733  
FXUS63 KMKX 221600  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
1100 AM CDT TUE JUL 22 2025  
   
KEY MESSAGES
 
 
- HIGH SWIM RISKS DUE TO BUILDING WAVES AND DANGEROUS CURRENTS  
FOR OZAUKEE AND SHEBOYGAN COUNTY BEACHES TODAY. MODERATE SWIM  
RISK FOR MILWAUKEE AND RACINE COUNTY BEACHES AS WELL.  
 
- SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE TONIGHT INTO  
EARLY WEDNESDAY MORNING.  
 
- DANGEROUS HEAT BUILDING INTO THE STATE WEDNESDAY AND  
THURSDAY. HEAT INDICES OF 100 TO 107 DEGREES ARE EXPECTED. AN  
EXTREME HEAT WATCH IS IN EFFECT STARTING WEDNESDAY.  
 
- INCREASED SHOWER AND THUNDERSTORM CHANCES (>50%) FOR THURSDAY  
WITH PERIODIC CHANCES FRIDAY INTO SATURDAY.  
 

 
   
UPDATE
 
 
ISSUED 1040 AM CDT TUE JUL 22 2025  
 
HIGH SWIM RISK IS NOW IN EFFECT FOR THE SHORELINES OF SHEBOYGAN  
AND OZAUKEE COUNTIES FOR WAVES TO 4 FEET FROM BREEZY ONSHORE  
WINDS. OTHERWISE QUIET CONDITIONS ARE EXPECTED THE REST OF  
TODAY. INTO THE EVENING, PARTICULARLY LATE, WE MAY SEE SOME  
STORMS/SHOWERS PUSH IN FROM AN MCV FEATURE SLIDING IN OVERNIGHT  
FROM THE PLAINS. NOW THIS OVERNIGHT FEATURE IS VERY UNCERTAIN  
WITH MOST CAMS KEEPING THINGS DRY UNTIL AT LEAST EARLY WEDNESDAY  
MORNING. THEN MOST CAMS BEGIN TO DEVELOP SOME CONVECTION  
PRIMARILY NORTH OF THE CWA LATER WEDNESDAY THOUGH WE CERTAINLY  
COULDN'T RULE OUT SOME CONVECTION FURTHER SOUTH INTO THE AREA.  
 
STILL TRYING TO NAIL DOWN SOME OF THE STORM TIMING AND  
LOCATIONS FOR TOMORROW TO BETTER FIGURE OUT HOW THE HEAT WILL  
PLAY OUT TOMORROW BUT IT APPEARS MUCH MORE CERTAIN FURTHER SOUTH  
AND ESPECIALLY SOUTHEAST. HEAT ADVISORY LOOKS LIKELY FOR MOST  
IF NOT ALL OF THE CWA FOR TOMORROW.  
 
KUROSKI  
 

 
   
SHORT TERM
 
 
ISSUED 352 AM CDT TUE JUL 22 2025  
 
TODAY THROUGH WEDNESDAY:  
 
SOUTHEAST WINDS WILL INCREASE TODAY AS LOW PRESSURE APPROACHES  
FROM THE NORTHERN PLAINS AND HIGH PRESSURE HOLDS STEADY OVER THE  
UPPER GREAT LAKES. THE STEADY WINDS OVER A LONG FETCH WILL  
PRODUCE HIGH WAVES IN THE NEARSHORE AREA AND ALONG THE SHORELINE  
OF OZAUKEE AND SHEBOYGAN COUNTIES. A HIGH SWIM RISK IS EXPECTED  
THERE TODAY AND A BEACH HAZARDS STATEMENT IS IN EFFECT. WINDS  
WILL EASE A LITTLE TONIGHT AND THEN RAMP UP OUT OF THE SOUTH ON  
WEDNESDAY. ANOTHER HIGH SWIM RISK IS EXPECTED NORTH OF  
MILWAUKEE.  
 
