452
FXUS66 KOTX 122105
AFDOTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
205 PM PDT TUE MAY 12 2026
KEY MESSAGES
- VERY WARM TEMPERATURES THROUGH TUESDAY EVENING RESULTING IN
MINOR TO LOCALLY MODERATE HEATRISK. THIS LEVEL OF HEAT
PRIMARILY AFFECTS THOSE WHO ARE SENSITIVE TO HEAT.
- COLD WATER TEMPERATURES POSE A HIGH RISK FOR COLD WATER SHOCK
AND HYPOTHERMIA. WEAR A LIFE JACKET IF RECREATING ON OR NEAR THE
WATER.
- WIDESPREAD SHOWERS, CHANCES FOR THUNDERSTORMS, AND GUSTY WINDS
TUESDAY NIGHT THROUGH WEDNESDAY. GUSTY WINDS MAY LEAD TO
CHOPPY LAKES, STRONG CROSS WINDS, AND ISOLATED AREAS OF
BLOWING DUST WHERE PRECIPITATION IS LIMITED.
SYNOPSIS
ISOLATED DRY THUNDERSTORMS AND GUSTY WINDS ARE EXPECTED TUESDAY
EVENING THROUGH EARLY WEDNESDAY MORNING. TEMPERATURES TURN
COOLER WEDNESDAY, WITH STRONG WEST TO SOUTHWEST WINDS,
AND WIDESPREAD SHOWERS. BREEZY WINDS AND CHANCES FOR MOUNTAIN
SHOWERS AND THUNDERSTORMS LINGER THURSDAY THROUGH SATURDAY. SOME
FROST IS POSSIBLE TOWARD THE END OF THE WEEK INTO THE WEEKEND.
DISCUSSION
TUESDAY NIGHT THROUGH THURSDAY: AN AMPLIFIED UPPER-LEVEL RIDGE IS
CURRENTLY IN PLACE OVER THE INLAND NORTHWEST AS AN UPPER-LEVEL
CLOSED LOW APPROACHES THE PACIFIC NORTHWEST. MODELS HAVE GENERALLY
COME INTO BETTER AGREEMENT ON THE TRAJECTORY OF THE UPPER-LEVEL LOW
AS IT TAKES ON A NEGATIVE TILT AND MOVES INTO OREGON LATE TONIGHT.
AHEAD OF THE LOW, THE COMBINATION OF FAVORABLE UPPER-LEVEL
DIFFLUENCE AND MOISTURE ADVECTING INTO THE INLAND NORTHWEST WILL
SUPPORT SHOWER AND THUNDERSTORM DEVELOPMENT TONIGHT INTO EARLY
WEDNESDAY MORNING. MODELS ARE SHOWING ELEVATED INSTABILITY (MUCAPE
BETWEEN 200-600 J/KG) OVERTOP A VERY DRY BOUNDARY LAYER, WHICH
BRINGS THE RISK OF DRY LIGHTNING AND GUSTY OUTFLOW WINDS.
THE LOW WILL MOVE INTO EASTERN OREGON WEDNESDAY MORNING AND SHIFT
NORTHEAST INTO EASTERN WASHINGTON AND NORTH IDAHO WEDNESDAY AFTERNOON
AND EVENING. PRECIPTIATION WILL INCREASE IN COVERAGE LATER WEDNESDAY
MORNING THROUGH THE AFTERNOON. THE HEAVIEST PRECIPITATION TOTALS ARE
EXPECTED ACROSS THE MOUNTAINS WHERE 25TH TO 75TH PERCENTILE 24 HOUR
AMOUNTS BETWEEN 0.30 TO 1.30 INCHES. TOTALS ACROSS THE LOWLANDS VARY
DEPENDING ON THE TRACK OF THE LOW WITH 25TH TO 75TH PERCENTILE
AMOUNTS BETWEEN 0.05 INCHES TO 0.30 INCHES FOR THE COLUMBIA BASIN
INTO THE SPOKANE AREA AND NORTHERN PALOUSE. 25TH TO 75TH PERCENTILE
PRECIPITATION AMOUNTS ARE LOWEST ACROSS THE PALOUSE AND L-C VALLEY
AT 0 TO 0.10 INCHES.
