remains fairly high that an upper-level shortwave will ride over top of the ridge, bringing more seasonable temperatures and low to moderate chances for rain Friday into Saturday. Those chances remain only 25-45% at the highest along the coast and in higher terrain, and increasing to the north from around 10% near Eugene to 20% near Kelso/Longview along the I-5 corridor. Rain chances quickly drop below 5% east of the Cascade crest including the Hood River Valley and Central Columbia Gorge. The majority of ensemble members favor rain beginning at the coast sometime Friday afternoon, although any time from Friday morning to late Friday night remains possible, then moving inland within a few hours. Potential rainfall amounts remain very light, less than a tenth of an inch. By the latter part of the weekend, long-range ensembles maintain that upper-level ridging will rebuild, yielding a return to warmer and drier weather for Sunday into early next week. At this point, there are 35-65% chances of reaching 80 degrees along much of the I-5 corridor on Mother`s Day. -36 && .AVIATION...A continued southwest push has brought marine stratus well inland to the Cascade crest resulting in widespread MVFR cigs of 1.5-2 kft early this morning. High-end IFR cigs of 800-1000 ft are most likely (70-90% chance) along the central Oregon coast south of KTMK, including KONP, through 18Z Tuesday. Inland and coastal terminals are expected to improve to VFR by approximately 23Z Tue as low clouds largely mix out, however there is a 10-20% chance low clouds will not scatter out at all today. Even if low clouds do scatter out, expect low clouds to fill back in quickly this evening into early tonight (most likely between 06-09Z Wednesday). This will result in another round of persistent MVFR cigs inland and IFR ceilings at the coast. Winds are expected to remain light and variable around 5 kt or less through 18Z Wednesday. KPDX AND APPROACHES...Light and variable winds around 5 kt or less will persist through 18Z Wednesday. Low stratus with MVFR cigs will remain in place throughout most of the 18Z TAF period, aside from a brief period of clearing expected between 23Z Tuesday and 08Z Wednesday. Note there is a 10% chance ongoing low clouds will fail to scatter out late this afternoon. If this were to occur, MVFR cigs would persist throughout the entire 18Z TAF period. -23 && .MARINE...A continued southerly surge will bring persistent low stratus through Wednesday with chances for fog and/or drizzle during the overnight and morning hours. Southerly winds around 5-10 kt this morning will turn westerly and weaken to 5 kt or less this afternoon into tonight. Winds look to turn northerly late Wednesday through much of Thursday, before a weak system moving onshore Friday into Saturday will see southerly flow return with gusts of 15-20 kt and low chances for rain showers. High pressure rebuilding this weekend will yield strengthening northerly flow, which may become hazardous to small craft late Sunday into Monday with gusts up to 20-25 kt. Chances for gusts to reach 21 kt or higher increase slightly from 20-60% on Sunday to 35-65% on Monday, with higher chances to the south. Seas will remain fairly steady at 4-7 ft with a persistent westerly to northwesterly swell through this weekend. -36/23 && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...None. && $$ www.weather.gov/portland Interact with us via social media: www.facebook.com/NWSPortland x.com/NWSPortland

694 FXUS66 KMFR 051106 AFDMFR Area Forecast Discussion National Weather Service Medford OR 406 AM PDT Tue May 5 2026 .DISCUSSION (Today through Monday)... Key Points: * Only minor impacts expected the next several days * Warm, above normal temperatures continue this week * Low pressure remains to our south today - Low chance for isolated showers and thunderstorms today * Drying trend starts Wednesday Further Details: A closed low remains to our south and will maintain northeast flow aloft. As we reach peak heating and convective temperatures, we could see showers and an isolated thunderstorm this afternoon and early evening. This would be mainly for areas along and near the Cascades/eastside areas, and parts of northern California. These chances are less than yesterday with only around 10%-15% chance for an isolated shower/thunderstorm. We are not expecting severe weather, but an occasional gust around 35-45 mph is possible. Chances are highest through peak heating this afternoon