440  
FXUS63 KMKX 251953  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
253 PM CDT FRI JUL 25 2025  
   
KEY MESSAGES
 
 
- ISOLATED TO SCATTERED THUNDERSTORMS (20-30%) THIS EVENING  
ALONG THE WI/IL BORDER. BETTER CHANCES (30-60%) LATE TONIGHT  
AND SATURDAY, ESPECIALLY FOR AREAS SOUTH OF HWY-151.  
 
- HOT AND VERY HUMID SUNDAY AND MONDAY WITH UPPER 90S TO TRIPLE  
DIGITS HEAT INDICES.  
 
- PERIODIC SHOWER/STORM CHANCES THROUGH LATER SUNDAY AND INTO  
EARLY NEXT WEEK BEFORE AN EVENTUAL COLD FRONT PASSAGE MIDWEEK.  
 

 
   
SHORT TERM
 
 
ISSUED 253 PM CDT FRI JUL 25 2025  
 
TONIGHT THROUGH SATURDAY NIGHT:  
 
HIGH PRESSURE REMAINS CENTERED OVER THE UPPER GREAT LAKES WITH  
THE STALLED FRONTAL BOUNDARY SET UP SOUTH ACROSS IL/IN. THIS  
AFTERNOON IS STILL FAIRLY WARM WITH NOT MUCH RELIEF IN DEWPOINTS  
(UPPER 60S- LOW 70S) EVEN WITH EASTERLY WINDS OFF OF THE LAKE.  
THE HIGH WILL GRADUALLY SLIDE EAST THIS EVENING/TONIGHT WITH  
OVERNIGHT LOWS IN THE MID TO UPPER 60S BEFORE SOUTHERLY FLOW  
GRADUALLY BUILDS BACK INTO SOUTHERN WI AND WILL SEE THE STALLED  
BOUNDARY LIFT BACK NORTHWARD AS WELL. COULD SEE A FEW SHOWERS  
AND STORMS LATER THIS EVENING AS THE ELEVATED HUMIDITY LEVEL  
PAIRED WITH A LIFTING WARM FRONTAL BOUNDARY AND MCV (CURRENTLY  
CENTERED ACROSS SOUTHERN IA) MAY TRIGGER DEVELOPMENT ACROSS FAR  
SOUTHERN WI. HOWEVER MODEL TRENDS ARE LEANING MORE IN FAVOR OF  
THE LATE EVENING ACTIVITY EITHER HUGGING THE WI/IL BORDER OR  
STAYING SOUTH WHERE THE FRONT LINGERS A BIT LONGER WITH THE  
SUB-30 KT LLJ.  
 
EXPECTING MORE WIDESPREAD SHOWER AND STORM ACTIVITY TO DEVELOP  
INTO SATURDAY MORNING AS ANOTHER MCS/MCV, CURRENTLY CENTERED  
OVER NE/KS BORDER, LIFTS NORTHEASTWARD INTO THE REGION. WITH THE  
RETURN OF HIGHER MOISTURE AND PWATS CREEPING BACK ABOVE 1.5 TO  
AROUND 2 INCHES, EXPECTING INCREASED SHOWER CHANCES THROUGH  
SATURDAY MORNING AS A MID-LEVEL SHORTWAVE TROUGH LIFTS IN FROM  
THE SOUTHWEST ACROSS WI/IL. LATEST MODEL TRENDS CONTINUE TO  
FAVOR THE SOUTHERN HALF OF THE CWA (ALONG AND SOUTH OF I-94) TO  
SEE MUCH OF THIS ACTIVITY, BUT COULD SEE IT AS FAR NORTH AS  
HWY-151, WITH AREAS NORTHWEST REMAINING MOSTLY DRY. HOWEVER  
GIVEN THE UNCERTAIN NATURE OF AN MCS, COULD SEE THINGS SHIFT  
DEPENDING ON WHERE THE FEATURES ENDS UP TRACKING. GIVEN THE  
INCREASING MOISTURE, WILL SEE INSTABILITY CLIMB WITH THE 12Z  
HREF PROGGING AT LEAST 500-1000J/KG OF MUCAPE ACCOMPANYING THE  
INCOMING MCS. THUS FEW EMBEDDED THUNDERSTORMS WILL BE POSSIBLE  
SATURDAY MORNING INTO THE EARLY AFTERNOON. ANY DELAY IN THE  
TIMING OF THE MCS AND MORNING SHOWER ACTIVITY WILL HELP  
INSTABILITY CLIMB UPWARD AND INCREASE THE THUNDERSTORM  
POTENTIAL INTO THE AFTERNOON. IF THIS SCENARIO ENDS UP PANNING  
OUT, THEN CANNOT RULE OUT SEEING A STORM OR TWO GROW TALL ENOUGH  
AND PRODUCE GUSTY WINDS AND EVEN SOME SMALL HAIL. HOWEVER,  
CONTINUE TO SEE THE BETTER POTENTIAL FOR STRONGER STORM FURTHER  
SOUTH INTO IL WHERE THE GREATER INSTABILITY AND DEEP LAYER SHEAR  
WILL BE IN ASSOCIATED AHEAD OF THE MCS.  
 
