673  
FXUS63 KARX 092338  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
638 PM CDT TUE SEP 9 2025  
   
KEY MESSAGES
 
 
- SCATTERED SHOWER/STORMS THIS AFTERNOON/TONIGHT - MOSTLY ACROSS  
PARTS OF SOUTHEAST MN/WESTERN WI  
 
- WARMING THROUGH THE WEEKEND, TOPPING 80 DEGREES FOR HIGHS FOR MANY  
FRI-SUN.  
 

 
   
DISCUSSION
 
 
ISSUED AT 135 PM CDT TUE SEP 9 2025  
 
REST OF TODAY/TONIGHT: CONVECTION FIRING ACROSS SOUTHERN MN/NORTHERN  
IA IN RESPONSE TO AN UPPER LEVEL SHORTWAVE TROUGH WILL CONTINUE TO  
SHIFT EAST ACROSS THE FORECAST AREA FOR THE REST OF THE  
AFTERNOON/TONIGHT. LOW LEVEL JET PICKS UP A BIT BY 00Z, AIDING THE  
LIFT. PWS AS MUCH AS 1 1/2" BUT WARM CLOUD DEPTHS GENERALLY UNDER 3  
KFT - LIMITING ANY HEAVIER RAIN RISK TO VERY LOCALIZED.  
SHOWER/STORMS ALSO SHIFTING AWAY FROM THE MAIN INSTABILITY POOL -  
WORKING AGAINST STRONGER STORMS. TRACK OF THE SHORTWAVE POSITIONS  
MORE OF THE AREAL COVERAGE OVER SE MN/WESTERN WI - DEPICTED BY THE  
MAJORITY OF THE CAMS. WILL FOLLOW SUIT.  
 
A DECREASE OVERNIGHT IN AREAL COVERAGE/INTENSITY, BUT WITH THE SLOW  
MOVEMENT EAST OF THE TROUGH, AT LEAST SOME LOW END RAIN CHANCES  
(20%) WILL LINGER OVER WESTERN WI WED MORNING.  
 
THROUGH THE WEEKEND/EARLY NEXT WEEK:  
 
> OVERVIEW: UPPER LEVEL RIDGE BUILDS ACROSS THE REGION FOR THE  
WEEKEND WHILE WEST COAST TROUGH LIFTS NORTHEAST ACROSS THE  
ROCKIES/NORTHERN PLAINS. NEITHER FEATURE IS PARTICULARLY "STOUT"  
WITH LONG TERM GUIDANCE FAVORING A BREAK DOWN OF THE TROUGH WITH  
SOME WEAKENING IN THE RIDGE. WARMER AIR WILL POOL UNDER THE RIDGE,  
MAKING FOR A RELATIVELY "WARM" FOR THE SEASON SECOND HALF TO THIS  
WEEK, BUT BITS OF UPPER LEVEL ENERGY WILL SPIN OUT OF THE TROUGH,  
WORKING ACROSS THE RIDGE TOO. THIS WILL BRING A SMATTERING OF RAIN  
CHANCES.  
 
SOME SUGGESTIONS IN THE LONG RANGE GUIDANCE FOR MORE ZONAL FLOW FOR  
NEXT WEEK, BUT STILL WEAK WITHOUT ANY SIGNFICIANT TROUGHING/RIDGING  
ON THE HORIZON. WPC CLUSTERS SHOW SIMILAR DISINTEREST IN SKETCHING  
OUT SOMETHING MORE DEFINED. TEMPS WOULD MODERATE TO THE SEASONABLE  
NORMS IN THIS SCENARIO WITH A CONTINUED SMATTERING OF RAIN CHANCES  
HERE AND THERE. ENSEMBLE GUIDANCE VARIABILITY AND RELATIVELY WEAK  
SIGNALS KEEP PREDICTABILITY AND CONFIDENCE LOW IN THE DETAILS.  
 
