Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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289 FXUS66 KOTX 081128 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 428 AM PDT Mon Jul 8 2024 .SYNOPSIS... Hot temperatures will continue through the upcoming week. The hottest days will be Tuesday and Wednesday with widespread triple digit heat. Breezy to gusty winds return Wednesday with increasing fire weather concerns. && .DISCUSSION... ...ONGOING HEATWAVE DELIVERING NEAR RECORD HEAT THROUGH WEDNESDAY... ...INCREASED FIRE WEATHER DANGER THROUGH WEDNESDAY... Key messages for the week - Hot to very hot temperatures are here and will be in place through Wednesday - Tuesday and Wednesday will deliver the hottest afternoon temperatures and warmest overnight lows - Red Flag Warnings and Fire Weather Watches in effect for some areas MON through WED - Temperatures cool 10 degrees Thursday then warm again heading into the weekend - No precipitation is in sight Heat: Strong upper level has become established over the region and will remain anchored through Tuesday then flatten on Wednesday as shortwaves swing into southern BC. On Sunday, temperatures reached the triple digits at locations like Lewiston, Ephrata, Omak, Winthrop, Stehekin, Moses Lake, and Priest Rapids Dam. Priest Rapids Dam was the winner coming in at 105F with Omak a close second at 103F. The air mass will continue to warm today and Tuesday with another 1-3 degrees of warming each consecutive day. By Wednesday, we start to see temperatures come down 1-2 degrees in Central WA and remain steady or possibly 1 warmer for Idaho and eastern reaches of WA. Tuesday and Wednesday will feature the hottest readings of this heatwave with numerous communities between 102-110F. Overnight lows have been pleasant in our northern mountain valleys but have remained in the upper 60s to 70s for our lowest elevations and Basin. Low temperatures will also be coming up 1-3 degrees each night. Excessive heat warnings are meant to capture the areas that will carry the greatest risk for overnight lows of 65-75 offering little to no relief at night. It is advised to take the heat seriously and follow precautions to avoid heat stress. This includes taking breaks often, staying hydrated, and finding air conditioned areas when applicable. Be sure to check in occasionally on your furry friends, elders, and other sensitive to heat. Fire Weather: Red Flags are currently in effect for the Cascades and Pioneer Fire. This pattern has a history of rapid fire growth for these fire zones given the hot temperatures, long burn periods (poor overnight RH recoveries), and unstable weather conditions. Any new starts anywhere in the region will also be exposed to these hot, dry, unstable conditions and could result in rapid fire growth where terrain/slope plays a role. Please be cautious out there. A fire weather watch has been issued for Wednesday afternoon and evening for Central WA. As the ridge begins to flatten, winds will be on the increase region-wide. Central WA carries the greatest risk for sustained winds of 15-20 mph with gusts near 30 mph. The L-C Valleys, Foothills of the Blue Mountains, Palouse, eastern Basin including Ritzville, Davenport, and Spokane, and Colville Reservation are other areas that will be in the elevated status meaning winds steady winds will be present but speeds are less likely to reach sustained speeds of 15 mph or stronger. This will need to be monitored over the next 24 hours for potential changes in the guidance. Winds on Wednesday will come with temperatures in the 90s-100s and RH values in the teens. Smoke: The Pioneer Fire burning south of Stehekin on Lake Chelan will have high probabilities to remain active given the projected weather pattern. Smoke from the fire will settle into the lake basin overnight with a drift downlake toward Manson and Chelan overnight and uplake during the day. Deeper plumes of smoke during the day will bring the potential for smoke into the Methow Valley as well. Air quality is likely to be impacted at times. Please refer to fire.airnow.gov for the latest readings and smoke outlooks. Thursday through Sunday: Temperatures will cool 10 degrees on Thursday with a flatter ridge in place with readings still in the 90s; we`ll call it warm zonal flow. The air mass also becomes quite dry behind the front with PWATs lowering from 0.50 to 0.25 Wednesday night and Thursday so despite the cooling, RH values will remain very low with continued elevated fire weather conditions. Overnight lows will feel much better however with readings in the 50s-60s. The thermometer will be on the rise again for the weekend. There is still moderate uncertainty with the placement of an offshore low and the re- amplification of the interior ridge. It is conceivable that temperatures rebound back into the upper 90s or even lower 100s. What does seem likely is winds will remain "breezy" each afternoon from THU-SAT with steady speeds 8-14 mph and gusts near 20 mph which could be problematic for any new ignitions given the new state of the fuels following the heatwave. /sb && .AVIATION... 12Z TAFS: VFR conditions will prevail. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence in VFR conditions. ----------------------- 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 100 67 103 68 104 65 / 0 0 0 0 0 0 Coeur d`Alene 97 66 100 67 102 61 / 0 0 0 0 0 0 Pullman 96 64 100 65 101 60 / 0 0 0 0 0 0 Lewiston 105 73 109 74 111 70 / 0 0 0 0 0 0 Colville 98 59 101 60 102 57 / 0 0 0 0 0 0 Sandpoint 93 61 100 59 99 58 / 0 0 0 0 0 0 Kellogg 93 67 98 71 102 63 / 0 0 0 0 0 0 Moses Lake 104 67 107 68 107 65 / 0 0 0 0 0 0 Wenatchee 104 74 108 75 104 69 / 0 0 0 0 0 0 Omak 105 73 108 74 107 66 / 0 0 0 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...Heat Advisory until 10 PM PDT Wednesday for Central Panhandle Mountains-Northern Panhandle. Excessive Heat Warning until 10 PM PDT Wednesday for Coeur d`Alene Area-Idaho Palouse-Lewis and Southern Nez Perce Counties-Lewiston Area. WA...Heat Advisory until 10 PM PDT Wednesday for Northeast Mountains- Okanogan Highlands-Western Chelan County. Excessive Heat Warning until 10 PM PDT Wednesday for Central Chelan County-Lower Garfield and Asotin Counties-Moses Lake Area-Northeast Blue Mountains-Okanogan Valley-Spokane Area- Upper Columbia Basin-Washington Palouse-Waterville Plateau- Wenatchee Area-Western Okanogan County. Fire Weather Watch from Wednesday afternoon through Wednesday evening for East Portion of North Cascades National Park/Lake Chelan National Recreation Area (Zone 697)-East Washington Central Cascades (Zone 696)-Foothills of Central Washington Cascades (Zone 705)-Methow Valley (Zone 704)- Okanogan Valley (Zone 703)-Waterville Plateau (Zone 706)- Western Columbia Basin (Zone 707). Red Flag Warning from noon today to 11 PM PDT Tuesday for East Portion of North Cascades National Park/Lake Chelan National Recreation Area (Zone 697)-East Washington Central Cascades (Zone 696)-East Washington North Cascades (Zone 698). && $$