TODAY WILL BE A TRANSITION DAY FROM OUR DRY EASTERLY FLOW TO OUR  
WARM AND MOIST SOUTHERLY FLOW. THE WEATHER IN SOUTHERN WI WILL  
REMAIN DRY TODAY, ALTHOUGH THE CLOUD COVER WILL BE HIGHER THAN  
THE PREVIOUS DAYS DUE TO THE LOW LEVEL MOISTURE ADVECTION.  
DEWPOINTS WILL RISE INTO THE LOWER 70S FOR WESTERN AREAS BY LATE  
AFTERNOON.  
 
THE 00Z MODELS INTRODUCED A STORM COMPLEX THAT SHOULD DEVELOP  
ALONG A REMNANT MCV AS IT DRIFTS OVER CENTRAL IOWA THIS  
AFTERNOON. THERE IS REMARKABLE MODEL CONSENSUS THAT THE STORM  
COMPLEX WOULD DRIFT INTO SOUTH CENTRAL WI AROUND MIDNIGHT  
TONIGHT AND WEAKEN/DIMINISH AS IT TRACKS THROUGH SOUTHERN WI  
OVERNIGHT. BESIDES THE FORCING FROM THE MCV, THERE IS WEAK  
SYNOPTIC SUPPORT WITHIN THE VERY SOUTHERN EDGE OF THE LOW LEVEL  
JET, WARM AIR ADVECTION, AND UPPER JET DIVERGENCE. THE 06Z RUN  
OF THE NAM AND NAMNEST BACKED OFF THE CONVECTIVE LOOK A BIT FOR  
OUR AREA, SO WE WILL HAVE TO SEE HOW THE 12Z MODELS LOOK.  
 
ANY ESTABLISHED STRONG/SEVERE STORMS UPSTREAM THAT TRACK INTO  
SOUTH CENTRAL WI LATER TONIGHT WOULD HAVE A BRIEF POTENTIAL FOR  
GUSTY WINDS. THE FORCING DROPS OFF AS THE SYSTEM WOULD GET INTO  
SOUTHEAST WI EARLY WEDNESDAY MORNING.  
 
WEDNESDAY TEMPERATURES MAY BE IN JEOPARDY IF THIS SYSTEM PANS OUT  
AND BRINGS EXTENSIVE CLOUD COVER FOR THE FIRST HALF OF THE DAY.  
HOWEVER, THE ROBUST AREA OF HEAT AND HUMIDITY WILL QUICKLY PUSH  
INTO SOUTHERN WI DURING THE AFTERNOON. THUS THERE IS STILL  
UNCERTAINTY AND NO NEED TO MAKE CHANGES TO THE EXTREME HEAT  
WATCH THAT IS IN EFFECT.  
 
CRONCE  
 
WEDNESDAY SYNOPSIS:  
 
AS BROAD SURFACE HIGH PRESSURE CONTINUES TO EDGE EASTWARD INTO THE  
ATLANTIC OCEAN ON WEDNESDAY, A SURFACE PRESSURE TROUGH DEVELOPS TO  
OUR WEST, SPANNING FROM NEBRASKA TO CENTRAL MN AND NORTHERN WI.  
THE RESULTING SOUTHWESTERLY WAA WILL ALLOW THE UPPER LEVEL RIDGE  
TO CONTINUE TO BUILD, WITH DAYTIME HIGHS SOARING TO THE LOW TO MID  
90S. THE SOUTHWESTERLY SURFACE FLOW IS ALSO EXPECTED TO COMPLETELY  
WASH OUT THE LAKE BREEZE, SPREADING THE HEAT TO ALL AREAS.  
COUPLED WITH DEWPOINTS IN THE MID 70S, MAXIMUM HEAT INDICES IN  
THE 103 TO 107 DEGREE RANGE ARE EXPECTED WEDNESDAY.  
 
