762  
FXUS66 KOTX 312225  
AFDOTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SPOKANE WA  
325 PM PDT MON MAR 31 2025  
   
SYNOPSIS  
 
SHOWERS WILL CONTINUE ACROSS THE REGION FOR MONDAY. ISOLATED  
THUNDERSTORMS ARE POSSIBLE MONDAY AFTERNOON. COOL AND UNSETTLED  
WEATHER PATTERN WILL PERSIST THROUGH MUCH OF THE WEEK WITH A  
WARMING AND DRYING TREND BY THE WEEKEND.  
 
 
   
DISCUSSION  
 
TONIGHT THROUGH WEDNESDAY NIGHT: UNSETTLED WEATHER WILL CONTINUE.  
THIS AFTERNOON REGIONAL RADAR SHOWS SHOWERS SCATTERED THROUGHOUT  
THE REGION, BUT THERE ARE SOME FOCUSING MECHANISMS FOR THESE  
SHOWERS. IN THE LARGE SCALE LOW PRESSURE IS CENTERED OFF THE COAST  
AND THAT BROAD FEATURE WILL SHIFT INLAND OVERNIGHT INTO TUESDAY  
MORNING. A DEFORMATION AXIS AROUND ITS EAST TO NORTH SIDE, FROM  
IDAHO TO NORTHEAST WA AND BACK SOUTHWEST INTO THE DEEPER BASIN,  
WILL GRADUALLY PIVOT EASTWARD THROUGH THAT SAME PERIOD. ANYWHERE  
ALONG THAT FEATURE AND UNDER THE TROUGH THERE WILL BE A RISK FOR  
SHOWERS AND MAYBE SOME ISOLATED T-STORMS.  
 
SHOWERS HAVE BEEN LOCALLY FOCUSED OVER SOUTHEAST WA AND LOWER ID  
WITH AN UPPER IMPULSE SLIDING BY. THESE WILL CONTINUE TO TRACK  
EAST-NORTHEAST THROUGH THIS EVENING, WITH OTHER WAVE POTENTIALLY  
SLIPPING BY THE BLUES AND CAMAS PRAIRIE AND L-C VALLEY ON ITS  
HEELS. ANOTHER FOCAL POINT FOR SHOWERS WILL BE AROUND AROUND THE  
NORTHERN COLUMBIA BASIN WEST-SOUTHWEST TOWARD THE WATERVILLE  
PLATEAU/WESTERN BASIN. THAT FEATURE IS EXPECTED TO LINGER THERE  
THROUGH THE EVENING, GRADUALLY MIGRATING EAST ACROSS THE UPPER  
COLUMBIA BASIN AND SPOKANE/C'DA OVERNIGHT INTO TUESDAY MORNING.  
 
AS WE HEAD INTO TUESDAY AFTERNOON, THE UPPER TROUGH AND CONTINUED  
INSTABILITY WILL ALLOW FOR THE BUBBLING UP OF SCATTERED SHOWERS  
AGAIN IN THE HEATING OF THE DAY. THESE WILL BE KIND OF HIT-AND-  
MISS AGAIN TOO, BUT A SECONDARY UPPER WAVE COMING IN FROM THE  
NORTHWEST LATER IN THE AFTERNOON INTO TUESDAY NIGHT WILL ALLOW  
MORE MORE FOCUSED SHOWER CHANCES. THEY WILL FIRST BE MORE AROUND  
THE CASCADES, CENTRAL WA AND THEN MIGRATE TOWARD EASTERN WA AND  
NORTH ID IN THE EVENING AND ON THROUGH IDAHO BY LATE EVENING INTO  
THE OVERNIGHT.  
 
SOME SHOWERS BETWEEN THIS AFTERNOON INTO TUESDAY COULD BE LOCALLY  
HEAVY. SOME HAVE BEEN HEAVY ENOUGH TO CAUSE WET-BULB COOLING  
ENOUGH TO MIX SOME SNOW DOWN. SO THAT IS SOMETHING TO WATCH OUT  
FOR. ADDITIONALLY ISOLATED EMBEDDED T-STORMS ARE POSSIBLE AND  
COULD BRING LOCALLY HEAVY DOWNPOURS, GUSTY WINDS AND SMALL HAIL.  
 