and early evening. High pressure aloft starts to nudge in tomorrow and will maintain dry conditions through the end of the week. Temperatures near 90 degrees will come to fruition Wed/Thurs for some areas. Slightly cooler temperatures expected on Friday, but warmer temperatures quickly return through the weekend and early next week. Lastly, will note that on Friday, a weak shortwave will enter the PacNW around Seattle. At this time, it does not appear to have any influence on the weather for our forecast area (outside of cooler temps), but there is an outside chance we could see light rainfall across coastal areas of both Douglas and Coos counties as well as northern Cascades areas north of Crater Lake. -Guerrero && .AVIATION (12 TAFs)... A marine layer will maintain IFR conditions along the coast impacting KOTH through much of this cycle. This has spilled over into the Umpqua Valley and the Rogue Valley which will maintain MVFR conditions at both KRBG and KMFR through this morning. Expecting conditions to clear up today for these inland, but not expecting much relief for North Bend. There is a low end chance for an isolated shower/thunderstorm today with KLMT having the relatively higher chance to see this threat. -Guerrero && .MARINE...Updated 400 AM PDT Tuesday, May 5, 2026....An extended period of relatively calm conditions will continue through Friday, with west-northwest swell dominated seas likely remaining below 8 ft. A thermal trough will develop this weekend, resulting in moderate north winds and steep seas through early next week. -Guerrero && .MFR WATCHES/WARNINGS/ADVISORIES... OR...None. CA...None. PACIFIC COASTAL WATERS...None. && $$

236 FXUS66 KEKA 050707 AFDEKA AREA FORECAST DISCUSSION National Weather Service Eureka CA 1207 AM PDT Tue May 5 2026 .SYNOPSIS...Showers taper off early this morning. Ridging fills in behind the low with warmer temperatures and clearer skies by mid week. && .DISCUSSION...A drier weather pattern starts today as showers taper off and move out of the area. High pressure will build through late week, bringing warmer than average temperatures but otherwise dry, seasonable, and mild weather. By Wednesday most interior valleys are forecast to be in the high 70s to low 80s. There is chance for the marine layer to finally clear out Wednesday, but this will likely return by late week. Confidence is increasing in much warmer interior temperatures this weekend into early next week as strong high pressure builds over the area. NBM is showing high probabilities for many of the interior valleys to see high temperatures over 90 by Sunday. Chances for over 95 are around 20- 40% for the warmest valleys. There is even a low-end chance (20%) for high temperatures over 100 degrees by Monday of next week for the valleys of southern Mendocino and Lake. && .AVIATION...(6Z TAFs)...MVFR to VFR conditions are being observed at the terminals. Generally IFR to MVFR ceilings are expected at all terminals through the early morning. Inland areas are expected to see lifting and clearing as drier conditions move in. Coastal areas may see some lifting and partial or temporary clearing, with MVFR to VFR conditions likely by the afternoon. Breezy north winds of around 10 kts or lower are possible this afternoon. JB && .MARINE...Light southwesterly winds are expected to become more northwest and eventually north today. Winds will generally be light at around 5 to 15 kts. Seas are dominated by a northwest swell around 7 feet at 13 seconds. There is also a second wave group of around 3 feet at 8 seconds. The waves remain dominated by a 3 to 4 foot wave at 12 seconds and a 2 to 4 foot wave around 5 to 8 seconds. The winds are generally expected to remain around 5 to 15 kt out of the north through the workweek. Late in the week a system moving by to the north may briefly switch the winds to the west or southwest. Over the weekend, high pressure returns and near gale to gale force northerly winds are expected to return. The waves are expected to remain fairly small, around 3 to 5 feet at 10 seconds. A new swell is expected to build to 4 to 6 feet at 14 seconds on Wednesday. MKK && .EKA WATCHES/WARNINGS/ADVISORIES... CA... None. NORTHWEST CALIFORNIA COASTAL WATERS... None. && $$ 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

