965  
FXUS63 KARX 191216  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
716 AM CDT WED AUG 19 2026  
   
KEY MESSAGES
 
 
- DRY AND PLEASANT TODAY.  
 
- NEXT ROUND OF STORMS ROLLS THROUGH THURSDAY AFTERNOON AND  
NIGHT WITH THE STORM THREAT LINGERING POTENTIALLY INTO  
FRIDAY. OVERALL IMPACTS LOOK TO BE MINIMAL.  
 
- SEASONAL TEMPERATURES REMAIN ON TAP THROUGH AT LEAST THE END  
OF THE WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 715 AM CDT WED AUG 19 2026  
 
DRY TODAY:  
 
A COOLER, DRIER AIRMASS WORKS THROUGH THE FORECAST AREA TODAY  
CONCURRENT WITH ANTICYCLONIC FLOW SOLIDIFYING DRIER CONDITIONS.  
 
STORM CHANCES THURSDAY:  
 
THE HIGH CONFIDENCE IN DRY CONDITIONS DECREASES THROUGH THURSDAY AS  
UPPER LEVEL EXTRATROPICAL CYCLONIC FLOW, SEEN ON GOES WATER VAPOR  
IMAGERY LOOPS TONIGHT OVER THE CANADIAN ROCKIES ENHANCES LOW LEVEL,  
MOISTURE-LADEN FLOW THROUGH THE UPPER MISSISSIPPI RIVER VALLEY.  
WHILE CURRENT TIMING AND STRENGTH OF ADVECTING FLOW AND FORCING  
ABATES HIGHER SEVERE STORM PROBABILITIES NORTHWEST OF THE LOCAL  
FORECAST AREA, A SLIGHT EASTERN SHIFT IN MACHINE LEARNING SEVERE  
HAZARD PROBABILITIES OVER RECENT RUNS NOW GRAZES THE WESTERN  
PERIPHERY OF THE LOCAL FORECAST AREA WITH 5-15%. THEREFORE, WHILE  
CURRENT CONFIDENCE IS LOWER (<15%), FARTHER EASTERN SHIFT IN MODEL  
SOLUTIONS WILL BE THE INITIAL LOCALLY IMPACTFUL DETAIL TO REMAIN  
COGNIZANT OF IN COMING FORECASTS.  
 
HEAVY RAIN CHANCES FRIDAY:  
 
WHILE /MOST/ LONG TERM GLOBAL ENSEMBLE MODELS AND THEIR  
DETERMINISTIC COUNTERPARTS AGREE ON THE ACCOMPANYING LOW CENTER  
REMAINING RELATIVELY BENIGN INITIALLY THROUGH THURSDAY, GLANCING  
LOCALLY NORTHERN COUNTIES IN WEST-CENTRAL AND CENTRAL WISCONSIN WITH  
HIGHEST (100%) PRECIPITATION PROBABILITIES, DEEPENING OF THE  
ACCOMPANYING LINGERING TROUGH HAS INCREASED PROBABILITIES FOR  
HEAVIER (0.1" & 0.5" /24HRS) RAINFALL ACROSS THE NORTHERN /HALF/ OF  
THE FORECAST AREA THROUGH FRIDAY AND INTO THE WEEKEND IN MOST RECENT  
ENSEMBLE RUNS. SHOULD THURSDAY NIGHTS STORM ADVECTION RESULT IN MORE  
EASTERN SOLUTION TO THE ACCOMPANYING FRONTAL BOUNDARY, THIS THREAT  
WOULD SHIFT EAST, POTENTIALLY EAST OF THE LOCAL FORECAST AREA.  
THEREFORE, ALTHOUGH CURRENT WPC EXCESSIVE RAINFALL OUTLOOKS DON'T  
DEPICT MUCH OF A THREAT, WILL BE SUBSEQUENT DETAIL TO MONITOR IN  
COMING FORECASTS. SEVERE STORM THREAT REMAINS CONDITIONAL ON  
CLEARING SKIES PERMITTING LOW LEVEL DIURNAL INSTABILITY TO BUILD AS  
LONG, SKINNY INSTABILITY PROFILES IN INDIVIDUAL LREF MEMBER PLUMES  
EXHIBIT STUNTED HODOGRAPHS UNTIL THE STRONGER MID-UPPER LEVEL WINDS  
FRIDAY NIGHT INTO SATURDAY.  
 
MOSTLY COOL & DRY WEEKEND:  
 
IN THE WAKE OF FRIDAY'S STORM POTENTIAL, A COOLER WEEKEND IS  
EXPECTED WITH DAYTIME HIGHS FROM THE 70S TO LOW 80S THROUGH MONDAY.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
 
 
ISSUED AT 535 AM CDT WED AUG 19 2026  
 
VFR CONDITIONS ARE EXPECTED THROUGHOUT MUCH OF THE TAF PERIOD ASIDE  
FROM THE POTENTIAL FOR INITIAL VALLEY FOG/LOW-STRATUS AT KLSE THIS  
MORNING. CURRENTLY, MANY RIVER VALLEY LOCATIONS IN SOUTHWEST WI ARE  
NOTING VSBYS OF 1/2SM TO 1/4SM, HOWEVER MID-LEVEL CLOUDS AIDED IN  
IMPROVING VSBYS AT KLSE. IT IS UNCLEAR IF REDEVELOPMENT WILL  
OCCUR AT KLSE, HOWEVER SATELLITE TRENDS DO NOT APPEAR OVERLY  
FAVORABLE AS OF 1030Z. IN ANY CASE, FOG THAT DOES DEVELOP WILL  
DISSIPATE BY MID-MORNING LEAVING VFR CONDITIONS WITH WINDS  
GENERALLY BEING LIGHT AND VARIABLE THROUGHOUT THE TAF PERIOD.  
 

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

 
 

 
 
DISCUSSION...JAR/SKOW  
AVIATION...NAYLOR  
 
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