ADDITIONALLY, THE PASSAGE OF THE LOW WILL TIGHTEN CROSS-CASCADE
PRESSURE GRADIENTS WEDNESDAY AFTERNOON AND EVENING. MODELED SURFACE
PRESSURE GRADIENTS FOR YKM-YQL (+17 TO +24MB) AND PDX-GEG (+9 TO
+14MB) GRADIENTS SUGGEST THE POTENTIAL FOR STRONGER WESTERLY WINDS
ACROSS MUCH OF THE INLAND NORTHWEST. WINDS WILL BEGIN TO INCREASE
WEDNESDAY MORNING AND ARE EXPECTED TO PEAK BETWEEN 10 AM AND 5 PM
AND GRADUALLY DECREASE THROUGH THE EVENING. THERE IS HIGH CONFIDENCE
FOR WIND GUSTS GREATER THAN 45 MPH FROM THE LEE OF THE CASCADES
THROUGH THE COLUMBIA BASIN AND INTO THE PALOUSE AND SPOKANE AREA.
THE STRONGEST WINDS WILL BE FELT ACROSS THE BLUE MOUNTAINS WITH HIGH
CONFIDENCE FOR GUSTS GREATER THAN 55 MPH. THESE WINDS WILL BE STRONG
ENOUGH TO RESULT IN SCATTERED TREE DAMAGE AND POWER OUTAGES, STRONG
CROSS WINDS, AND CHOPPY LAKE CONDITIONS. IF THE COLUMBIA BASIN
PRECIPITION TOTALS ARE BELOW 0.10 INCHES, PATCHY BLOWING DUST WILL
ALSO BE A CONCERN. HOWEVER, THERE IS A 70% CHANCE FOR GREATER THAN
0.10 INCHES, SO CONFIDENCE IN THIS OCCURRING IS LOW. LIGHT MOUNTAIN
SHOWERS WILL PERSIST THROUGH THURSDAY AS THE REGION TRANSITIONS INTO
A BRIEF PERIOD OF WEAK RIDGING.
FRIDAY THROUGH MONDAY: MODELS SHOW A BROAD UPPER-LEVEL TROUGH IN THE
NORTHEAST PACIFIC WITH EMBEDDED WAVES MOVING INTO THE REGION FRIDAY
AND SATURDAY BEFORE THE LOW DIVES INTO THE PNW SATURDAY INTO SUNDAY.
DIFFERENCES IN THE SPECIFICS OF THESE SYSTEMS INTRODUCES A GOOD
AMOUNT OF UNCERTAINTY IN THE EXACT FORECAST, BUT THE MAIN MESSAGE IS
THAT THIS WEEKEND LOOKS TO BE COOLER WITH PERIODIC PRECIPITATION.
THE NBM IS GIVING THE CASCADES A 60% CHANCE AND GREATER FOR 1 INCH
OF SNOWFALL. SUNDAY MORNING WILL ALSO NEED TO BE MONITORED FOR FROST
POTENTIAL WITH A 50% OR GREATER CHANCE FOR TEMPERATURES BELOW 36F
ACROSS MUCH OF THE BASIN, NORTHERN VALLEYS, SPOKANE/CDA AREA, AND
THE PALOUSE. /VMT
AVIATION
18Z TAFS: UPPER-LEVEL RIDGE IS AMPLIFYING THIS AFTERNOON IN
RESPONSE TO AN APPROACHING LOW PRESSURE SYSTEM. INCREASING MID
AND UPPER LEVEL MOISTURE IS BRINGING AN INCREASE IN CLOUDS
AHEAD OF THIS SYSTEM. HIGH RESOLUTION MODELS ARE SHOWING SHOWER
AND ISOLATED THUNDERSTORMS MOVING INTO EASTERN WASHINGTON AND
NORTH IDAHO FROM THE SOUTH POTENTIALLY AS EARLY AS 04Z, THOUGH
CONFIDENCE INCREASES AFTER 06Z. THE BEST CHANCES FOR
THUNDERSTORMS EXISTS FOR THE CASCADES AND FAR NORTHEAST
WASHINGTON BETWEEN 06-12Z WITH CONFIDENCE NOT HIGH ENOUGH TO
INCLUDE IN ANY TAF SITES. SHOWER COVERAGE INCREASES LATER
WEDNESDAY AFTERNOON WITH CEILINGS AT KGEG/KSFF/KCOE TRENDING
TOWARD 3K FEET NEAR THE END OF THE TAF PERIOD.