018 FXUS66 KMTR 051720 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1020 AM PDT Tue May 5 2026 ...New AVIATION... .KEY MESSAGES... Updated at 1218 AM PDT Tue May 5 2026 - Cool temperatures and cloudy with light rain ending this morning - Warmer and drier conditions return for the middle of the week through the weekend && .UPDATE... Issued at 957 AM PDT Tue May 5 2026 We`re seeing pockets of light rain move south through the Bay Area into the Central Coast on the backside of an upper level disturbance that provided beneficial rainfall across much of the North Bay yesterday and last night. Locations that see rainfall will receive up to a few hundredths at most by early this afternoon. Cloud cover will continue to linger through sunset across most of our area. High temperatures will be in the upper 50s to low 60s, with mid/upper 60s farther inland. && .SHORT TERM... Issued at 1218 AM PDT Tue May 5 2026 (today and tonight) Rain totals over the North Bay have so far varied from 0.10" to as much as 0.50". Steady light to moderate rain will continue to move southward across the rest of the Bay Area through morning, likely affecting the morning commute with wet roads. A few areas of light drizzle and/or light rain may reach the north Central Coast. Isolated instability did produce a couple thunderstorms Monday evening. One thunderstorm developed over the coastal waters southwest of Point Arena and another over far northern Napa County. The 500 mb low pressure system is beginning to pick up speed and will move eastward while caught up in the subtropical jet stream. The rain diminishes later in the morning with drier conditions returning, however it may take some time for the sun to break through the clouds later today. Highs today are forecast to reach the 60s. Cloudy with patchy fog tonight with temperatures lowering to the 50s and 40s. && .LONG TERM... Issued at 1218 AM PDT Tue May 5 2026 (Wednesday through Monday) There`s good global model agreement that a high pressure system will move in across the forecast area during this timeframe. Expect dry weather along with a warming trend from mid to late week and the weekend. Compressional warming aloft and surface warming will result in above to well above normal high temperatures by late in the week and weekend. Far inland locations will reach the 80s and 90s. Moderate HeatRisk likely develops over inland locations by Sunday. Please stay tuned to the latest updates. && .AVIATION... (18Z TAFS) Issued at 1020 AM PDT Tue May 5 2026 A mix of MVFR and low-end VFR ceilings are being observed across the terminals, expected to continue through the early afternoon hours before ceilings lift and scatter. Gentle to moderate onshore winds will develop through the afternoon and evening before becoming light overnight. Extensive MVFR stratus is expected overnight owing to the deep marine layer and recent rainfall, especially in the North Bay. Stratus begins to clear out towards the end of the 24-hour TAF period, but clearing times are expected right at the end of the TAF period or shortly thereafter. Vicinity of SFO... MVFR ceilings continue for several more hours before the ceilings scatter out in the late afternoon and evening. Breezy west winds will persist through the afternoon and evening hours before becoming gentle overnight, as MVFR ceilings return to the terminal. Skies will clear out early Wednesday afternoon as breezy onshore winds resume. SFO Bridge Approach... Similar to SFO. Monterey Bay Terminals... VFR with mid- to high-level clouds persists today as gentle northwest winds develop in the afternoon and evening. MVFR ceilings develop in the evening and persist overnight as winds become light, with moderate confidence of some scattering out within the last hour of the TAF period. && .MARINE... (Today through Sunday) Issued at 957 AM PDT Tue May 5 2026 The gradient between high pressure over the Eastern Pacific and lower pressure over the western United States will support a gentle northwest breeze and moderate seas through Wednesday. This gradient will gradually tighten from Thursday through Saturday, causing winds to increase to a strong breeze and building rough seas for the weekend. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ SHORT TERM...JM LONG TERM....Canepa AVIATION...DialH MARINE...DialH 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