SHORTWAVE TROUGHS RIDING THE CREST OF THE RIDGE ARE EXPECTED TO  
TRIGGER THUNDERSTORMS ALONG THE SURFACE PRESSURE TROUGH TO OUR  
NORTH AND WEST LATE WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING.  
OUR FORECAST FEATURES 15% PRECIP CHANCES IN OUR NORTHWEST AREA  
OF COUNTIES (SAUK, MARQUETTE, GREEN LAKE) TO ACCOUNT FOR THE  
OFF CHANCE OF THESE STORMS BECOMING PROGRESSIVE AND MOVING OFF  
OF THE SURFACE PRESSURE TROUGH.  
 
SHEPPARD  
 

 
   
LONG TERM
 
 
ISSUED 352 AM CDT TUE JUL 22 2025  
 
THURSDAY THROUGH MONDAY:  
 
THE AFOREMENTIONED SURFACE PRESSURE TROUGH GRADUALLY SAGS  
SOUTHWARD INTO THURSDAY, WITH CONTINUED SOUTHWEST WINDS AHEAD OF  
IT REMOVING THE LAKE BREEZE ONCE AGAIN. THIS SETUP IS EXPECTED  
TO ALLOW THE HEAT TO REMAIN IN PLACE THURSDAY, HENCE THE EXTREME  
HEAT WATCH IS ALLOWED TO CONTINUE. THUNDERSTORMS ARE EXPECTED  
TO GRADUALLY EVOLVE ALONG THE BOUNDARY AS IT SAGS SOUTHWARDS,  
WITH SLOW / NEARLY STATIONARY CORFIDI VECTORS AND ECMWF AND GFS  
PWAT VALUES JUST OVER 2 INCHES. OUR BEST GUESS IS FOR CONVECTION  
TO DELAY LONG ENOUGH TO ALLOW DIURNAL HEATING TO RUN IT'S  
COURSE (HEAT INDICES UP TO 105, WITH THE HIGHEST POTENTIAL  
TOWARDS SOUTHEASTERN WISCONSIN) FOLLOWED BY AREA-WIDE CHANCES  
FOR THUNDERSTORMS LATER THURSDAY AFTERNOON INTO THURSDAY  
EVENING. THAT SAID, THE ARRIVAL TIMES COULD CHANGE, AND MODELS  
DO RESOLVE SOME PVA AHEAD OF AN APPROACHING 500MB SHORTWAVE  
ARRIVING CLOSER TO MID- THURSDAY. THE INGREDIENTS FOR A FEW  
STRONGER THUNDERSTORMS AND LOCALIZED HEAVY RAINFALL ARE PRESENT,  
MORE WILL BECOME CLEARER ON SUBSEQUENT FORECAST ITERATIONS.  
 
THE SURFACE PRESSURE TROUGH / BAROCLINIC ZONE IS EXPECTED TO SAG  
FURTHER SOUTH (INTO ILLINOIS) AND DILUTE INTO FRIDAY, RESULTING IN  
REDUCED (~30%) CHANCES FOR SHOWERS AND THUNDERSTORMS. MOST MODELS  
DROP THE MAJORITY OF QPF TO THE SOUTH OF US ON FRIDAY, THOUGH  
SURFACE TEMP / DEWPOINT OUTPUT ON ENSEMBLE MEMBERS DO HINT AT THE  
POSSIBILITY FOR REMNANT OUTFLOW BOUNDARIES OR THE SFC PRESSURE  
TROUGH TO WAFFLE BACK NORTHWARD, WITH A FEW SHOWERS /  
THUNDERSTORMS TO SPARE IN OUR CWA. PARTIAL CLOUD COVER AND  
POTENTIAL FOR A LAKE BREEZE SHOULD WORK TOGETHER TO SLIGHTLY  
REDUCE THE HEAT ON FRIDAY, THOUGH THE HUMIDITY SHOULD REMAIN.  
 