> TEMPS: WARMER AIR SET TO PUSH NORTHWARD UNDER THE ENCROACHING  
RIDGE AS WE MOVE INTO THE WEEKEND. LONG RANGE GUIDANCE/ENSEMBLE  
SUITES START PUSHING 80+ DEGREE AS SOON AS THU, BUT MORE LIKELY  
FRIDAY THROUGH THE WEEKEND. SAT CURRENTLY SHAPING UP TO BE THE  
WARMEST OF THE BUNCH WITH THE GRAND ENSEMBLE PAINTING 60-80% CHANCES  
FOR 80+ DEGREE HIGHS ALONG/SOUTH OF I-94 SAT, A BIT LESS SUNDAY. IF  
THE GEFS HAS ITS WAY, UPPER 80S TO AROUND 90 WOULD BE REACHED FOR A  
FEW LOCATIONS WITH 50% OF ITS MEMBERS FAVORING THE HOTTER SUMMER  
WARMTH. THINK THE GEFS IS SUFFERING FROM A MODEL BIAS AND TOO WARM  
FOR THIS PERIOD - ALTHOUGH A SMALL SUBSET OF THE EPS (10%) HINT THAT  
IT COULD HAPPEN. FOR NOW, WILL STICK WITH THE MODEL BLEND. NORTH OF  
THERE A TAD COOLER BUT UPPER 70S/LOWER 80S STILL TRACKING.  
 
ALTHOUGH HOW THE UPPER LEVEL FLOW SETS UP FOR NEXT WEEK IS NOT  
CLEAR, THE GENERALLY TRENDS WOULD FAVOR TEMPS COOLING BACK TOWARD  
THE MID SEP NORMS.  
 
> RAIN CHANCES: AS MENTIONED, MOSTLY WEAK SIGNALS VIA THE LONG RANGE  
ENSEMBLES BUT ALL SUGGESTIVE OF PERSISTENT BITS OF UPPER LEVEL  
ENERGY SPINNING NEAR/ACROSS THE UPPER MISSISSIPPI RIVER VALLEY.  
RESULTING RAIN CHANCES, AREAL COVERAGE AND TIMING SUFFER FROM THE  
WEAK SIGNALS AND ENSEMBLE DIFFERENCES. WILL HOLD WITH THE MODEL  
BLEND WHICH PAINTS A SMATTERING OF LOW END CHANCE HERE AND THERE.  
EXPECT SOME REFINEMENT IN THESE RAIN CHANCES AS WE MOVE THROUGH THE  
WEEKEND.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z THURSDAY/
 
 
ISSUED AT 638 PM CDT TUE SEP 9 2025  
 
VFR CONDITIONS EXPECTED UNTIL ~06Z AS LOW LEVEL CIGS AND FOG  
MOVE INTO PORTIONS OF SOUTHEAST MINNESOTA AND WESTERN WISCONSIN  
(NORTH OF I-90) CAUSING LOWERED FLIGHT CATEGORIES TO OCCUR.  
THIS FOG WILL BE DENSE AT TIMES IN THESE AREAS. THE FOG AND LOW  
LEVEL CLOUDS ARE EXPECTED TO LIFT BY MID-MORNING WEDNESDAY.  
OUTSIDE OF THESE AREAS, MID LEVEL CLOUDS MOSTLY AROUND 5KFT WILL  
BE OCCURRING THROUGHOUT THE TAF PERIOD. WHILE THE FOG AND LOW  
LEVEL CLOUDS ARE EXPECTED TO GET SOUTH OF I-90, THERE IS A 20 TO  
40% CHANCE THAT MVFR CIGS MOVE SOUTH OF I-90 AND GET INTO  
PORTIONS OF NORTHEAST IOWA AND SOUTHWESTERN WISCONSIN. SCATTERED  
SHOWERS AND A LOW CHANCE OF THUNDER (10%) WILL BE POSSIBLE  
THROUGH THE OVERNIGHT OVER MUCH OF THE AREA. LIGHT AND VARIABLE  
WINDS OVERNIGHT SHIFT TO LIGHT NORTHERLY WINDS BY WEDNESDAY  
AFTERNOON.  
 

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

 
 

 
 
DISCUSSION...RIECK  
AVIATION...CECAVA  
 
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