802  
FXUS63 KARX 260537  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
1237 AM CDT SAT SEP 26 2026  
   
KEY MESSAGES  
 
- LIGHT RAIN CHANCES INCREASE FOR EARLY THIS MORNING AND THEN  
CONTINUE INTO THE AFTERNOON WITH THE HIGHEST CHANCES (40-100%)  
FOR AREAS WEST OF THE MISSISSIPPI RIVER. SMALL RAIN CHANCES  
(UP TO 20%) THEN CONTINUE FOR THE AREA INTO SUNDAY MORNING.  
 
- AFTER A DRY SUNDAY NIGHT INTO MONDAY NIGHT, RAIN CHANCES  
RETURN ON TUESDAY AND CONTINUE INTO WEDNESDAY.  
 
- NEAR-NORMAL TEMPERATURES PERSIST INTO NEXT WEEK WITH HIGHS IN  
THE 60S TO LOWER 70S.  
 
 
   
DISCUSSION  
 
ISSUED AT 1235 AM CDT SAT SEP 26 2026  
 
TODAY  
 
A SHORTWAVE TROUGH WILL EJECT NORTHEAST THROUGH THE UPPER  
MISSISSIPPI RIVER VALLEY. THE STRONGEST FORCING AND MOISTURE  
WILL BE LOCATED WEST OF THE MISSISSIPPI RIVER. WHILE THE CAMS  
ARE SHOWING THAT THE SHOWERS WILL DECREASE THEIR COVERAGE AS  
THEY MOVE EAST TOWARD THE MISSISSIPPI RIVER, THE SYNOPTIC  
FORCING AND 850 MB MOISTURE TRANSPORT LOOK TO BE STRONG ENOUGH  
TO PRODUCE AT LEAST SOME LIGHT RAINFALL TOTALS THROUGH THE  
MORNING AND INTO THE MID-AFTERNOON. DUE TO THIS, INCREASED THE  
RAIN CHANCES INTO THE 60-100% RANGE DURING THIS TIME FRAME.  
 
HIGH TEMPERATURES WILL BE IN THE 60S. DUE TO THE RAIN AND CLOUD  
COVER, THE COOLEST HIGH TEMPERATURES (LOWER 60S) WILL BE WEST  
OF THE MISSISSIPPI RIVER. MEANWHILE, WESTERN AND CENTRAL  
WISCONSIN WILL SEE HIGH TEMPERATURES IN THE MID- AND UPPER 60S.  
 
TONIGHT AND SUNDAY  
 
AS THE SHORTWAVE TROUGH CONTINUE TO MOVE NORTHEAST INTO A RIDGE  
OF HIGH PRESSURE OVER THE GREAT LAKES, THERE WILL BE  
FRONTOLYSIS ALONG THE SURFACE FRONT AND DRY SOUTHEAST WINDS WILL  
ADVECT DRIER AIR INTO THE REGION FOR TONIGHT AND SUNDAY  
MORNING. THIS SHOULD REDUCE THE SHOWER COVERAGE TO ISOLATED.  
 
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE MID-40S TO  
MID-50S. HIGH TEMPERATURES ON SUNDAY WILL BE IN THE MID-60S.  
 
SUNDAY NIGHT AND MONDAY NIGHT  
 
HIGH PRESSURE OVER THE GREAT LAKES WILL KEEP THE AREA DRY FROM  
SUNDAY NIGHT INTO MONDAY NIGHT.  
 
LOW TEMPERATURES ON SUNDAY NIGHT AND MONDAY NIGHT WILL RANGE  
FROM THE MID-40S TO MID-50S. THE COOLEST TEMPERATURES WILL BE IN  
CENTRAL AND NORTH-CENTRAL WISCONSIN. HIGH TEMPERATURES ON  
MONDAY WILL BE AROUND 70 DEGREES.  
 
TUESDAY INTO WEDNESDAY  
 
A NORTHERN STREAM SHORTWAVE TROUGH WILL MOVE THROUGH THE  
REGION. THIS SYSTEM LOOKS TO BE RATHER PROGRESSIVE, SO THIS MAY  
RESULT IN LESSER RAINFALL THAN PREVIOUSLY FORECAST. THERE IS A  
50-80% PROBABILITY OF A HALF-INCH OR GREATER AND A 30-65%  
PROBABILITY OF 1 INCH OR GREATER IN THE NBM.  
 
HIGH TEMPERATURES ON TUESDAY AND WEDNESDAY WILL RANGE FROM  
MID-60S TO AROUND 70. LOW TEMPERATURES ON TUESDAY NIGHT WILL BE  
IN THE 50S.  
 
THURSDAY INTO FRIDAY  
 
STILL PLENTY OF UNCERTAINTY ON HOW FAR NORTH THE REMNANTS OF  
POLO WILL GET. A FEW ENSEMBLE MEMBERS SUGGEST THAT THERE MIGHT  
BE A PRE (PREDECESSOR RAINFALL EVENT) SOUTH OF INTERSTATE 90. A  
THIRD OF MEMBERS SUGGEST THAT A WEAKENING SURFACE LOW AND ITS  
ASSOCIATED WARM FRONT MAY MOVE INTO THE REGION. MEANWHILE, THE  
OTHER MEMBERS KEEP THE AREA DRY. THE NBM CURRENTLY HAS THE  
PROBABILITIES OF AN INCH OF RAIN OR GREATER UP TO 40%.  
 
HIGH TEMPERATURES ON THURSDAY AND FRIDAY WILL BE IN THE  
MID-60S. LOW TEMPERATURES ON THURSDAY NIGHT WILL RANGE FROM THE  
MID-40S TO LOWER 50S.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/  
 
ISSUED AT 1235 AM CDT SAT SEP 26 2026  
 
PRIMARILY VFR CONDITIONS ARE EXPECTED AREAWIDE OVERNIGHT  
ALTHOUGH SIMILAR TO THE PAST FEW NIGHTS, PATCHY MIST/FOG MAY BE  
ABLE TO DEVELOP IN SOME OF THE VALLEYS AND LOW LYING AREAS  
(20-30%) THOUGH NEAR SURFACE DRY AIR AND UPPER LEVEL CLOUDS  
SHOULD KEEP IMPACTS MINIMAL.  
 
SHOWERS BEGIN TO MOVE INTO THE REGION FROM THE WEST TOWARDS  
DAYBREAK. CONFIDENCE IS HIGH THAT AREAS WEST OF THE MISSISSIPPI  
RIVER WILL SEE RAINFALL THROUGHOUT THE DAY (70-90%) THOUGH  
SHOWERS WILL BE LIGHT AND VISIBILITIES ARE EXPECTED TO REMAIN  
VFR. HOWEVER, MVFR CEILINGS ASSOCIATED WITH THE SHOWERS ALSO  
MOVE INTO THE REGION, IMPACTING THOSE SITES PRIMARILY WEST OF A  
KRST TO KCCY LINE. MUCH DRIER AIR ACROSS WISCONSIN SHOULD  
LARGELY INHIBIT RAINFALL EAST OF THE MISSISSIPPI RIVER (10-20%)  
WHERE VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF PERIOD.  
OTHERWISE, SOUTHEAST WINDS CONTINUE ACROSS THE REGION, GENERALLY  
AT 5-10KT WITH GUSTS OF 15-20KT WEST OF THE MISSISSIPPI RIVER  
THIS AFTERNOON.  
 
 
   
ARX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
MN...NONE.  
IA...NONE.  
 
 
 
 
 
DISCUSSION...BOYNE  
AVIATION...FALKINHAM  
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