537  
FXUS66 KOTX 210632  
AFDOTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SPOKANE WA  
1132 PM PDT THU AUG 20 2026  
   
KEY MESSAGES
 
 
- A HEAT ADVISORY HAS BEEN ISSUED FOR FRIDAY AFTERNOON THROUGH  
EVENING DUE TO VERY WARM TEMPERATURES AND WIDESPREAD MAJOR  
HEATRISK.  
 
- SATURDAY SYSTEM BRINGS INCREASED CHANCES FOR SHOWERS,  
THUNDERSTORMS, AND GUSTY WINDS. THIS WILL LEAD TO CRITICAL  
FIRE WEATHER CONDITIONS ACROSS THE INLAND NORTHWEST.  
 
- PATCHY BLOWING DUST IS POSSIBLE IN THE WESTERN COLUMBIA  
BASIN.  
 

 
   
SYNOPSIS
 
 
TEMPERATURES WILL VERY WARM TODAY WITH INCREASING MID AND HIGH  
CLOUDS. A PATTERN CHANGE OVERNIGHT INTO SATURDAY WILL BRING  
COOLER, UNSETTLED CONDITIONS WITH CHANCES FOR SHOWERS,  
THUNDERSTORMS, AND GUSTY WINDS. SUNDAY WILL REMAIN BREEZY BUT  
COOLER AND CONTINUED DRY. NEXT WEEK WILL BE WARMER TO START THE  
WEEK WITH BREEZY CONDITIONS RETURNING MIDWEEK.  
 

 
   
DISCUSSION
 
 
TODAY: THE RIDGE AXIS THAT WAS OVER THE INLAND NW ON THURSDAY  
WILL BEGIN TO SHIFT EASTWARD INTO THE IDAHO PANHANDLE AS A DEEP  
LOW WOBBLES TOWARD THE WA COAST. THIS WILL ALLOW AN INFLUX OF  
MID AND HIGH LEVEL MOISTURE TO DRIFT NORTHWARD INTO THE REGION  
BRINGING FILTERED SUNSHINE. TEMPERATURES WILL REMAIN WARM  
TOPPING OUT IN THE MID TO UPPER 90S WITH WITH SOME AREAS  
POTENTIALLY REACHING THE CENTURY MARK. THE AIR MASS WILL SUPPORT  
WARMER TEMPERATURES THAN THURSDAY BUT THE PRESENCE OF HIGH  
CLOUDS DOES ADD A DECENT AMOUNT OF UNCERTAINTY EXACTLY HOW WARM  
CONDITIONS WILL BE. WINDS WILL BE LIGHT WITH A MODERATE AMOUNT  
OF TERRAIN INFLUENCE. AREAS WHICH EXPERIENCE NORTHEAST TO EAST  
WINDS COULD SEE PERIODS OF BREEZY CONDITIONS NEAR 10 MPH DUE TO  
THE ALIGNMENT WITH THE GENERAL WINDS AS THEY BEGIN TO BE  
INFLUENCED BY THE APPROACHING LOW PRESSURE SYSTEM.  
 
OVERNIGHT INTO SATURDAY NIGHT: THE LOW CONTINUES TO DRIFT TOWARD  
THE COAST OVERNIGHT AND INTO WESTERN WA ON SATURDAY. A WEAK  
IMPULSE MOVING OUT AHEAD OF THE LOW WILL COME THROUGH THE REGION  
BRINGING AN INCREASED RISK FOR ELEVATED SHOWERS OR SPRINKLES.  
SOME HI-RES MODELS INDICATE A SMALL THREAT (5-10%) CHANCE FOR A  
FEW LIGHTNING STRIKES BUT THIS COMES WITH VERY LOW CONFIDENCE  
DUE TO 850-300MB CAPE ONLY ON THE ORDER OF 50-100 J/KG AND VERY  
WEAK FORCING. HREF ALSO ADVERTISES NEAR ZERO PROBABILITIES FOR  
LIGHTNING OVERNIGHT, A MODEL THAT HAS DONE WELL THROUGH THE  
COURSE OF THE SUMMER. HRRR ON THE OTHER HAND, HAS SOME THREAT AS  
DO A FEW OTHER HI-RES MODELS SO IT WILL BE SOMETHING TO MONITOR  
GIVEN ITS HIGH BASED NATURE AND LITTLE TO NO RAINFALL  
ASSOCIATED WITH IT.  
 