WINDS ARE EXPECTED TO INCREASE MID WEDNESDAY MORNING AHEAD OF A
COLD FRONT WITH SOUTH-SOUTHWEST WINDS 20-25 KNOTS AND GUSTS UP
TO 30 KNOTS THROUGH 18Z. PEAK WINDS ARE EXPECTED BETWEEN 18Z
WEDNESDAY AND 00Z THURSDAY WITH WEST TO SOUTHWEST GUSTS 30-45
KNOTS FROM THE LEE OF THE CASCADES THROUGH THE COLUMBIA BASIN
AND THE PALOUSE.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
HIGH CONFIDENCE FOR VFR CONDITIONS FOR ALL TAF SITES. LOW
CONFIDENCE IS SHOWERS AND T-STORMS IMPACTING TAF SITES BETWEEN
04-12Z WEDNESDAY. BEST CHANCES NEAR KEAT, WITH SOME ISOLATED
ACTIVITY POSSIBLE AT OTHER TAF SITES.
-----------------------
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 53 65 43 64 41 62 / 10 80 50 0 0 10
COEUR D'ALENE 53 64 44 62 42 59 / 10 90 80 0 10 20
PULLMAN 50 62 41 61 40 59 / 10 70 40 0 0 0
LEWISTON 56 68 47 68 45 67 / 10 50 20 0 0 0
COLVILLE 49 69 36 67 35 64 / 20 90 70 0 0 10
SANDPOINT 52 66 41 61 40 59 / 10 90 90 0 10 20
KELLOGG 53 66 42 59 41 59 / 10 90 90 20 10 10
MOSES LAKE 52 68 43 69 40 67 / 10 90 10 0 0 0
WENATCHEE 56 65 48 67 44 65 / 10 90 10 0 0 0
OMAK 55 70 42 69 40 66 / 20 100 10 0 0 0
OTX WATCHES/WARNINGS/ADVISORIES
WA...WIND ADVISORY FROM 8 AM TO 11 PM PDT WEDNESDAY FOR NORTHEAST
MOUNTAINS.
WIND ADVISORY FROM 5 AM TO 11 PM PDT WEDNESDAY FOR MOSES LAKE
AREA-SPOKANE AREA-UPPER COLUMBIA BASIN-WASHINGTON PALOUSE-
WATERVILLE PLATEAU-WENATCHEE AREA.
HIGH WIND WARNING FROM 5 AM TO 11 PM PDT WEDNESDAY FOR LOWER
GARFIELD AND ASOTIN COUNTIES-NORTHEAST BLUE MOUNTAINS.
ID...WIND ADVISORY FROM 8 AM TO 11 PM PDT WEDNESDAY FOR CENTRAL
PANHANDLE MOUNTAINS-NORTHERN PANHANDLE.
WIND ADVISORY FROM 5 AM TO 11 PM PDT WEDNESDAY FOR COEUR
D'ALENE AREA-IDAHO PALOUSE-LEWIS AND SOUTHERN NEZ PERCE
COUNTIES-LEWISTON AREA.
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