446 FXUS66 KOTX 051210 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 510 AM PDT Tue May 5 2026 .KEY MESSAGES... - Minor to locally moderate HeatRisk through Thursday. This level of heat primarily affects those who are sensitive to heat. - Dangerously cold water temperatures pose a high risk for cold water shock and hypothermia for anyone who unexpectedly falls in. Wear a life jacket if recreating on or near the water. && .SYNOPSIS... A prolonged period of above normal temperatures will continue into the middle of May. Conditions will be dry outside small chances for mountain showers in the North Idaho Panhandle each afternoon Wednesday through Saturday. && .DISCUSSION... Tuesday: Temperatures will be on the order of five degrees cooler courtesy of a backdoor cold front that moved through Monday night. The breezy north to northeast winds that developed with slowly relax through the day with continued dry conditions. High temperatures will reach the low 80s for valleys of Central WA and 70s for Eastern WA and North Idaho. Wednesday-Thursday: A shortwave ridge will lay into the region in the morning then flatten late afternoon and evening with the passage of a trough. There is a 20% chance for a few showers over North Idaho and extreme Northeastern WA with this trough, otherwise the main impacts will be increasing winds once again leading to elevated fire weather concerns. Temperatures warm back up another 3-5 degrees from Tuesday into the mid 70s to mid 80s while relative humidity levels dip lower near 20% and locally lower in the lee of the Cascades. The strongest winds will develop through the Cascade gaps and East Slopes driven by a sharper pressure gradient from a deepening marine layer west of the crest. Wind gusts will below 30 mph before 5PM then increase in the evening as the pressure gradient winds align with the evening downslope winds. East Wenatchee, Waterville, and Vantage have a 60% chance for observing gusts of 30 mph or stronger but only a 10-15% chance for reaching 40 mph. For much of the Central Columbia Basin, Spokane Area, and Palouse, wind gusts will be closer to 25 mph. Wind direction will be more typical of our marine pushes coming from the southwest early in the day and shifting to the west and northwest in the evening. The trough departs on Thursday with an upper-level ridge building back into the region through the day. Little to no weather impacts anticipated for Thursday with minor changes in temperatures. Some residual breeziness will be in place during the afternoon with gusts 15-20 mph though lighter than Wednesday evening, especially for Central WA. Friday-Monday: Generally good agreement in the ensembles for another shortwave trough to pass through on Friday delivering another bout of gusty winds and minimal precipitation. Greatest risk for showers and a few lightning strikes will be in the Idaho Panhandle (15-25% chance) indicating a mostly dry cold front passage for Central and Eastern WA. The Friday trough is a bit deeper vs Wednesday indicating higher probabilities for wind gusts > 30 mph for a larger portion of the region from the East Slopes to the Palouse. If there are changes to the forecast, it would include expanding a small chance for showers or thunderstorms into Eastern WA from North Idaho given some ensembles showing small amounts of CAPE supporting this change. The trough lingers over Idaho Saturday morning with a continued threat for showers until midday, otherwise yet another ridge of high pressure begins to build inland and into Central WA. The broad upper-level ridge will remain in place for Sunday and Monday promoting warm and dry conditions with high temperatures slowly rebounding back into the upper 70s to mid 80s by Monday. /sb && .AVIATION... 12Z TAFS: VFR conditions will prevail under mostly clear skies through 12z Wednesday. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in VFR conditions. 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 70 45 77 51 77 51 / 0 0 0 0 0 0 Coeur d`Alene 68 43 74 50 73 49 / 0 0 0 10 0 0 Pullman 69 45 74 51 71 48 / 0 0 0 0 0 0 Lewiston 75 47 79 54 78 51 / 0 0 0 0 0 0 Colville 75 43 80 46 81 48 / 0 0 0 10 0 0 Sandpoint 67 43 71 48 72 48 / 0 0 0 20 10 0 Kellogg 65 43 72 49 71 49 / 0 0 0 10 0 0 Moses Lake 80 50 85 51 82 49 / 0 0 0 0 0 0 Wenatchee 80 56 84 56 80 54 / 0 0 0 0 0 0 Omak 81 50 84 52 83 53 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...None. ID...None. && $$