AS WE HEAD INTO SATURDAY, THE WEATHER BECOMES A BIT MORE DYNAMIC  
AS STRONGER LIFT ARRIVES. AT THIS TIME, THE WAY THINGS ARE  
STARTING TO EVOLVE COME IN DIFFERENT WAVES. FIRST WILL BE THE  
THREAT FOR SHOWERS AND THUNDERSTORMS ALONG THE CASCADES SATURDAY  
MORNING WITH SOME ACTIVITY LINGERING NEAR THE CANADIAN BORDER  
IN THE AFTERNOON. SECOND WILL BE SHOWERS AND THUNDERSTORMS  
DEVELOPING OVER THE IDAHO PANHANDLE AND EXTREME SOUTHEASTERN WA  
SATURDAY AFTERNOON AND CONTINUING IN DIFFERENT WAVES OVERNIGHT.  
BOTH AREAS HAVE THE POTENTIAL FOR ISOLATED STRONG STORMS WITH  
THE HIGHER THREAT LEANING TOWARD THE IDAHO PANHANDLE GIVEN THE  
ACTIVITY ALIGNING WITH PEAK HEATING. GUSTY OUTFLOW WINDS,  
LIGHTNING AND FIRE STARTS, AND BRIEF DOWNPOURS OF RAIN AND HAIL  
WILL BE A CONCERN WITH AN CELLS.  
 
IN BETWEEN THESE THUNDERSTORM AREAS, THE MAJOR CONCERN WILL BE  
CRITICAL FIRE WEATHER CONDITIONS FROM GUSTY WINDS AND HOT, DRY  
CONDITIONS. AN INDEX USED FOR THIS IS THE HOT, DRY, WINDY INDEX  
WHICH IS SHOWING AREAS OF THE COLUMBIA BASIN WELL INTO THE 95TH  
PERCENTILE. THERE IS REASONABLE AGREEMENT AMONGST THE MODELS FOR  
A SURFACE LOW TO DEEPEN OVER NE WA OR CLOSE TO THE CANADIAN  
BORDER AS THE LOW IS DRIFTING INLAND INITIALLY PULLING SOUTH  
WINDS ACROSS THE WESTERN BASIN AND INTO THE OKANOGAN VALLEY THEN  
STARTING TO SPREAD EASTWARD WHILE SHIFTING TO THE SOUTHWEST AS  
THE LOW BEGINS TO TRACK EAST AND COOLER AIR FLOODS INLAND  
DRAGGING A COLD FRONT THROUGH. WINDS ACROSS THE EAST SLOPES WILL  
LARGELY FOLLOW THE FOOTPRINTS OF THE TERRAIN AND COME FROM THE  
WEST/NORTHWEST. STRONGEST WINDS ON SATURDAY LOOK TO SETUP ACROSS  
THE WESTERN COLUMBIA BASIN AND INTO THE OKANOGAN VALLEY WHERE  
SUSTAINED SPEEDS WILL BE CLOSER TO 20-25 MPH WITH GUSTS OF 30-35  
MPH. THE SPOKANE AREA AND FOOTHILLS OF THE NORTHERN MOUNTAINS  
WILL BE WINDY, BUT SPEEDS LOOK TO BE A FEW MPH LIGHTER WITH  
SPEEDS OF 15-20 MPH AND GUSTS TO 30 MPH. THE STRONGEST WINDS FOR  
THE EASTERN BASIN, PALOUSE, L-C VALLEY, AND FOOTHILLS OF THE  
BLUE MOUNTAINS WILL ARRIVE LATER IN THE DAY AND INTO THE EVENING  
AS THE COLD FRONT PRESSES THROUGH AND WOULD NOT RULE OUT GUSTS  
CLOSE TO 35 MPH WHEN THIS OCCURS. OVERALL, IT LOOKS TO BE A VERY  
IMPACTFUL DAY IN REGARDS TO FIRE WEATHER FOR NEW STARTS AND  
WIND DRIVEN FIRES. WE WILL ALSO NEED TO WATCH FOR BLOWING DUST  
ON SATURDAY AROUND MOSES LAKE, RITZVILLE, WILBUR, AND OMAK.  
 
WHILE LIGHTNING MAY BE LIMITED ACROSS THE NORTHERN MOUNTAINS  
DURING THE DAY AS THE WINDS ARE BLOWING, THE LOW WILL MOVE  
THROUGH NORTHERN WA AND INTO SOUTHERN BC SATURDAY NIGHT INTO  
SUNDAY. THIS WILL KEEP THE THREAT FOR SHOWERS AND THUNDERSTORMS  
GOING 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: THE PATTERN IS SETTING UP TO BE QUITE A  
ROLLER COASTER AND HAS PLENTY OF SUPPORT FROM THE ENSEMBLE  
SUITES. HIGH PRESSURE MOVES IN MONDAY AND TUESDAY PROMOTING A  
WARMING AND DRYING TREND. THIS IS QUICKLY INTERRUPTED BY ANOTHER  
ROBUST 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
 
