566  
FXUS66 KOTX 172358  
AFDOTX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SPOKANE WA  
458 PM PDT TUE SEP 17 2019  
   
SYNOPSIS
 
 
BANDS OF RAIN WILL SPREAD ACROSS WASHINGTON INTO THE IDAHO  
PANHANDLE OVERNIGHT. WEDNESDAY WILL BE COOL AND SHOWERY WITH  
AFTERNOON TEMPERATURES IN THE 50S AND 60S WHICH IS NEARLY 15  
DEGREES BELOW AVERAGE. PERIODS OF SHOWERS WILL LINGER OVER THE  
IDAHO PANHANDLE THURSDAY AND FRIDAY. OUR BEST SHOT OF A DRY DAY  
REGION-WIDE WILL BE SATURDAY BEFORE THE ARRIVAL OF ANOTHER  
MOIST FRONTAL SYSTEM ON SUNDAY.  
 

 
   
DISCUSSION
 
 
TONIGHT: BANDS OF RAIN WILL MARCH ACROSS EASTERN WASHINGTON TOWARD  
THE IDAHO PANHANDLE THIS EVENING. RAIN BANDS WILL GENERALLY WEAKEN  
AS THEY MOVE EAST THIS EVENING AS PRECIPITATION ENCOUNTERS AND  
UPPER LEVEL HIGH PRESSURE OVER MONTANA. AFTER MIDNIGHT OUR FRONTAL  
SYSTEM STALLING NEAR THE WASHINGTON-IDAHO BORDER SHOULD  
REGENERATE WIDESPREAD LIGHT TO MODERATE PRECIPITATION ACROSS THE  
PANHANDLE AND EASTERN THIRD OF WASHINGTON. THE MODELS ARE IN GOOD  
AGREEMENT THAT AN UPPER LOW PIVOTING INLAND WILL SUPPLYING  
SUFFICIENT MOISTURE AND LIFT TO REGENERATE FRONTAL PRECIPITATION  
THAT WILL PERSIST INTO WEDNESDAY.  
 
WEDNESDAY: BANDS OF MORNING RAIN WILL GIVE WAY TO CLUSTERS OF  
SHOWERS THROUGH THE AFTERNOON AND EVENING. PLACES THAT EXPERIENCE  
SUNBREAKS IN THE AFTERNOON WILL HAVE A CHANCE OF AFTERNOON  
THUNDERSTORMS. AT THIS TIME, IT LOOKS LIKE THE NORTH IDAHO  
PANHANDLE AND MUCH OF NORTHEAST WASHINGTON WILL BE CLOUDY FOR MUCH  
OF THE DAY WITH HIGHS STRUGGLING TO GET OUT OF THE 50S. THE GFS  
AND NAM SUGGEST ENOUGH SUNBREAKS AND SURFACE BASED INSTABILITY IN  
THE COLUMBIA BASIN AND CENTRAL WASHINGTON FOR A FEW EMBEDDED  
THUNDERSTORMS CAPABLE OF BRIEF HEAVY DOWNPOURS.  
 
THURSDAY: CENTRAL WASHINGTON AND THE COLUMBIA BASIN SHOULD HAVE A  
DAY WITHOUT SHOWERS AS OUR SLOW MOVING UPPER TROUGH MIGRATES INTO  
EASTERN IDAHO AND MONTANA. THE IDAHO PANHANDLE AND SOUTHEAST  
WASHINGTON CAN EXPECT MORE RAIN SHOWERS WITH THE BEST CHANCES  
DURING THE AFTERNOON AND EARLY EVENING. A FEW OF THE STRONGER  
CELLS WILL BE CAPABLE OF BRIEF HEAVY DOWNPOURS AND CLOUD TO GROUND  
LIGHTNING. /GKOCH  
 