SOME OF THAT MAY COME IN THE FORM OF A RAIN/SNOW MIX IN THE  
LOWLANDS OVERNIGHT/EARLY TUESDAY. MEANWHILE IN THE MOUNTAINS,  
INCLUDING THE PASSES, SNOW WILL BE MORE LIKELY. ACCUMULATIONS OF  
1-3 INCHES WILL BE POSSIBLE, BUT DURING THE DAYTIME HOURS IT WILL  
BE HARDER FOR THOSE ACCUMULATIONS TO STICK. SO IMPACTS ARE  
EXPECTED TO BE LIMITED.  
 
HEADING INTO WEDNESDAY WE WILL REMAIN UNDER THE INFLUENCE OF AN  
UPPER TROUGH, BUT MORESO IN A WEST-NORTHWEST FLOW SECTOR OF THE  
TROUGH. SHOWER CHANCES WILL CONTINUE AROUND THE CASCADES AND THE  
EASTERN MOUNTAINS ZONES, WITH ADDITIONAL CHANCES DEVELOPING IN THE  
AFTERNOON ACROSS THE EAST THIRD OF WA AND LOWER ID TOO. IF ANY OF  
THIS FALLS IN THE LOWLANDS THERE WILL BE A POTENTIAL RAIN/SNOW  
MIX, GIVEN THE COOLER ATMOSPHERE UNDER THE TROUGH.  
 
TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW SEASONAL NORMS,  
WITH HIGHS IN THE UPPER 40S AND 50S AND LOWS IN THE UPPER 20S AND  
30S.  
 
THURSDAY THROUGH MONDAY: THE INLAND NW WILL BE ON THE BACKSIDE OF  
A DEPARTING TROUGH THURSDAY INTO FRIDAY BEFORE UPPER-LEVEL  
RIDGING SETTLES IN OVER THE WEEKEND. THERE WILL BE ENOUGH  
INSTABILITY LINGERING OVER THE REGION THURSDAY AFTERNOON TO KEEP A  
MENTION OF SHOWERS YET DRIER AIR CONTINENTAL AIR COMING IN THE  
LOWER LEVELS WILL KEEP RAINFALL AMOUNTS VERY LIGHT. BULK OF THE  
SHOWERS WILL ALSO FOCUS OVER THE IDAHO PANHANDLE AND EASTERN  
REACHES OF WA GIVEN THE NORTHWESTERLY FLOW PATTERN. 70% OF THE  
ENSEMBLES ARE DRY BY FRIDAY WITH 30% HOLDING ON TO A GLIMMER OF  
HOPE FOR A FEW LAST CONVECTIVE SHOWERS. FORECAST LEANS TOWARD THE  
DRIER SCENARIO. CONFIDENCE INCREASES BY THE WEEKEND FOR HIGH  
PRESSURE TO BUILD OVER THE NW DELIVERING A DRY, WARMING TREND.  
HIGH TEMPERATURES WILL BE REBOUNDING FROM THE 50S AND 60S ON  
THURSDAY TO THE 60S AND 70S OVER THE WEEKEND. OUR MAIN UNCERTAINTY  
FOR THE FRI-SUN TIME-FRAME REVOLVES AROUND THE AMOUNT OF DRY,  
CONTINENTAL AIR THAT BLEEDS IN FROM THE NORTH PRIOR TO THE RIDGE.  
THERE IS STILL MODERATE SPREAD BETWEEN THE ENS/GEPS AND GEFS MEANS  
TO WHICH RANGE THE DEWPOINTS WILL LOWER TO. IF THEY LOWER INTO  
THE LOWER 20S OR UPPER TEENS, THIS WOULD RESULT IN SOME DRY  
RELATIVE HUMIDITIES OVER THE WEEKEND AND ELEVATED FIRE WEATHER  
CONCERNS IN REGARDS TO BURN PILES SPREADING INTO DRY GRASSES FROM  
LAST SUMMER THOUGH WE ARE NOT LOOKING AT MUCH WIND. IF THEY HOLD  
IN THE UPPER 20S TO LOWER 30S, HUMIDITY LEVELS WILL BE HIGHER  
(CLOSER TO 30%) WHICH LOWERS THE CONCERN FOR FIRE SPREAD. OVERALL,  
VERY MINIMAL IMPACTS IN THE GRAND SCHEME BUT SOMETHING TO MONITOR  
IF LOOKING TO BURN. THE OTHER IMPACT WOULD BE OVERNIGHT LOWS. A  
DRIER SCENARIO WOULD ALLOW STRONG RADIATIONAL COOLING AND LOWS IN  
THE 20S TO 30S WHILE A "HIGHER DEWPOINT" SCENARIO WOULD FAVOR LOWS  
MORE IN THE 30S. AS SPRING FEVER SETS IN FOR PLANTING...KEEP THIS  
IN MIND.  
 
