FXUS66 KOTX 221646 AFDOTX Area Forecast Discussion National Weather Service Spokane WA 946 AM PDT Sat Aug 22 2026 .KEY MESSAGES... - A Heat Advisory has been extended for Northeastern WA and North Idaho for Saturday. - Saturday will bring critical fire weather conditions across the Inland Northwest due to a combination of isolated to scattered thunderstorms producing gusty outflow winds, along with breezy winds and low relative humidity. - Patchy blowing dust is possible Saturday in the Western Columbia Basin. && .SYNOPSIS... A weather system passing through on Saturday will bring critical fire weather conditions across the Inland Northwest. This is due to a combination of isolated to scattered thunderstorms producing gusty outflow winds, along with breezy winds and low relative humidity. Sunday will remain breezy and dry, but cooler. Temperatures will warm again at the start of next week with breezy conditions returning by the middle of next week. && .DISCUSSION... Today: A deep low begins its migration into the region. Midlevel moisture is streaming inland ahead of the low bringing heavy mid and high level clouds along with sprinkles and light showers. There has been a few lightning strikes near Lewiston this morning where there are a few midlevel circulations noted within the midlevels. Would not rule out a few strikes with additional activity in Central WA either due to subtle circulations showing up in the water vapor. The air mass is very warm and dry near the surface. As such, any rain falling is largely evaporating but this is leading to erratic wind gusts upwards of 15 to 20 mph. Several of the high resolution models are indicating that a few cells that can drive rain to the surface could result in gusts as high as 40 mph. This band of moisture and shower activity will slowly lift south to north and clear across the International border early Saturday morning and the upper low will begin to migrate to the WA Coast, into the North Cascades overnight and across NE WA and N ID Sunday morning. As the low and associated 500mb cold pool migrates inland, lapse rates will continue to steepen with lower levels remaining in the 90s. Areas of NE WA and N ID will only cool 3-4 degrees from Friday and Heat Advisories have been extended. One of the main concerns for Saturday will be the potential for thunderstorms developing. Initially, storms are expected to fire over the North Cascades where the upper level cooling will arrive closer to midday but as impulses rotate around the low and eject inland the potential for cells to develop over Idaho, Eastern and northern WA will increase. This looks to be closer to late afternoon into the evening hours. Any cells through the day, rain or thunderstorms that produce precipitation shafts will likely result in gusty outflow winds of 25 to 50 mph given the high based nature of this convection, extremely dry subcloud layers, and DCAPES of 500-1500 J/kg. In the most intense outflows, winds could gust closer to 60 mph. This will be closely monitored through the day as will lightning strikes and fire starts. Winds will be the other major concern through the day. Away from outflow boundaries, strong synoptic driven winds will develop across a majority of the region, especially the Western Columbia Basin and through the Cascade Gaps. Winds will initially strengthen from the south then shift to the southwest and west late in the day into the evening as cooler air floods inland. Any ongoing or new fires will stand a good chance to be fanned by gusty winds of 25-35 mph. Given our fuel dryness levels, this is very concerning. Red Flag Warnings are in place across the region to account for the synoptic winds, outflow winds, and lightning starts. Generally speaking, the Cascades, Northern Mountains, and Idaho Panhandle are in fire weather highlights for the lightning starts and gusty outflow winds though the Cascades will experience a period of strong synoptic winds Saturday evening as the cooler air floods into the region. This will draw higher humidity levels but it will take several hours for the fuels to react. We expect very little lightning in the Western and Southern Columbia Basin so this will mainly be a wind and low humidity issue. For the eastern Basin, the combination of periods of gusty winds and isolated thunderstorms in the late afternoon and evening