212  
FXUS63 KARX 131150  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
650 AM CDT THU AUG 13 2020  
   
SHORT TERM
 
(TODAY AND TONIGHT)  
ISSUED AT 335 AM CDT THU AUG 13 2020  
 
SKIES WERE PARTLY TO MOSTLY CLOUDY EARLY THIS MORNING, WITH  
TEMPERATURES RANGING FROM THE MID 50S TO UPPER 60S. A FEW SHOWERS  
AND ISOLATED STORMS ASSOCIATED WITH AN AREA OF STRONGER 925 MB  
MOISTURE TRANSPORT WERE MOVING ACROSS TAYLOR AND CLARK COUNTIES  
IN FAR NORTH-CENTRAL WISCONSIN.  
 
SHOWERS/STORMS ACROSS NORTH-CENTRAL WISCONSIN SHOULD DIMINISH THIS  
MORNING AS MOISTURE TRANSPORT JUST TO OUR NORTHWEST DECREASES. FOR  
THE REST OF THE DAY, STRONGER MOISTURE TRANSPORT, INSTABILITY, AND  
SHORTWAVE ENERGY STAY TO OUR NORTHWEST, AS DO HIGHER PRECIPITATION  
CHANCES. LOCALLY, MODELED SOUNDINGS SHOW A BIT OF CAPPING  
DEVELOPING, SO WITHOUT STRONGER FORCING THIS WOULD TEND TO FAVOR DRY  
WEATHER. A STRAY SHOWER OR STORM COULD PERHAPS INTRUDE FROM THE  
WEST, BUT RIGHT NOW THIS THREAT LOOKS LOW AND HAVE TRENDED THINGS  
DRY. CURRENT CLOUD COVER MIGHT THIN LATER THIS MORNING AND ALLOW FOR  
SOME SUNSHINE, BUT ADDITIONAL CUMULUS COULD FORM THIS AFTERNOON  
GIVEN STEEPENING LAPSE RATES. HIGHS ARE EXPECTED TO REACH THE 80S,  
THOUGH MORE PERSISTENT CLOUD COVER COULD KEEP SOME AREAS IN THE  
UPPER 70S.  
   
LONG TERM
 
(FRIDAY THROUGH WEDNESDAY)  
ISSUED AT 335 AM CDT THU AUG 13 2020  
 
NEXT TIME PERIOD TO WATCH FOR PRECIPITATION LOOKS TO BE FRIDAY  
MORNING, AS A WEAKENING LINE OF SHOWERS/STORMS PROGRESSES ACROSS  
MINNESOTA. GUIDANCE REALLY DIMINISHES THIS BEFORE REACHING OUR AREA,  
LIKELY DUE TO THE LESS FAVORABLE INSTABILITY AND LACK OF STRONG  
MOISTURE TRANSPORT COMPARED TO LOCATIONS BACK TO OUR WEST. WITH NO  
STRONG SIGNAL FOR PRECIPITATION, HAVE CONFINED SMALL POPS TO THE  
FAR WEST FRIDAY MORNING, WITH THE AFTERNOON LOOKING DRIER. HIGHS  
COULD BE A TOUCH WARMER THAN THURSDAY, WITH SOME LOCATIONS  
APPROACHING THE UPPER 80S. ATTENTION THEN TURNS TO AN APPROACHING  
COLD FRONT. DEEP SHEAR IS NOT VERY IMPRESSIVE WITH THIS FEATURE  
(SUB-30 KT 0-6 KM BULK SHEAR IN THE GFS/ECMWF/CANADIAN, THOUGH THE  
NAM IS A HIGHER OUTLIER), BUT INSTABILITY BUILDS IN SOUTHERLY,  
MOIST FLOW AHEAD OF THE FRONT FRIDAY. LATEST GUIDANCE DOESN'T HAVE  
THE FRONT ARRIVING IN OUR AREA UNTIL ABOUT 04Z SATURDAY, HOWEVER,  
BY WHICH TIME INSTABILITY IS FORECAST TO HAVE REALLY WANED.  
COULDN'T TOTALLY RULE OUT A STRONGER STORM OR TWO JUST AS THE  
STORMS REACH THE AREA, BUT THE DIMINISHING INSTABILITY IS NOT SO  
FAVORABLE FOR SEVERE WEATHER. LATEST SPC OUTLOOKS ARE  
GEOGRAPHICALLY SIMILAR TO THIS THINKING, WITH THE 06Z DAY 2  
OUTLOOK SLIGHT RISK MAINLY TO OUR NORTHWEST WHERE THE FRONT  
ARRIVES EARLIER AND THE MARGINAL RISK ACROSS WESTERN/NORTHWESTERN  
PORTIONS OF THE AREA.  
 
THE FRONT PROGRESSES THROUGH THE AREA SATURDAY MORNING, EXITING TO  
OUR SOUTHEAST BY EARLY AFTERNOON. IF THIS EXIT ENDS UP BEING A  
LITTLE LATER INTO THE AFTERNOON, THERE COULD BE POTENTIAL FOR A FEW  
STRONGER STORMS ACROSS FAR SOUTHWEST WI/FAR NORTHEAST IOWA, BUT  
RIGHT NOW MOST GUIDANCE SEEMS TO FAVOR THE BEST INSTABILITY RECOVERY  
OCCURRING TO THE SOUTHEAST OF OUR AREA.  
 
COOLER, DRIER NORTHWEST FLOW THEN BUILDS IN SUNDAY THROUGH EARLY  
NEXT WEEK. HIGHS ARE EXPECTED TO BE IN THE 70S, WITH LOWS IN THE  
50S. RAIN CHANCES COULD RETURN MID-WEEK AS A STRONGER SHORTWAVE  
MOVES THROUGH IN NORTHWEST FLOW, THOUGH PREDICTABILITY IS LOW THIS  
FAR OUT.  
 

 
   
AVIATION
 
(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)  
ISSUED AT 637 AM CDT THU AUG 13 2020  
 
SATELLITE IMAGERY AND RADAR SHOW WEATHER DISTURBANCES PASSING TO  
THE NORTH AND SOUTH OF THE TAF SITES TODAY. THUS...WE ARE LOOKING  
A VARIABLE CLOUD COVER, BUT GENERALLY DRY CONDITIONS. SOME PATCHY  
MVFR CONDITIONS DID DEVELOP OVERNIGHT AND THERE IS A BROAD AREA OF  
IFR CONDITIONS OVER WESTERN MN. THE MVFR CONDITIONS HAVE BROKEN  
UP WITH SCATTERED CLOUDS FL040-050. SCT-BKN CLOUD FL050-150  
THROUGH TODAY AND THIS EVENING. AS THE LOW LEVEL WINDS DECREASING  
AGAIN TONIGHT, SHOULD SEE SOME PATCHES OF MVFR/IFR CONDITIONS RE-  
DEVELOP AND FAVOR AFTER 08-10Z. SOUTH WINDS 6 TO 12KTS TODAY AND 4  
TO 8 KTS TONIGHT.  
 

 
   
ARX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
MN...NONE.  
IA...NONE.  

 
 

 
 
SHORT TERM...LEE  
LONG TERM...LEE  
AVIATION...ZAPOTOCNY  
 
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