717 FXUS66 KPDT 051127 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 427 AM PDT Tue May 5 2026 .KEY MESSAGES... - Above-normal temperatures and mostly dry conditions through the week - Breezy to windy each day Wednesday through Friday through the Cascade gaps and across the Columbia Basin and Blue Mountain foothills - Periods of low relative humidity and breezy to windy westerly winds Thursday and Friday through the Cascade gaps and across the Columbia Basin and Blue Mountain foothills && .DISCUSSION... Satellite imagery shows FEW-BKN mid-level clouds early this morning over the Columbia Basin and vicinity, with mostly clear skies elsewhere across the forecast area. Zooming out to examine the bigger picture, water vapor imagery reveals a ridge of high pressure offshore extending over the Pacific Northwest and Canadian Rockies. Meanwhile, a closed low is present over the Southwest and broad troughing is visible downstream over the northern Great Plains and central to northern Rockies. A switch to northerly to northeasterly winds is forecast by this afternoon across much of northeast Oregon and southeast Washington. Temperatures are generally expected to be several degrees cooler this afternoon relative to yesterday under the "cooler" northerly flow aloft, but are still forecast to be above normal for early May. Regarding precipitation chances, 00Z and 06Z CAMs show isolated showers developing this afternoon over the Cascade and Blue mountains where modest instability (CAM-advertised MUCAPE of 250-750 J/kg) develops, but chances of measurable precipitation are very low (5-15 percent) for any location so they have not received a "slight chance" mention in the gridded forecast. Looking ahead to Wednesday, NWP guidance is in good agreement that a weak shortwave will ride over the top of the ridge across British Columbia and the northern Rockies. This will induce a decently strong cross-Cascade pressure gradient (8-12 mb between PDX and GEG per latest guidance) and result in breezy to locally windy westerly winds through the Cascade gaps and across the Columbia Basin and Blue Mountain foothills. NBM probabilities of exceedance show a medium-high (40-80 percent) chance of reaching advisory-level wind gusts for climatologically wind-prone locations within the aforementioned region, with significantly lower chances elsewhere. Another round of breezy, though likely (70 percent confidence) not windy, conditions is forecast Thursday as upper-level ridging rebuilds over the Pacific Northwest. That said, a drier air mass is forecast to be present Thursday in the wake of the shortwave, and locally low relative humidity (10-15 percent) is forecast. By Friday, ensemble mean 500-hPa heights and vorticity show another shortwave from the Pacific entering the Pacific Northwest. While ensemble clusters show notable variance in strength and timing among solutions of the shortwave, confidence remains high (70 percent) in another round of widespread breezy to windy westerly winds through the Cascade gaps and across the Columbia Basin and Blue Mountain foothills. NBM probabilities of reaching or exceeding advisory-level wind gusts are medium-high (40-80 percent) for wind-prone areas within the region outlined above. Similar to Thursday, the dry air mass (ensemble-advertised PWATs of 0.25-0.50") coupled with sufficient downward mixing during the daytime should facilitate some low relative humidity (10-15 percent) prior to the arrival of a more humid air mass by later Friday. Taking a glance at the weekend into next week, ensemble NWP guidance shows little to no signal for organized precipitation until Tuesday as upper-level ridging remains the favored scenario for the bulk of the West. By Tuesday, 00Z ensemble clusters suggest a low (25 percent) chance of a return to some flavor of troughing for the region. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... VFR conditions with some mid- and high-level clouds and diurnally/terrain-driven winds of 5-15 kts (gusty in the afternoon) are forecast for the next 24 hours at all sites. && .Preliminary Point Temps/PoPs... PDT 78 50 83 54 / 0 0 0 0 ALW 78 53 82 56 / 0 0 0 0 PSC 83 51 88 54 / 0 0 0 0 YKM 83 53 87 52 / 0 0 0 0 HRI 83 51 85 55 / 0 0 0 0 ELN 78 50 79 49 / 0 0 0 0 RDM 78 43 81 43 / 0 0 0 0 LGD 73 46 78 49 / 0 0 0 0 GCD 75 45 78 46 / 0 0 0 0 DLS 83 56 83 54 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...86 AVIATION...86