FROM A SYNOPTIC PERSPECTIVE, SATURDAY AND SUNDAY ARE LOOKING  
RELATIVELY QUIET (WEAK SURFACE WIND FLOW, SOME LAKE BREEZE  
POTENTIAL, NOT MUCH OF ANY UPPER-LEVEL DYNAMICS TO SPEAK OF),  
THOUGH LINGERING WARMTH AND HUMIDITY MAY BE SUFFICIENT FOR AIRMASS  
THUNDERSTORMS, AND MODELS DO KEEP THE SUBTROPICAL JET STREAM  
CLOSE BY, WITH SOME POTENTIAL FOR A WEAK PERTURBATION RIPPLING  
THROUGH (HENCE THE BROAD-BRUSHED 10-20% POPS). A SIMILAR STORY  
INTO MONDAY, WITH SLIGHTLY HIGHER CHANCES OF A PERTURBATION IN THE  
UPPER-LEVEL FLOW.  
 
SHEPPARD  
 

 
   
AVIATION
 
 
ISSUED 1055 AM CDT TUE JUL 22 2025  
 
MVFR CIGS HAVE LARGELY ENDED ACROSS THE AREA LIFTING TO VFR AND  
GRADUALLY DISSIPATING ACROSS THE REGION. VFR CONDITIONS WILL  
CONTINUE THROUGH THE REMAINDER OF THE DAY BEFORE A FEATURE  
PUSHES IN FROM THE WEST OVERNIGHT THAT WILL LIKELY BRING MVFR  
CIGS BACK TO THE REGION FOR AT LEAST WESTERN PORTIONS OF THE  
STATE. THIS MAY LINGER ACROSS CENTRAL WI THROUGH WEDNESDAY BUT  
LIKELY CLEARING DURING THE MORNING HOURS ACROSS MUCH OF SOUTHERN  
WI. OTHERWISE EXPECT MODEST SOUTH TO SOUTHEAST WINDS TODAY AND  
MORE BREEZY SOUTH TO SOUTHWEST WINDS WEDNESDAY.  
 
KUROSKI  
 

 
   
MARINE
 
 
ISSUED 352 AM CDT TUE JUL 22 2025  
 
WINDS WILL INCREASE TO AROUND 20 KNOTS AND VEER SOUTHEAST TODAY  
AS LOW PRESSURE APPROACHES MINNESOTA FROM THE CENTRAL PLAINS.  
BREEZY SOUTHERLY WINDS UP TO 30 KT ARE EXPECTED WEDNESDAY. THERE  
IS A SMALL CRAFT ADVISORY IN EFFECT FOR THE DAYTIME HOURS TODAY  
DUE TO ELEVATED WAVES WITH PERSISTENT SOUTHEAST WINDS AND LARGE  
FETCH. WINDS AND WAVES WILL DIMINISH A BIT TONIGHT, BUT INCREASE  
OUT OF THE SOUTH ON WEDNESDAY. GUSTS UP TO 25 KT IN THE  
NEARSHORE NORTH OF MILWAUKEE SEEM PROBABLE AND ANOTHER SMALL  
CRAFT ADVISORY SHOULD BE NEEDED.  
 
THERE ARE CHANCES FOR STORMS STARTING WEDNESDAY MORNING AND  
CONTINUING THROUGH FRIDAY ALONG A FRONTAL BOUNDARY. INITIALLY,  
WEDNESDAY INTO THURSDAY MORNING, EXPECT THE FRONT TO REMAIN  
STATIONARY ACROSS THE NORTHERN HALF OF THE LAKE. THURSDAY  
AFTERNOON THROUGH FRIDAY, EXPECT THE FRONT TO PUSH SOUTHWARD,  
BRINGING STORMS SOUTHEASTWARD THROUGH THE REMAINDER OF THE OPEN  
WATERS. A LOW PRESSURE TROUGH WILL DROP THROUGH THE AREA  
THURSDAY NIGHT INTO FRIDAY, SHIFTING WINDS TO WESTERLY.  
 
CRONCE  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060 UNTIL 7 PM TUESDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644 UNTIL 7 PM TUESDAY.  
 

 
 

 
 
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