MUCH OF THE SHOWER AND STORM ACTIVITY DOES LOOK TO BE THROUGH  
THE AREA BY THE LATER HALF OF THE AFTERNOON. WHILE LOOKING AT A  
DRIER EVENING, NOT EXPECTING MUCH OF A CHANGE IN AIRMASS SO THE  
HUMIDITY WILL LINGER INTO SATURDAY NIGHT WITH LOWS IN THE UPPER  
60S TO LOW 70S.  
 
WAGNER  
 

 
   
LONG TERM
 
 
ISSUED 253 PM CDT FRI JUL 25 2025  
 
SUNDAY THROUGH FRIDAY:  
 
UPPER-LEVEL HIGH PRESSURE REMAINS ESTABLISHED OVER SOUTHEASTERN  
CONUS INTO EARLY NEXT WEEK. THIS WILL PLACE SOUTHERN WI AT THE  
TOP OF THE UPPER RIDGE WITH SOUTHWESTERLY FLOW ADVECTING IN A  
MORE TROPIC AIRMASS INTO SOUTHERN WI SUNDAY THROUGH THE START OF  
NEXT WEEK. GIVEN THIS PATTERN, IT LENDS WAY TO ANOTHER HOT AND  
HUMID STRETCH WITH TEMPS IN THE UPPER 80S INTO THE 90S AND EVEN  
HOTTER HEAT INDICES RANGING FROM THE MID-90S INTO TRIPLE DIGITS,  
ESPECIALLY FOR MONDAY AND MAY EVEN SEE THE HEAT CONTINUE INTO  
TUESDAY. THUS HEAT HEADLINES MAY BE NEEDED EARLY NEXT WEEK.  
HOWEVER, THERE CONTINUES TO BE UNCERTAINTY WITH TEMPS AS PERIODS  
OF SHOWERS/STORMS FROM UPPER-LEVEL WAVES OVERRUNNING THE RIDGE  
AND BRINGING AN MCS OR TWO ACROSS THE REGION MAY PRESENT A  
WRINKLE IN THE FORECAST LIMITING THE HEAT POTENTIAL. DIFFICULT  
TO PINPOINT THE CLOUD COVER AND SHOWER/STORM CHANCES FROM A WAVE  
OR TWO THIS FAR OUT, BUT MID-RANGE MODELS HINT A FEW  
OPPORTUNITIES ONE BEING SUNDAY NIGHT INTO MONDAY AND AGAIN ON  
MONDAY NIGHT INTO TUESDAY. NEVERTHELESS WILL BE THE POTENTIAL  
FOR WAVE OF SHOWERS/STORMS TO ACCOMPANY THE HOT AND HUMID  
STRETCH INTO EARLY NEXT WEEK.  
 
UPPER-LEVEL HIGH GRADUALLY MEANDERS BACK WESTWARD MIDWEEK AND  
WILL ALLOW FOR THE UPPER-LEVEL TROUGH TO WORK ITS WAY ACROSS THE  
UPPER MIDWEST. WITH THE RIDGE TO THE WEST, NORTHWESTERLY FLOW  
AND COOLER PATTERN THEN LOOKS TO SET UP ACROSS THE GREAT LAKES  
FOR THE SECOND HALF OF NEXT WEEK. LONG-RANGE MODELS ALSO SHOW  
(FAIRLY CONSISTENTLY) A SURFACE HIGH PRESSURE SET UP OVER THE  
REGION THROUGH THE END OF THE WEEK, WHICH WOULD SUPPORT NEAR-  
NORMAL IF NOT SLIGHTLY BELOW NORMAL TEMPS.  
 
