686  
FXUS63 KARX 262337  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
637 PM CDT FRI JUL 26 2024  
   
KEY MESSAGES
 
 
- SUMMER HEAT/HUMIDITY RETURN THIS WEEKEND, HANGING AROUND FOR MUCH  
OF THE NEW WEEK. HIGHS FROM THE MID 80S TO AROUND 90 WITH HEAT  
INDICES ABOUT 5 DEGREES WARMER EXPECTED.  
 
- SHOWER/STORM CHANCES RETURN FOR SUN/MON. LOCALLY HEAVY RAIN  
POSSIBLE.  
 

 
   
DISCUSSION
 
 
ISSUED AT 120 PM CDT FRI JUL 26 2024  
 
OVERVIEW: UPPER LEVEL RIDGE SITS OVERHEAD TODAY AND IS STILL ON PACE  
TO SLIDE EAST OVER THE WEEKEND. THE UPPER LEVEL FLOW THEN SHIFTS TO  
BROAD RIDGING FOR THE NEW WEEK, A CONSISTENT SIGNAL IN BOTH THE GEFS  
AND EPS. WARMER, MORE MOIST AIR POOLS NORTHWARD UNDER THE RIDGE AND  
A RETURN TO "SUMMERY" AIR SHOULD BE PLANNED FOR THIS WEEKEND,  
THROUGH MOST/IF NOT ALL OF THE NEW WEEK. THE PATTERN SHIFT WILL ALSO  
ALLOW FOR SHORTWAVE TROUGHS TO HAVE A BETTER OPPORTUNITY TO SPIN  
NEAR/THROUGH THE AREA - AND RAIN CHANCES RETURN TO THE FORECAST AS A  
RESULT.  
 
HOW LONG THE BROAD RIDGING HOLDS IS A QUESTION. SOME MIXED MESSAGES  
BETWEEN THE GEFS AND EPS SUITE OF MEMBERS, WHICH SHOWS IN THE LATEST  
RUN OF THE WPC CLUSTER ANALYSIS. THE BULK OF THE EPS MEMBERS HOLD  
ONTO THE BROAD RIDGING THROUGH THE WEEKEND WHILE MORE OF THE GEFS  
SUITE SUGGEST REAMPLIFICATION OF THE WEST COAST RIDGE. SENSIBLE  
WEATHER OUTCOMES WOULD BE A CONTINUATION OF THE WARMTH IN THE EPS  
BUT COOLER/LESS HUMID VIA THE GEFS. A FAIR AMOUNT OF VOLATILITY IN  
THE MODELS THAT FAR OUT AT THIS TIME, KEEPING CONFIDENCE LOW IN  
WHICH WAY TO TREND. THAT SAID, THERE DOES SEEM TO BE MORE SUPPORT TO  
HOLD THE BROAD RIDGING PATTERN TROUGH THE WEEKEND. WE'LL SEE...  
 
TEMPS: SAY "HELLO" TO SUMMER, SHE'S BACK. WARMER, MORE MOIST AIR  
WILL START TO POOL NORTHWARD THIS WEEKEND AND SETTLE IN FOR THE NEW  
WEEK. THE EPS SUITE CONTINUES TO BE THE WARMEST OF THE LONG TERM  
GUIDANCE WITH 75% OF ITS MEMBERS PUSHING HIGH TEMPS INTO THE UPPER  
80S/LOWER 90S. GEFS IS A FEW/SEVERAL DEGREES COOLER - BUT STILL AT  
OR ABOVE THE LATE JULY/EARLY AUGUST NORMALS. WITH DEWPOINTS EXPECTED  
TO CLIMB INTO THE UPPER 60S TO LOWER 70S, TACK ON AT LEAST ANOTHER 5  
DEGREES FOR WHAT IT WILL "FEEL LIKE" (HEAT INDEX). NOT CURRENTLY  
TRENDING HOT ENOUGH WHERE HEADLINES WOULD BE NEEDED (HEAT  
ADVISORIES), BUT CERTAINLY AMPLE ENOUGH HEAT THAT THOSE WITH OUTDOOR  
PLANS SHOULD PREPARE FOR IT. MORE UNCERTAINTY MOVING INTO NEXT  
WEEKEND WITH THE DIFFERENCES IN THE MODELS SENDING MIXED MESSAGES.  
 
RAIN CHANCES: MED/LONG RANGE GUIDANCE CONTINUES TO SPIN BITS OF  
SHORTWAVE ENERGY NORTHEAST ACROSS THE REGION FOR SUN/MON AS THE  
RIDGE EXITS EAST. KIND OF A HODGEPODGE OF PIECES OF ENERGY WHICH MAY  
OR MAY NOT COALESCE INTO ONE MORE COHESIVE (AND STRONGER) SHORTWAVE.  
STILL, MIX OF FORCING AND FAVORABLE AIRMASS LOOK TO TRIGGER AREAS OF  
SHOWERS/STORMS SUN THROUGH MON. PWS UPWARDS 2" AND WARM CLOUD DEPTHS  
NEAR 4 KFT SUGGEST A LOCALLY HEAVY RAIN POTENTIAL. STRONG/SEVERE  
RISK IS MORE NEBULOUS WITH TIMING OF THE SYSTEM(S) PLAYING A LARGER  
ROLE. THERE WILL BE INSTABILITY TO WORK WITH BUT DEEP LAYER SHEAR  
MAY HOLD FARTHER WEST.  
 
AFTER MONDAY, THE MODELS SHOW A VARIETY OF POTENTIAL RAIN MAKERS  
FOR THE REGION, WITH DIFFERENCES IN TIMING/PLACMENT/STRENGTH. WHICH  
DAY(S) HARBOR THE HIGHER CHANCES AREN'T CLEAR AND WILL ROLL WITH THE  
MODEL BLEND FOR NOW.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
 
 
ISSUED AT 637 PM CDT FRI JUL 26 2024  
 
VFR CONDITIONS EXPECTED. SOUTH AND SOUTHEAST WINDS OVERNIGHT  
BEFORE SHIFTING TO SOUTHWEST WINDS BY SATURDAY AFTERNOON.  
CURRENT CONDITIONS HAVE SOME LOWER LEVEL CLOUDS, BETWEEN 2500FT  
AND 5000FT, ACROSS PORTIONS OF SOUTHEAST MINNESOTA AND NORTHEAST  
IOWA. THESE CLOUDS WILL GRADUALLY SHIFT EASTWARD DURING THE  
OVERNIGHT PERIOD. AS A RESULT OF THESE CLOUD LEVELS, THERE WILL  
BE TIMES THAT AREAS MAY GO DOWN INTO THE MVFR FLIGHT CATEGORY.  
 

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

 
 

 
 
DISCUSSION...RIECK  
AVIATION...CECAVA  
 
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