864 FXUS65 KREV 050909 AFDREV Area Forecast Discussion National Weather Service Reno NV 209 AM PDT Tue May 5 2026 .KEY MESSAGES... * Showers and thunderstorms, with high Sierra snow showers, persist through this evening but with lower chances and coverage. * Gradual warm up along with drier weather prevails starting on Wednesday into the weekend. * Well above average temperatures return next week with western Nevada valleys potentially reaching 90F degrees. && .DISCUSSION... A line of showers continue across portions of western NV and the Sierra early this morning. This line will continue a southward track as the upper level trough continues its movement to the southeast towards SoCal and AZ. Hi-res models continue to show showers and thunderstorm continuing this afternoon. The main areas of concern will be south of Highway 50 and along the Sierra crest from NE CA to Mono county. Thunder chances remain at 10-30% through the afternoon and early evening, then drop after 8PM below 10%. Most of the rain and high elevation mountain snow should be done by 10 PM tonight, except for a few stray lingering light showers. Thunderstorm activity this afternoon will be is expected to be weaker than the last few days and with less coverage. MUCAPE values are around 100-600 J/kg during peak heating around 2-5 PM with 0-6 km shear in the 40-50 kts range, DCAPE around 300-800 J/kg, PW around 0.5 to 0.75" and mean winds aloft around 20 kts. Therefore, expect with any storm frequent lightning, small hail, gusty winds up to 45 mph, and periods of heavy rain that could lead to ponding of low-lying areas through this evening. Once the upper level trough leaves the region northerly flow remains keeping cool temperatures on Wednesday. Although, we should be warmer with less cloud cover. Temperatures will continue a gradual warm up trend as a high amplitude upper level ridge moves inland. This will lead to 5-15 degrees above average temperatures through Saturday. A very weak upper level disturbance in the PacNW will help in keeping the temperatures under control Friday. Late this weekend into early next week, temperatures will soar as a broader high pressure area settles over the Desert Southwest bringing more warm and dry air. This will potentially lead to the first 90 degree days of the season for western NV and NE CA valleys. -HC && .AVIATION... VFR conditions continue across much of the area with periods of MVFR near showers and thunderstorms through this evening. Thunder chances today will be 10-30% between 18-03Z then dropping below 10%. Showers will end in most areas by 06Z tonight. Mountain obscurations persist through 06-12Z tonight. Periods of FG are likely around KTRK early this morning, and again tonight leading to IFR to LIFR conditions. Winds will be light and VRB overnight, and from the north and northwest with gusts up to 20 kts between 19-03Z. However, stronger and erratic gusts up to 40 kts are possible near TSRA. -HC && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$

732 FXUS66 KSTO 041927 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1227 PM PDT Mon May 4 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Widespread showers and isolated thunderstorms today. Best chances for thunderstorms exist over the mountains and foothills. - Cooler temperatures and thunderstorm chances linger into Tuesday, with drying conditions midweek. - Hot and dry conditions are expected to develop end of the week and into next weekend, with Minor and Moderate HeatRisk && .DISCUSSION... ...Today through Tuesday... Latest RADAR shows scattered showers moving over the area this afternoon. Precipitation will be generally light but there may be a few pockets of moderate rainfall at times. Thunderstorm chances return this afternoon, with the highest likelihood (20-25%)over the mountains and foothills, however a few isolated cells moving into the Valley cannot be ruled out. Additional rainfall accumulations of 0.25 to 0.75 inches are expected over the central/southern Sacramento Valley and foothills, with 0.75 to 1.50 inches over the Sierra through Tuesday. South of Highway 50 there will be chances for snow through Tuesday, with minor accumulations 2 to 5 inches along the highest peaks. Snow levels are expected to remain above 8000 feet. Lingering showers will move over the mountains and foothills on Tuesday, with a 10-15% chance of thunderstorm development in the afternoon/early evening. Temperatures through Tuesday will be on the cooler side across the area, with highs in the 70s on Tuesday. ...Wednesday through Sunday... Conditions dry out as we move into Wednesday and continue into the weekend. Ensembles continue to favor upper level ridging building over the western United States late this week and into early next week. Temperatures gradually warm through midweek, climbing well