BY MONDAY, THE RIDGE LOOKS TO TAKE A BLOW FROM AN INCOMING TROF.  
70% CHANCE MOST OF THE PRECIPITATION WILL BE DEFLECTED WEST OF  
THE CASCADES AND INTO BC BUT THIS WILL LIKELY BRING INCREASING  
CLOUDS AND INCREASED WINDS. THE AIR MASS WILL REMAIN MILD WITH  
MONDAY LOOKING TO BE ONE OF THE WARMEST DAYS OF THE PERIOD,  
ESPECIALLY WITH THE INCREASED WINDS AND BETTER MIXING. /SB  
 
 
   
AVIATION  
 
00Z TAFS: BANDS OF SHOWERS WILL CONTINUE TO IMPACT THE INLAND NW.  
SOME SHOWERS WILL REMAIN FOCUSED AROUND SOUTHEAST WA INTO CENTRAL  
ID THIS EVENING, THEN DECREASE. EMBEDDED T-STORMS WITH LIGHTNING  
POSSIBLE FROM 21-04Z. ADDITIONAL SHOWERS WILL BE FOCUSED AROUND  
THE NORTHERN AND WESTERN COLUMBIA BASIN, EXPANDING EASTWARD  
OVERNIGHT INTO TUESDAY AM, POTENTIALLY REACHING GEG/SFF TOWARD  
12-15Z. THEN THE HEATING OF THE DAY WILL BRING A THREAT OF  
ISOLATED TO SCATTERED SHOWERS TUESDAY PM. ANY HEAVIER SHOWERS  
COULD RESULT IN PRECIPITATION TURNING TO SNOW OR AT LEAST A  
RAIN/SNOW MIX. PERIODS OF MVFR CEILINGS FOR EASTERN WA AND ID  
THROUGH EARLY EVENING, THEN VFR. THEN HEADING INTO TUESDAY AM  
(10-14Z) MODELS SHOW AN EXPANDING MVFR STRATUS DECK OVER THE EAST  
WA AND NORTH ID, WITH A SOME RISK FOR IFR CONDITIONS DEVELOPING.  
GEG/SFF/COE HAVE THE BEST CHANCES OF MVFR.  
 
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: MODERATE  
UNCERTAINTY FOR CIGS IN EASTERN WA AND NORTH ID. 40-70% CONFIDENCE  
IN MVFR CONDITIONS AT GEG/SFF/COE/PUW IN THE AFTERNOON. MODERATE  
CONFIDENCE IN MVFR CONDITIONS TOWARD TUESDAY AM NEAR GEG/SFF/COE.  
LOW CONFIDENCE IN MVFR CONDITIONS AT OTHER TAF SITES. LOW  
CONFIDENCE IN IFR CONDITIONS AT GEG/SFF/COE. LOW CONFIDENCE  
IN -TSRA AT TAF SITES, BUT BEST RISK BEFORE 03Z TUESDAY OVER SE  
WA/LOWER ID.  
 
-----------------------  
CONFIDENCE DESCRIPTORS:  
LOW - LESS THAN A 30 PERCENT CHANCE  
MODERATE - 30 TO 70 PERCENT CHANCE  
HIGH - GREATER THAN A 70 PERCENT CHANCE  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
SPOKANE 35 49 34 51 34 52 / 30 40 20 20 20 40  
COEUR D'ALENE 34 47 34 49 32 50 / 60 50 20 20 30 60  
PULLMAN 32 47 34 47 32 49 / 20 20 10 20 10 50  
LEWISTON 37 54 39 54 37 55 / 20 20 10 20 10 30  
COLVILLE 34 50 31 52 32 53 / 40 30 20 40 30 40  
SANDPOINT 35 45 34 46 33 49 / 60 50 30 40 50 80  
KELLOGG 35 44 37 44 34 45 / 60 60 30 50 20 80  
MOSES LAKE 35 57 33 57 33 60 / 30 20 10 10 0 10  
WENATCHEE 37 56 36 56 35 56 / 50 10 0 10 0 10  
OMAK 37 58 34 57 33 58 / 60 30 20 20 10 10  
 
 
   
OTX WATCHES/WARNINGS/ADVISORIES  
 
ID...NONE.  
WA...NONE.  
 
 
 
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