417  
FXUS63 KARX 232316  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
616 PM CDT SUN AUG 23 2026  
   
KEY MESSAGES
 
 
- PLEASANT TEMPERATURES ARE ON THE DOCKET FOR THE UPCOMING WEEK  
WITH HIGHS IN THE MID 70S TO MID 80S, WARMEST FOR MONDAY AND  
TUESDAY.  
 
- THE RISK FOR THUNDERSTORMS RETURNS FOR TUESDAY AFTERNOON AND  
EVENING, SOME OF WHICH MAY BE ON THE STRONGER SIDE.  
 
- SHOWERS MAY LINGER IN WISCONSIN INTO WEDNESDAY, WITH THE NEXT  
ROUND OF RAIN NOT EXPECTED UNTIL NEXT WEEKEND.  
 

 
   
DISCUSSION
 
 
ISSUED AT 1230 PM CDT SUN AUG 23 2026  
 
THIS AFTERNOON - MONDAY: PLEASANT AND DRY, COOL TONIGHT  
 
NORTHWESTERLY UPPER TROPOSPHERIC FLOW CONTINUES INTO MONDAY  
WITH SURFACE HIGH PRESSURE GRADUALLY SLIDING ACROSS THE REGION  
BETWEEN THIS AFTERNOON AND MONDAY AFTERNOON.  
 
TONIGHT'S MAIN FORECAST CONCERNS REVOLVES AROUND TEMPERATURES  
AND FOG ALONG AND EAST OF THE MISSISSIPPI RIVER, BOTH OF WHICH  
HINGE ON THE DEGREE OF CLOUD COVER THAT SPREADS SOUTHEASTWARD  
FROM NORTHERN HIGH PLAINS CONVECTION LATER THIS AFTERNOON. THE  
HIGH CIRRUS SHIELD IS NOT OVERLY THICK IN THE FORECAST  
SOUNDINGS, WHICH COULD RESULT IN A COMPLEX SCENARIO WHERE LOWER  
TEMPERATURES AND FOG SHIFT IN SPACE AND TIME DEPENDING ON THE  
CLOUD COVER. SHOULD THE CLOUDS WANE, LOWS TONIGHT COULD TOUCH  
THE UPPER 30S IN THE FAVORED SAND BOGS AND FOG COULD BE DENSE IN  
THE VALLEYS. THE ALTERNATE SCENARIO IS LOWS STAY MORE IN THE  
MID-40S WITH LITTLE FOG SHOULD THE CLOUDS COME IN THICKER.  
 
TUESDAY AFTERNOON: STORM POTENTIAL  
 
LITTLE CHANGE TO THE GOING FORECAST FOR THE RISK FOR STRONG TO  
EVEN SEVERE STORMS TUESDAY AFTERNOON AND EVENING AS A NOTABLE  
MID-TROPOSPHERIC VORT MAX/SHORTWAVE CRESTS OUR UPSTREAM RIDGE  
AND DIGS INTO MINNESOTA. FORECAST PROFILES CONTINUE TO SHOW A  
FAVORABLE WIND PROFILE FEATURING ELONGATED LOW TO MID-LEVEL  
HODOGRAPHS NORMAL TO THE SURFACE FRONT THAT WOULD SUPPORT  
ORGANIZED SUPERCELLULAR STRUCTURES. THE ISSUE IN THE MORE RECENT  
MEDIUM RANGE SOUNDINGS HAS BEEN AN EML AND DEEP SUB-CLOUD  
MIXING, WHICH RAPIDLY ERODE THE AVAILABLE INSTABILITY.  
 
WILL HAVE TO MONITOR CONDITIONS UPSTREAM CAREFULLY MONDAY  
NIGHT INTO TUESDAY MORNING TO SEE IF THE PREVIOUS DAY'S  
CONVECTION CAN MODULATE THIS LOWER TROPOSPHERIC AIRMASS TO  
SUPPORT MORE VIGOROUS UPDRAFTS. EVEN A SLIGHT COOLING AND  
MOISTENING TO THESE PROFILES COULD QUICKLY CHANGE HOW THESE  
STORMS EVOLVE, SO STAY TUNED FOR FURTHER UPDATES.  
 
END OF THE WEEK: DRIER ONCE AGAIN, POSSIBLY SOME WEEKEND RAIN  
 
A FEW SHOWERS MAY LINGER IN CENTRAL WISCONSIN ON WEDNESDAY WITHIN  
CYCLONIC FLOW FOLLOWING OUR LATE TUESDAY STORMS, BUT MOST OF  
THE AREA SHOULD STAY DRY FOR THE DAY. UPPER LEVEL RIDGING AND  
SURFACE HIGH PRESSURE RETURN FOR THE END OF THE WORK WEEK  
BRINGING SIMILAR CONDITIONS AS WE ARE SEEING TO START THE WEEK.  
THE PATTERN GROWS MORE ACTIVE HEADING INTO THE WEEKEND WITH THE  
POTENTIAL FOR MORE WIDESPREAD RAINFALL IN EXCESS OF 1 INCH.  
HOWEVER THE POSITION OF THE SYNOPTIC FEATURES ARE NOT WELL-  
RESOLVED AND MAKE IT DIFFICULT TO DELVE INTO AT THIS RANGE.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
 
 
ISSUED AT 616 PM CDT SUN AUG 23 2026  
 
MAIN AVIATION FORECAST CONCERN REVOLVES AROUND POTENTIAL FOG  
DEVELOPMENT IN VALLEYS AND LOW-LYING AREAS LATE TONIGHT, MAINLY  
EAST OF THE MISSISSIPPI RIVER. THE OVERALL SETUP IS FAVORABLE,  
BUT EXPECTED INCOMING HIGH CLOUDS WILL BE THE COMPLICATING  
FACTOR. RECENT RUNS OF THE NBM HAVE TRENDED TOWARD A BIT MORE  
CLOUD COVER AND THUS SLIGHTLY LOWER PROBABILITIES FOR MVFR FOG  
AT LSE. WILL MONITOR SATELLITE AND GUIDANCE TRENDS THIS EVENING  
FOR 06Z TAF.  
 
OTHERWISE VFR WITH LIGHT AND VARIABLE TO CALM WINDS OVERNIGHT,  
BECOMING SOUTH TO SOUTHWEST BY LATE MONDAY MORNING.  
 

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

 
 

 
 
DISCUSSION...SKOW  
AVIATION...KURZ  
 
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