544  
FXUS63 KARX 191752  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
1252 PM CDT WED AUG 19 2026  
   
KEY MESSAGES  
 
- DRY AND PLEASANT TODAY.  
 
- THUNDERSTORM POTENTIAL RETURNS THURSDAY EVENING INTO FRIDAY  
MORNING WITH THE MAIN HAZARD BEING LIGHTNING.  
 
- SEASONAL TEMPERATURES IN THE 70S TO LOWER 80S ARE FORECAST EACH  
AFTERNOON OVER THE NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 1240 PM CDT WED AUG 19 2026  
 
THIS AFTERNOON TO THURSDAY MORNING: DRY AND PLEASANT CONDITIONS  
 
A COOLER, DRIER AIRMASS WILL REMAIN IN PLACE THROUGH THE REST OF  
TODAY INTO THURSDAY MORNING OVER THE UPPER MIDWEST. PLEASANT  
CONDITIONS ARE FORECAST DURING THIS TIME FRAME WITH LIGHT WINDS  
AND MOSTLY CLEAR SKIES. LIGHT WINDS AND CLEAR SKIES TONIGHT MAY  
SUPPORT THE FORMATION OF SOME PATCHY FOG, ESPECIALLY IN THE  
RIVER VALLEYS OF FAR SOUTHWESTERN WISCONSIN. OTHERWISE, THURSDAY  
WILL BE A FEW DEGREES WARMER WITH INCREASING CLOUD COVER OUT  
AHEAD OF THE NEXT WEATHER SYSTEM.  
 
THURSDAY AFTERNOON THROUGH FRIDAY: THUNDERSTORM POTENTIAL  
 
A SHORTWAVE TROUGH, ORIGINATING OUT OF THE CANADIAN PRAIRIE  
PROVINCES, IS FORECAST TO MOVE SOUTHEAST TOWARDS THE GREAT LAKES  
REGION THURSDAY INTO FRIDAY. OUT AHEAD OF THIS SYSTEM, MID LEVEL  
MOISTURE WILL INCREASE WHICH WILL RESULT IN THE FORMATION OF SHOWERS  
AND THUNDERSTORMS FROM THE NORTHERN PLAINS DOWN THROUGH THE UPPER  
MIDWEST. ALTHOUGH IT IS POSSIBLE A STORM MAY BE STRONG TO MARGINALLY  
SEVERE AS THEY MOVE INTO THE WESTERN CWA ON THURSDAY EVENING,  
CONFIDENCE IN THAT SCENARIO IS LOW SINCE CIN IS RAPIDLY INCREASING  
AS STORMS APPROACH THE AREA. FLOODING IS NOT REALLY A CONCERN WITH  
THE STORMS EITHER, AS PWAT VALUES ARE ONLY NEAR THE 75TH PERCENTILE  
(BASED ON SOUNDING CLIMATOLOGY FROM KMPX) AND THE STORMS SHOULD BE  
MOVING RELATIVELY QUICKLY. THE BULK OF THE PRECIPITATION SHOULD BE  
EAST OF THE AREA BY SUNRISE ON FRIDAY. CLOUD COVER SHOULD CLEAR OUT  
THROUGHOUT THE DAY AS DRIER AIR MAKES ITS WAY OVER THE AREA ONCE  
AGAIN AND TEMPERATURES SHOULD BE ABLE TO RISE UP INTO THE UPPER 70S  
TO LOWER 80S DURING THE AFTERNOON.  
 
THIS WEEKEND INTO NEXT WEEK: SEASONAL AND MOSTLY DRY CONDITIONS  
 
FORECAST GUIDANCE REMAINS CONSISTENT IN BUILDING A RIDGE OF HIGH  
PRESSURE ACROSS THE WESTERN AND CENTRAL US WITH A TROUGH ACROSS THE  
EASTERN US THIS WEEKEND INTO THE NEXT WORK WEEK. THIS PATTERN WOULD  
PLACE THE UPPER MISSISSIPPI RIVER VALLEY IN BETWEEN THESE SYSTEMS,  
WHICH DOES LEAD TO UNCERTAINTY REGARDING THE EXACT DETAILS OF THE  
FORECAST THROUGHOUT THIS TIME FRAME. IN GENERAL, THIS PATTERN FAVORS  
SEASONAL TEMPERATURES AND MOSTLY DRY CONDITIONS. ENSEMBLE FORECAST  
GUIDANCE HINTS AT THE POTENTIAL FOR SOME LIGHT RAINFALL EARLY NEXT  
WEEK, HOWEVER THAT WILL HIGHLY DEPEND UPON MOISTURE REMAINING OVER  
THE AREA AS WELL AS THE PRECISE TRACK OF UPPER LEVEL DISTURBANCES.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/  
 
ISSUED AT 1240 PM CDT WED AUG 19 2026  
 
VFR CONDITIONS ARE FORECAST WITH THIS TAF CYCLE. LIGHT AND  
VARIABLE WINDS ARE ALMOST CERTAIN THROUGH MUCH OF THIS 24 HOUR  
PERIOD. THE WIND WILL EVENTUALLY SHIFT TO OUT OF THE SOUTHWEST  
AT THE TERMINALS WITH THE WIND INCREASING UP TO 10 KTS AT THE  
END OF THIS TAF ISSUANCE. MOSTLY CLEAR SKIES ARE EXPECTED WITH  
SOME HIGH CLOUDS MOVING IN OVER THE REGION.  
 
 
   
ARX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
MN...NONE.  
IA...NONE.  
 
 
 
 
 
DISCUSSION...MUSCHA  
AVIATION...MUSCHA  
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