WAGNER  
 

 
   
AVIATION
 
 
ISSUED 253 PM CDT FRI JUL 25 2025  
 
SOME LINGERING LOW CLOUDS WITH POCKETS OF MVFR CEILINGS ALONG  
THE LAKESHORE (KMKE AND KENW) AND ACROSS SOUTH-CENTRAL WI  
(KJVL), BUT CONTINUE TO SEE CEILINGS IMPROVE AND SCATTER OUT  
THIS AFTERNOON. INFLUENCE FROM THE HIGH PRESSURE OVER THE UPPER  
GREAT LAKES WILL CONTINUE THROUGH THE EVENING WITH VFR  
CONDITIONS AND LIGHT AND VARIABLE WINDS. WILL GRADUALLY SEE A  
SOUTHERLY WIND SHIFT TONIGHT INTO SATURDAY AS THE FRONTAL  
BOUNDARY ACROSS IL GRADUALLY LIFTS NORTHWARD INTO SOUTHERN WI.  
WILL BE THE FOCUS FOR ISOLATED SHOWER/STORM ACTIVITY OVERNIGHT,  
MAINLY ALONG THE WI/IL BORDER. HOWEVER, THERE WILL BE  
ADDITIONAL, MORE SCATTERED AND WIDESPREAD SHOWERS WITH A FEW  
EMBEDDED THUNDERSTORMS FOR THE FIRST HALF OF THE DAY SATURDAY,  
GENERALLY FOR AREAS SOUTH OF LINE FROM PORT WASHINGTON TO  
DARLINGTON. WILL SEE LOWER MVFR CEILINGS (<3KFT) MOVE IN THROUGH  
THE MORNING, BUT ACCOMPANYING ANY SHOWERS AND STORMS SATURDAY  
WILL BE LOWER VISIBILITY AND LOWER CEILINGS (<2KFT). SHOWER AND  
STORM CHANCES DIMINISH LATER SATURDAY AFTERNOON AND EVENING WITH  
LIGHT SOUTHERLY WINDS LINGERING ACROSS THE AREA.  
 
WAGNER  
 

 
   
MARINE
 
 
ISSUED 251 PM CDT FRI JUL 25 2025  
 
HIGH PRESSURE CENTERED OVER LAKE SUPERIOR AND NORTHERN LAKE  
MICHIGAN WILL GRADUALLY SLIDE EAST TONIGHT. THEN A FRONTAL  
BOUNDARY STALLED SOUTH OF LAKE MICHIGAN THIS AFTERNOON IS  
EXPECTED TO GRADUALLY LIFT NORTHWARD OVERNIGHT INTO SATURDAY.  
WILL SEE LIGHTER NORTH AND EASTERLY WINDS NORTH OF THE BOUNDARY,  
BUT WILL BEGIN TO SHIFT MORE SOUTHERLY BEHIND IT. LIGHT  
SOUTHERLY WINDS WILL PREVAIL BY SATURDAY AFTERNOON/EVENING  
ACROSS ALL OF LAKE MICHIGAN. WILL CONTINUE TO SEE LIGHT TO  
OCCASIONALLY MODERATE SOUTHERLY WINDS PREVAIL THROUGH THE  
WEEKEND INTO EARLY NEXT WEEK. THERE WILL BE A FEW WINDOWS FOR  
SHOWER AND THUNDERSTORMS TO TRACK ACROSS THE LAKE  
TONIGHT/SATURDAY AND AGAIN SUNDAY NIGHT INTO MONDAY AND AGAIN  
MIDWEEK. MAY SEE MORE VARIABLE WINDS ACCOMPANYING ANY STORM  
COMPLEX THAT TRAVERSES THE LAKE THROUGH EARLY NEXT WEEK.  
 
WAGNER  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
LM...NONE.  

 
 

 
 
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