965  
FXUS63 KARX 201204  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
704 AM CDT SUN SEP 20 2026  
   
KEY MESSAGES  
 
- A CLOUDY AND DAMP MORNING GIVES WAY TO PEAKS OF SUN THIS  
AFTERNOON.  
 
- A 20-40 PERCENT CHANCE OF SHOWERS MONDAY INTO MONDAY NIGHT,  
THROUGH IMPACTS LOOK TO BE MINIMAL.  
 
- COOLER AND DRIER CONDITIONS ARE EXPECTED THROUGH MUCH OF THE  
NEW WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 655 AM CDT SUN SEP 20 2026  
 
TODAY: LIGHT MORNING SHOWERS, DRYING OUT THIS AFTERNOON  
 
THE SURFACE BOUNDARY THAT WAS SITUATED ACROSS THE UPPER MISSISSIPPI  
RIVER VALLEY OVER THE PAST DAY OR SO HAS SHIFTED WELL SOUTH OF  
THE REGION, TAKING THE HEAVY RAINFALL SOUTH WITH IT. A FEW  
ELEVATED SHOWERS WILL PERCOLATE THROUGH THE MORNING, MAINLY  
SOUTH OF I-90, BEFORE DRIER AIR FILTERS IN FROM THE NORTH.  
CLOUDY SKIES LIKEWISE WILL START TO BREAK UP BY THIS AFTERNOON,  
BUT MOST LOCALES WILL SEE MORE CLOUDS THAN SUN TODAY. HIGHS  
TODAY SHOULD REMAIN SEASONABLY COOL WITH READINGS TOPPING OUT IN  
THE MID-60S TO AROUND 70, DICTATED BY THE EXACT DEGREE OF CLOUD  
COVER WE SEE.  
 
MONDAY: POTENTIAL FOR SHOWERS RETURNS  
 
MONDAY INTO MONDAY NIGHT BRINGS ADDITIONAL POTENTIAL FOR  
RAINFALL AS THE UPPER LEVEL CLOSED LOW CURRENTLY OVER THE  
NORTHERN ROCKIES SHIFTS EASTWARD INTO THE UPPER MIDWEST.  
CURRENTLY THINKING AREAS ALONG AND SOUTH OF I-90 WILL BE FAVORED  
TO SEE SHOWER ACTIVITY DURING THIS PERIOD AS THE CURRENT  
TRAJECTORY OF THE UPPER LOW AND THE PLACEMENT OF A SURFACE  
BOUNDARY SUGGESTS THE STRONGEST QG FORCING SHOULD RESIDE ACROSS  
THESE AREAS.  
 
RAINFALL AMOUNTS SHOULD BE ON THE LOWER SIDE COMPARED TO THE LAST  
DAY OR SO WITH THE 20.01Z NBM SUGGESTING AMOUNTS ARE FAVORED TO BE  
UNDER 1 INCH WITH ONLY A 10-20% CHANCE TO EXCEED THIS AMOUNT. THAT  
SAID, SOME FLOODING POTENTIAL DOES EXIST, MAINLY ACROSS SOUTHEAST  
MINNESOTA AND NORTHEAST IOWA, IF AMOUNTS EXCEED 1 INCH GIVEN THE  
SATURATED SOILS, BUT SHOULD LARGELY BE MITIGATED BY FAIRLY MARGINAL  
PARAMETERS FOR HEAVY RAINFALL.  
 
TUESDAY - FRIDAY: COOLER AND DRIER  
 
COOLER AND MORE FALL-LIKE TEMPERATURES ARE IN STORE FOR THE UPPER  
MISSISSIPPI RIVER VALLEY THROUGH MUCH OF THE NEW WEEK AS HIGH  
PRESSURE AND LOWER HEIGHTS BECOME SITUATED OVER THE GREAT LAKES BY  
TUESDAY WITH HIGHS IN THE 60S TO LOW 70S AND LOWS IN THE 40S. A  
DRIER AIRMASS ALSO SINKS SOUTHWARD INTO THE UPPER MIDWEST DURING  
THIS PERIOD, LIMITING ANY ADDITIONAL RAINFALL POTENTIAL AS WE HEAD  
INTO NEXT WEEKEND.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z MONDAY/  
 
ISSUED AT 539 AM CDT SUN SEP 20 2026  
 
MVFR AND LOWER CEILINGS ARE STILL BEING OBSERVED ACROSS THE AREA  
THIS MORNING. THE LOW CLOUDS SHOULD BEGIN TO LIFT AFTER SUNRISE  
AND A RETURN TO VFR CONDITIONS IS POSSIBLE AS EARLY AS 16-18Z.  
BRIEF MVFR CONDITIONS MAY CONTINUE THROUGH THE AFTERNOON, BUT  
THE CURRENT EXPECTATION IS THAT ONCE THE SITES BECOME VFR, THEY  
SHOULD REMAIN THAT WAY THROUGH THE REST OF THIS TAF ISSUANCE.  
THE WIND IS FORECAST TO STAY OUT OF THE EAST OVER THE NEXT 24  
HOURS WITH GUSTS UP TO 20-25 KTS DURING THE DAYTIME HOURS.  
 
 
   
HYDROLOGY  
 
ISSUED AT 655 AM CDT SUN SEP 20 2026  
 
MULTIPLE AREA RIVERS REMAIN ABOVE FLOOD STAGE. THE CEDAR RIVER  
AROUND AUSTIN IS CRESTING AND EXPECTED TO START FALLING TODAY.  
THE CREST IS WORKING DOWN THE ROOT RIVER IN FILLMORE AND HOUSTON  
COUNTIES WITH MOST LOCALES TOUCHING MINOR FLOOD STAGE TODAY OR  
TOMORROW BEFORE FALLING. ADDITIONAL CRESTS ARE WORKING DOWN THE  
TURKEY AND VOLGA RIVERS IN NORTHEAST IOWA WITH MINOR TO MODERATE  
FLOODING ONGOING OR EXPECTED OVER THE NEXT FEW DAYS. CONFIDENCE  
IN THE DEGREE OF FLOODING ALONG THE KICKAPOO IS ON THE LOWER  
SIDE GIVEN THAT THE RIVER HAS BEEN TRENDING LOWER THAN FORECAST  
WITH MOST LOCALES ONLY EXPECTED TO TOUCH FLOOD STAGE AT BEST.  
LITTLE ADDITIONAL IMPACTFUL RAINFALL IS EXPECTED TODAY.  
 
 
   
ARX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
MN...NONE.  
IA...NONE.  
 
 
 
 
 
DISCUSSION...FALKINHAM/SKOW  
AVIATION...MUSCHA  
HYDROLOGY...SKOW  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WI Page
The Nexlab IA Page
The Nexlab MN Page
Main Text Page