hour makes this a dual threat for fire weather. We will also need to watch for blowing dust on Saturday around Moses Lake, Ritzville, and Wilbur with a lower threat for Omak than previously thought. The gusty winds could also lead to blowing ash near any fire scars. The threat for showers and thunderstorms will continue well into the evening and overnight hours while winds remain elevated region-wide. The main threat for thunderstorms on Sunday will be in the morning with the system departing to the east and breezy winds becoming the most impactful weather through the day while temperatures cool back into the 80s. Monday through Friday: Ensembles continue to advertise a progressive weather pattern next week. High pressure moves in Monday and Tuesday promoting a warming and drying trend. This is quickly interrupted by another shortwave Wednesday. The exact depth and track of this through the NW comes with some uncertainty but pattern recognition would suggest another bout of windy conditions and possibly some thunderstorms. The pattern repeats itself again Thursday and Friday with the next system Friday into Saturday. We are not seeing a lot of signs for appreciable rainfall with these systems indicating fire weather concerns will remain elevated or higher as we navigate the end of August. /sb && .AVIATION... 18Z TAFs: A midlevel front lifting to the northeast will usher elevated showers and embedded thunderstorms through the forecast area this morning. Brief rain and dry subcloud layers support erratic winds near 25 mph with this activity. This will lift out of KEAT-KMWH by 20z and KGEG-KPUW 20-23z. As this activity departs, additional instability and an incoming system will renew chances for isolated to scattered thunderstorms through the late afternoon and well into the overnight hours. A few cells could be strong with wind gusts in excess of 50 mph. Greatest risk will be over the northern mountains, Idaho Panhandle, and into the far eastern reaches of WA. This includes KLWS, KPUW, KGEG, KSFF, and KCOE. The incoming system will bring gusty winds to much of Central WA with winds shifting from southeast to southwest and west in the evening. Local gusts near 30kts possible around KEAT. Winds will remain elevated overnight into Sunday morning as the system tracks inland. Smoke from the Cascade fires will continue to impact KEAT at times. FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Low confidence for TS at terminals but moderate confidence for outflow winds to impact most terminals with speeds of at least 20-30 mph. SB ----------------------- 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 95 59 81 54 86 56 / 10 20 0 0 0 0 Coeur d'Alene 95 60 80 53 86 56 / 10 40 10 0 0 0 Pullman 90 51 77 45 85 50 / 10 30 0 0 0 0 Lewiston 97 62 86 58 91 62 / 20 30 0 0 0 0 Colville 94 51 80 44 86 47 / 30 20 20 0 0 0 Sandpoint 93 54 77 47 82 50 / 20 40 10 0 0 0 Kellogg 93 54 76 52 83 54 / 20 40 0 0 0 0 Moses Lake 94 55 85 53 88 56 / 10 0 0 0 0 0 Wenatchee 93 63 83 61 87 65 / 20 0 0 0 0 0 Omak 94 56 84 55 88 58 / 30 20 10 0 0 0 && .OTX WATCHES/WARNINGS/ADVISORIES... WA...Heat Advisory until 7 PM PDT this evening for Northeast Mountains-Spokane Area. Red Flag Warning from 4 PM this afternoon to 11 AM PDT Sunday for Selkirk Mountains of Northeast Washington (Zone 700). Red Flag Warning from noon today to 10 PM PDT this evening for Colville Reservation (Zone 702)-Eastern Columbia Basin - Palouse -Spokane Area (Zone 708)-Foothills of Central Washington Cascades (Zone 705)-Foothills of Northeast Washington (Zone 701)-Lower Palouse -Snake River (Zone 709)-Waterville Plateau (Zone 706)-Western Columbia Basin (Zone 707). Air Quality Alert until 2 PM PDT Monday for Central Chelan County-Okanogan Highlands-Okanogan Valley-Upper Columbia Basin-Waterville Plateau-Wenatchee Area-Western Chelan County-Western Okanogan County. Red Flag Warning from 11 AM this morning to 8 AM PDT Sunday 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)-Methow Valley (Zone 704)- Okanogan Highlands and Kettle Mountains (Zone 699)- Okanogan Valley (Zone 703). ID...Heat Advisory until 7 PM PDT this evening for Central Panhandle Mountains-Coeur d'Alene Area-Idaho Palouse- Lewiston Area-Northern Panhandle. Red Flag Warning from 4 PM this afternoon to 11 AM PDT Sunday for Northern and Central Idaho Panhandle (Zone 101). && $$