609  
FXUS63 KGRB 260610  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
110 AM CDT TUE MAY 26 2026  
 
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE  
   
KEY MESSAGES  
 
- HOT RECORD TO NEAR-RECORD TEMPERATURES EXPECTED THIS AFTERNOON,  
WITH HIGHS IN THE UPPER 80S TO LOWER 90S.  
 
- 50 TO 70% CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON  
AND THIS EVENING ACROSS CENTRAL AND EAST-CENTRAL WISCONSIN, WITH  
SOME STRONG TO MARGINALLY SEVERE STORMS POSSIBLE WITH LARGE  
HAIL AND STRONG WINDS.  
 
- ISOLATED THUNDERSTORMS ARE POSSIBLE WEDNESDAY AFTERNOON ACROSS  
CENTRAL WISCONSIN. A FEW STORMS COULD BECOME STRONG TO SEVERE  
WITH LARGE HAIL AND DAMAGING WINDS.  
 
- ABOVE NORMAL TEMPERATURES ARE EXPECTED THROUGH EARLY NEXT WEEK,  
WITH HIGHS FORECAST MAINLY IN THE UPPER 70S AND 80S.  
 
 
   
DISCUSSION  
 
ISSUED AT 110 AM CDT TUE MAY 26 2026  
 
A COLD FRONT, CURRENTLY SITUATED ACROSS THE NORTHERN GREAT LAKES,  
WILL SLOWLY SINK SOUTH INTO NORTHERN WISCONSIN THIS AFTERNOON,  
CENTRAL WISCONSIN TONIGHT, THEN THROUGH SOUTHERN WISCONSIN ON  
WEDNESDAY.  
 
AHEAD OF THE COLD FRONT A VERY WARM AIRMASS WILL BE IN PLACE AS  
HIGH TEMPERATURES TODAY SOAR INTO THE UPPER 80S TO THE LOWER 90S,  
WITH THE HIGHEST TEMPERATURES JUST WEST OF THE FOX VALLEY. THESE  
HOT TEMPERATURES WILL REACH RECORD TO NEAR-RECORD VALUES AS MANY  
LOCATIONS RECORDS ARE AROUND 90 DEGREES. DESPITE THE HOT  
TEMPERATURES EXPECTED, DEW POINTS WILL ONLY BE AROUND 60 DEGREES  
WHICH WILL KEEP HEAT INDEX VALUES MANAGEABLE.  
 
THE WARM TEMPERATURES WILL ALLOW INSTABILITY TO BUILD ACROSS THE  
REGION THIS AFTERNOON, AS SBCAPES RISE TO 1500 TO 3000 J/KG.  
DESPITE THE ABUNDANT INSTABILITY, EFFECTIVE SHEAR IS ONLY EXPECTED  
TO BE 10 TO 20 KNOTS WITH A FAIRLY WEAK WIND FIELD ALOFT. FORCING  
IS NOT ALL THAT IMPRESSIVE IN THE MIDDLE AND UPPER LEVELS, WITH  
THE MAIN LIFTING MECHANISM EXPECTED TO BE THE FAIRLY SHALLOW BACK  
DOOR COLD FRONT EXPECTED TO SLOWLY SINK SOUTH THROUGH THE EVENING.  
THAT BEING SAID, MODEL SOUNDINGS DO SHOW AN INVERTED-V IN THE  
LOWEST LEVELS OF THE ATMOSPHERE WITH DCAPE VALUES AROUND 1000  
J/KG, WHICH IS CONDUCIVE FOR DOWNBURSTS, AS WELL AS DECENT CAPE  
PROFILES IN THE HAIL GROWTH ZONE. THIS POINTS TO MARGINAL PULSE  
SEVERE STORMS LATER THIS AFTERNOON INTO EARLY THIS EVENING WHEN  
INSTABILITY IS MAXIMIZED ACROSS THE REGION.  
 
PRECIPITATION CHANCES WILL FALL OFF PRECIPITOUSLY AS THE EVENING  
WEARS ON AS THE FRONT SINKS SOUTH AND INSTABILITY WANES. DRY  
WEATHER IS THEN EXPECTED THROUGH WEDNESDAY MORNING WITH ADDITIONAL  
CHANCES FOR SHOWERS AND THUNDERSTORMS (20-30% CHANCE) WEDNESDAY  
AFTERNOON ACROSS CENTRAL WISCONSIN AS A WEAK SHORTWAVE TRACKS  
THROUGH THE WESTERN GREAT LAKES. THERE WILL BE A RESERVOIR OF  
1000-2000 J/KG OF SBCAPE AS THIS SHORTWAVE TRACKS THROUGH CENTRAL  
WISCONSIN WITH A BIT BETTER BULK SHEAR VALUES AROUND 30 KNOTS.  
ALTHOUGH STORMS WILL BE MORE ISOLATED IN COVERAGE, ANY STORMS THAT  
DEVELOP COULD BE MARGINALLY SEVERE STORMS GIVEN THE BETTER SHEAR  
AND STILL DECENT INSTABILITY.  
 
HIGH PRESSURE THEN SETTLES IN ACROSS THE REGION LATER THIS WEEK,  
WHICH IS EXPECTED TO KEEP THE REGION DRY THROUGH THE UPCOMING  
WEEKEND AND EVEN THROUGH THE EARLY PART OF NEXT WEEK.  
 
AFTER THE HOT TEMPERATURES EXPECTED TODAY, TEMPERATURES WILL FALL  
A BIT BUT STILL REMAIN ABOVE NORMAL FOR THE REST OF THE WEEK AND  
INTO THE EARLY PART OF NEXT WEEK.  
 
 
   
AVIATION  
FOR 06Z TAF ISSUANCE  
ISSUED AT 1047 PM CDT MON MAY 25 2026  
 
QUIET CONDITIONS ARE EXPECTED THROUGH TUESDAY MORNING, WITH ONLY A  
SMALL CHANCE OF SHOWERS NEAR THE UPPER MICHIGAN BORDER OVERNIGHT,  
AND LLWS OVERNIGHT INTO EARLY TUESDAY. A COLD FRONT WILL SAG  
SOUTH ACROSS THE FORECAST AREA ON TUESDAY, WITH SHOWERS AND SCATTERED  
THUNDERSTORMS DEVELOPING DURING THE MID TO LATE AFTERNOON, AND  
CONTINUING ACROSS C/EC WI THROUGH THE EVENING. HAVE ADDED TEMPO  
GROUPS FOR THE MOST LIKELY 4-HOUR PERIOD FOR THUNDERSTORMS.  
 
SOUTH TO SOUTHWEST WINDS WILL GUST TO AROUND 15 KTS AT TIMES  
THROUGH MOST OF THE TAF PERIOD, BUT WILL TURN NE IN THE WAKE OF  
THE FRONTAL PASSAGE TUESDAY AFTERNOON/EVENING.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
BEACH HAZARDS STATEMENT UNTIL 7 AM CDT THIS MORNING FOR WIZ022-  
040-050.  
 
 
 
 
DISCUSSION.....KURIMSKI  
AVIATION.......KIECKBUSCH  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WI Page
Main Text Page