FRIDAY NIGHT AND SATURDAY: WITH THE RIDGE CURRENTLY OVER  
NORTHWESTERN US, THE REGION CONTINUES TO BE WARM AND DRIER THAN DAYS  
PRIOR. HOWEVER, THERE IS STILL A CHANCE FOR LIGHT, ISOLATED SHOWERS  
IN THE IDAHO PANHANDLE THROUGH THE DAY SATURDAY, BUT REMAINING DRY  
FOR EASTERN WASHINGTON. LIGHT WINDS WITH TEMPERATURES CONTINUING TO  
REMAIN COOLER THAN SEASONAL NORMALS. HIGH TEMPERATURES WILL REACH  
THE MID-60S TO LOW-70S, WHEN MUCH OF THE REGION'S NORMS ARE IN THE  
MID- TO UPPER-70S.  
 
SUNDAY THROUGH TUESDAY: FOLLOWING A DRY FEW DAYS WITH THE RIDGE, A  
TROUGH BEGINS TO MOVE INTO THE NORTHWEST BRINGING THE NEXT ROUND OF  
PRECIPITATION. THE MODELS ARE BEGINNING TO SHOW MORE AGREEMENT WITH  
THE ARRIVAL OF PRECIPITATION TO OCCUR EARLY MORNING SUNDAY AT THE  
CASCADES, BUT THERE IS STILL TIME FOR THINGS TO CHANGE. HOWEVER, THE  
MODELS ALSO DIFFER IN THE PROGRESSION AND INTENSITY. THERE IS NO  
AGREEMENT WHETHER THIS INCOMING PRECIPITATION STAYS CONSOLIDATED OR  
SPLITS AS IT MOVES THROUGH THE REGION. FORECAST CONFIDENCE CONTINUES  
TO REMAIN LOW, BUT IT DOES LOOK LIKE SUNDAY/MONDAY WILL BE AN  
UNSETTLED START TO THE WEEK. JS  
 

 
   
AVIATION
 
 
00Z TAFS: BAND OF LIGHT RAIN IS MOVING IN TO EASTERN WASHINGTON  
THIS AFTERNOON AND EVENING. THE MODELS SEEM TO HAVE SPED UP THE  
TIMING OF THE PRECIPITATION. THE INITIAL ROUND OF RAIN WILL BE  
RELATIVELY LIGHT WITH CIGS REMAINING ABOVE 4K FT. THERE WILL BE A  
BRIEF BREAK AND THEN ANOTHER ROUND OF WIDESPREAD RAIN AFT 07Z FOR  
LWS/PUW AND INTO GEG/SFF/COE BY 09Z. RAIN WILL CONTINUE THROUGH  
THE MORNING HOURS AND BY AFTERNOON THERE WILL BE A THREAT OF  
THUNDERSTORMS ACROSS PORTIONS OF CENTRAL WA. BROUGHT IN SOME MVFR  
CIGS THROUGH THE OVERNIGHT HOURS INTO THE MORNING, BUT CIGS SHOULD  
BEGIN TO LIFT BY LATE MORNING.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
SPOKANE 48 58 45 63 48 66 / 60 80 30 10 10 10  
COEUR D'ALENE 48 56 44 63 48 65 / 40 80 30 20 20 30  
PULLMAN 48 60 45 62 46 65 / 50 80 40 40 20 20  
LEWISTON 54 64 50 69 51 71 / 70 70 40 40 30 10  
COLVILLE 45 59 41 70 46 72 / 70 90 30 10 10 10  
SANDPOINT 46 54 43 64 47 64 / 40 80 30 20 20 30  
KELLOGG 48 56 44 60 46 62 / 50 80 40 50 30 50  
MOSES LAKE 47 66 46 73 50 74 / 50 40 30 10 0 0  
WENATCHEE 49 63 48 69 54 72 / 50 60 20 10 0 10  
OMAK 50 62 46 68 52 73 / 80 70 20 10 0 10  
 

 
   
OTX WATCHES/WARNINGS/ADVISORIES
 
 
ID...NONE.  
WA...NONE.  
 

 
 

 
 
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