above-normal by the weekend. Minor HeatRisk is expected across the Valley Wednesday, but becomes more widespread into the foothills and mountains by the end of the week. Areas of Moderate HeatRisk are expected in the Valley by Saturday, expanding to include the foothills by the weekend. The NBM currently indicates a 70-95% chance of high temperatures greater than 90 degrees in the Valley Saturday and Sunday. Be sure to hydrate and practice heat safety. Minimum RH values trend lower through the week as well, dropping into the 20s and teens by the weekend. This will coincide with a period of breezy north winds that develops on Saturday which could lead to elevated fire weather conditions in the central Sacramento Valley. Forecast gusts are between 15 and 25 mph. Looking into early next week, models are already hinting at the potential for triple digit temperatures as riding amplifies over the region. Currently, the NBM indicates a 50 to 70% chance of 100 or greater in the northern San Joaquin Valley and portions of the central Sacramento Valley next Monday. && .AVIATION... Areas of MVFR/local IFR conditions in showers, isolated thunderstorms, and/or low ceilings through Tuesday morning. Conditions will gradually improve in the Valley by Tuesday afternoon and evening. Lingering mountain showers or isolated thunderstorms Tuesday afternoon, mainly over the northern Sierra and southern Cascades. Gusty and erratic winds near thunderstorms. Otherwise, surface winds generally 12 kts or less. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$

319 FXUS65 KMSO 050852 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 252 AM MDT Tue May 5 2026 .DISCUSSION... KEY MESSAGES: - A backdoor cold front continues to bring cooler temperatures and northeast winds of 20 to 30 mph across western Montana today. - Boaters on Flathead Lake should anticipate choppy conditions returning today due to gusty northeast winds. - A warming trend begins Wednesday, though a disturbance will bring showers to northwest Montana late Wednesday, followed by showers and isolated thunderstorms along the Continental Divide on Thursday. A positively tilted ridge of high pressure building along the West Coast is keeping the Northern Rockies under northerly flow aloft. A north to south oriented jet streak will become situated over western Montana today. Closer to the surface, cooler, dense air to the east and warm air to the west will result in a strong easterly pressure gradient over western Montana. The bottom line is that strong northeasterly winds will continue this morning, turning more northerly later in the day. Winds speeds will remain below advisory criteria, but do expect choppy conditions on Flathead Lake throughout the day. Temperatures today will stay around normal for this time of year. The tight pressure gradient will relax on Wednesday as the ridge of high pressure moves over the Northern Rockies. The ridge will shut off the gusty northerly winds and initiate a warming trend, with western Montana valleys returning to the 70s and the lower valleys of north-central Idaho pushing into the 80s. However, this will not be a completely dry ridge. Most guidance indicates a disturbance will ride over the top of the ridge late Wednesday into Thursday. This atmospheric forcing will initially trigger showers across northwest Montana late Wednesday, particularly impacting the Glacier Park region. As the system progresses on Thursday, instability will increase slightly, shifting the threat southeastward and bringing showers and isolated thunderstorms primarily along the Continental Divide. Some ensemble solutions (about 40%) show another weak disturbance on Saturday bringing widespread rain. && .AVIATION...VFR conditions will prevail across the Northern Rockies airspace. The persistent easterly or northeasterly winds of about 20-30 knots continue at KMSO and KGPI, while KHRF and KSMN will see a shift to northerly winds by about 05/2200Z. Winds remain elevated into tonight before relaxing on Wednesday as a ridge of high pressure moves over the Northern Rockies. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...None. && $$