 
06Z TAFS: VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE  
TAF PERIOD THOUGH THICKENING MID AND HIGH CLOUDS WILL BE MOVING  
IN FROM THE SOUTH WITH CIGS VARYING FROM 15-20K FT AGL. A WEAK  
NORTHEAST PRESSURE GRADIENT WILL RESULT IN ELEVATED WINDS FOR  
KCOE AND KPUW FOR A FEW HOURS IN THE MORNING 14-18Z WITH SPEEDS  
NEAR 10KTS, OTHERWISE WINDS WILL BE LIGHT AND LESS THAN 10 KTS  
FOR MOST LOCATIONS. SMOKE FROM LOCAL WILDFIRES WILL BRING THE  
POTENTIAL FOR REDUCTIONS IN VISIBILITY, ESPECIALLY FOR  
WENATCHEE, CHELAN, WINTHROP, AND OMAK. SMOKE MODELS SHOW EAT  
REMAINING AT OR BELOW 6SM THROUGH THE TAF PERIOD. FOR ALL OTHER  
TERMINALS, SMOKE MODELS SHOW VISIBILITIES ARE EXPECTED TO REMAIN  
VFR AT 6SM OR GREATER WITH AREAS OF HAZE DRIFTING ACROSS  
NORTHEASTERN WA AND NORTH IDAHO.  
 
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: HIGH CONFIDENCE  
IN LIGHT WINDS AND VFR CONDITIONS FOR ALL TAF SITES. GREATEST  
UNCERTAINTY IS VISIBILITY FOR KEAT. VISIBILITY AT KEAT WAS  
REDUCED TO 2SM THURSDAY MORNING AND MAY HIT SIMILAR RESTRICTIONS  
IF THE UPSTREAM SMOKE GETS DRAWN DOWN THE RIVER DRAINAGE. GIVEN  
THE LOW CONFIDENCE, FORECAST IS A OPTIMISTIC TO REMAIN AROUND  
4SM OR HIGHER AT THIS TIME. /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 94 59 97 66 94 59 / 0 0 0 10 0 30  
COEUR D'ALENE 93 60 98 67 95 60 / 0 0 0 10 0 40  
PULLMAN 93 55 98 60 90 51 / 0 0 0 20 10 30  
LEWISTON 99 66 103 72 98 64 / 0 0 0 20 10 20  
COLVILLE 93 52 96 58 93 52 / 0 0 0 10 10 30  
SANDPOINT 90 56 94 62 92 55 / 0 0 0 10 10 40  
KELLOGG 91 58 96 63 92 55 / 0 0 0 10 10 40  
MOSES LAKE 95 59 99 68 94 55 / 0 0 0 10 10 10  
WENATCHEE 95 69 97 75 92 62 / 0 0 0 10 30 0  
OMAK 95 64 98 71 95 59 / 0 0 0 10 20 20  
 

 
   
OTX WATCHES/WARNINGS/ADVISORIES
 
 
WA...HEAT ADVISORY FROM 11 AM TO 10 PM PDT FRIDAY FOR CENTRAL  
CHELAN COUNTY-LOWER GARFIELD AND ASOTIN COUNTIES-MOSES  
LAKE AREA-NORTHEAST BLUE MOUNTAINS-NORTHEAST MOUNTAINS-  
OKANOGAN HIGHLANDS-OKANOGAN VALLEY-SPOKANE AREA-UPPER  
COLUMBIA BASIN-WASHINGTON PALOUSE-WATERVILLE PLATEAU-  
WENATCHEE AREA-WESTERN OKANOGAN COUNTY.  
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY  
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 10 AM PDT FRIDAY FOR CENTRAL CHELAN  
COUNTY-MOSES LAKE AREA-OKANOGAN HIGHLANDS-OKANOGAN VALLEY-  
UPPER COLUMBIA BASIN-WATERVILLE PLATEAU-WENATCHEE AREA-  
WESTERN CHELAN COUNTY-WESTERN OKANOGAN COUNTY.  
FIRE WEATHER WATCH FROM SATURDAY MORNING THROUGH SUNDAY  
MORNING 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 FROM 11 AM TO 10 PM PDT FRIDAY FOR CENTRAL  
PANHANDLE MOUNTAINS-COEUR D'ALENE AREA-IDAHO PALOUSE-  
LEWIS AND SOUTHERN NEZ PERCE COUNTIES-LEWISTON AREA-  
NORTHERN PANHANDLE.  
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY  
MORNING FOR NORTHERN AND CENTRAL IDAHO PANHANDLE (ZONE  
101).  
AIR QUALITY ALERT UNTIL 3 PM PDT FRIDAY FOR LEWIS AND SOUTHERN  
NEZ PERCE COUNTIES-LEWISTON AREA.  
 

 
 

 
 
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