911 FXUS65 KBOI 051640 AFDBOI Area Forecast Discussion National Weather Service Boise ID 1040 AM MDT Tue May 5 2026 .UPDATE...Updated aviation discussion. && .KEY MESSAGES... - Windy conditions this afternoon with northerly winds. - Isolated afternoon/evening showers and thunderstorms today over the mountains of S Idaho and SE Oregon, otherwise dry. - Above normal temperatures continue with 10-15 degrees above normal by next week. && .SHORT TERM /Through Thursday Night/... Issued 406 AM MDT TUE MAY 5 2026 Northerly flow will continue over the area as a trough remains over southern CA, with cool air east of the Rockies and a ridge over SW British Columbia. Air flow will converge over the central ID mountains and Magic Valley, as air from eastern OR converges with air from eastern ID and MT moving down the Snake Basin. This convergence zone favors isolated showers and thunderstorms Tuesday afternoon. Elsewhere windy northerly conditions expected Tuesday afternoon with gusts of 30 to 40 mph. Northwest flow continues into Thursday with dry and breezy conditions during the afternoon. Temperatures range around 5 to 10 degrees above normal in the short term. && .LONG TERM /Friday through Tuesday/... Issued 406 AM MDT TUE MAY 5 2026 A dry cold front will move through the area on Friday afternoon, bringing breezy conditions and lowering temperatures to near normal. Then the upper level ridge redevelops over the western US, with the warmest temperatures of the season by next Monday and Tuesday. Temperatures rise 15 to 20 degrees above normal with highs of 85 to 90 degrees in the Snake Basin. && .AVIATION /18Z Tuesday through Wednesday/... Issued 1034 AM MDT TUE MAY 5 2026 VFR. Areas of smoke. Isolated showers/thunderstorms across the higher terrain of southeast Oregon and central ID mountains this afternoon and evening. 30% chance of thunderstorms affecting KTWF/KJER between 05/22Z and 06/02Z. Gusty erratic outflow winds possible with the stronger storms. Surface winds: W-NW 15-25 kt with gusts up to 35 kt through the evening. Becoming light and variable overnight. Winds aloft at 10k ft MSL: N 15-30 kt. KBOI...VFR. Cumulus buildups east of terminal this afternoon. Surface winds: NW 15-20 kt with gusts around 30 kt this afternoon. Becoming SE 10-20kt after 06/08Z. && .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.....JR SHORT TERM...KA LONG TERM....KA

726 FXUS65 KLKN 050811 AFDLKN Area Forecast Discussion National Weather Service Elko NV 111 AM PDT Tue May 5 2026 .KEY MESSAGES... * Periods of valley rain and high elevation snow through Tuesday evening * A few strong thunderstorms possible Tuesday afternoon * Warming trend Wednesday through Friday && .UPDATE... Issued at 104 AM PDT Tue May 5 2026 Forecast appears to be on track for continued valley rain mountain snow through Tuesday evening with potential for more convection Tuesday afternoon. No changes needed at this time. && .DISCUSSION... (Today through next Tuesday) WEATHER PATTERN OVERVIEW: A few strong thunderstorms are possible Tuesday afternoon. The primary thunderstorm hazards will be wind gusts of 45 to 50 mph and dangerous cloud to ground lightning strikes. A storm system will impact Northern and Central Nevada through Tuesday evening, resulting in periods of valley rain and high elevation snow. Snow levels will remain around 9,000 feet. The majority of this precipitation will fall Tuesday afternoon. A ridge of high pressure will build northeastward across the Silver State Wednesday through Friday, resulting in a warming trend. By Friday afternoon, high temperatures throughout Northern and Central Nevada will be around ten degrees above normal for this time of year. Maximum temperatures across Northern and Central Nevada will remain above seasonal values this weekend. FORECAST CONFIDENCE & DEVIATIONS: High forecast confidence regarding a few strong thunderstorms Tuesday afternoon. High forecast confidence in periods of valley rain and high elevation snow through Tuesday evening. Moderate forecast confidence regarding a warming trend Wednesday through Friday. No deviations from the NBM model output. && .AVIATION... VFR conditions will prevail at all terminals through at least the next 24 hours. MVFR or lower conditions are conceivable in and near precipitation. This possibility is not high enough for inclusion in the terminal forecasts. && .FIRE WEATHER... A few strong thunderstorms are expected Tuesday afternoon into this evening. The primary thunderstorm hazards will be wind gusts near 50 mph and dangerous cloud to ground lightning strikes. The most likely area for thunderstorms will be in Southern Elko County, Northern White Pine County, and Eureka County. && .LKN Watches/Warnings/Advisories... None. && $$ UPDATES...99 DISCUSSION...87 AVIATION...87 FIRE WEATHER...87