730  
FXUS63 KMKX 301151  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
651 AM CDT THU APR 30 2026  
   
KEY MESSAGES
 
 
- FROST AND PATCHY FOG WILL BURN OFF WITHIN THE NEXT FEW HOURS.  
 
- ADDITIONAL FROST EXPECTED TONIGHT AND FRIDAY NIGHT, WITH  
FREEZING TEMPERATURES POSSIBLE AWAY FROM LAKE MICHIGAN.  
 
- POP-UP SHOWERS CONTINUE DURING THE AFTERNOON HOURS TODAY AND  
FRIDAY. SOME GRAUPEL COULD MIX IN WITH THE RAIN.  
 
- ADDITIONAL SHOWER & THUNDERSTORM CHANCES SUNDAY NIGHT THROUGH  
THE MIDDLE OF NEXT WEEK.  
 

 
   
UPDATE
 
 
ISSUED 652 AM CDT THU APR 30 2026  
 
PATCHY FOG IS BECOMING LOCALLY DENSE IN LOW LYING AREAS THIS  
MORNING, BUT WILL BURN OFF WITHIN THE NEXT HOUR OR TWO AS  
TEMPERATURES RISE. A FOG ADVISORY HAS BEEN ISSUED TO ACCOUNT FOR  
THIS THREAT FOR WASHINGTON, JEFFERSON, WAUKESHA, RACINE,  
KENOSHA, AND WALWORTH COUNTIES. WIDESPREAD FROST HAS BEEN  
OBSERVED ACROSS INLAND AREAS AWAY FROM FAR SOUTHERN WISCONSIN  
WHERE CLOUD COVER HAS LINGERED OVERNIGHT, BUT WILL ALSO BURN OFF  
WITHIN THE NEXT FEW HOURS. A WAVE OF SHOWERS WILL PROGRESS  
EASTWARD THROUGH THE DAY AS A SHORTWAVE MOVES THROUGH ONCE  
AGAIN, WITH SHOWERS BECOMING MORE NUMEROUS DURING THE AFTERNOON  
HOURS. AN ISOLATED GRAUPEL PELLET IS STILL POSSIBLE.  
 
MH  
 

 
   
SHORT TERM
 
 
ISSUED 1145 PM CDT WED APR 29 2026  
 
REST OF TONIGHT THROUGH SATURDAY NIGHT:  
 
SYNOPSIS/MESOANALYSIS: A BROAD UPPER TROUGH WILL REMAIN ENTRENCHED  
ACROSS THE WESTERN GREAT LAKES THROUGH THE FIRST HALF OF THIS  
WEEKEND. EMBEDDED SMALL-SCALE PERTURBATIONS WILL PROGRESS THROUGH  
THE BROAD AREA OF TROUGHING, COMBINING WITH DAYTIME HEATING TO  
SUPPORT ADDITIONAL PERIODS OF POP-UP RAIN SHOWERS ACROSS SOUTHERN  
WISCONSIN BOTH THURSDAY AND FRIDAY AFTERNOON. HAZARDS AREN'T  
EXPECTED IN ANY ADDITIONAL SHOWER DEVELOPMENT, THOUGH A FEW GRAUPEL  
PELLETS COULD MIX IN WITH THE RAIN DROPS. CONDITIONS WILL DRY OUT ON  
SATURDAY AS SHORTWAVE RIDGING MOVES IN FROM THE NORTHERN PLAINS.  
BROAD HIGH PRESSURE OVER THE CANADIAN GREAT PLAINS WILL MAINTAIN  
NORTH-NORTHWEST BREEZES ACROSS THE REGION THROUGH FRIDAY NIGHT,  
RESULTING IN CONTINUED BELOW NORMAL TEMPERATURES. ANTICIPATE AREAS  
OF FROST DEVELOPMENT DURING THE OVERNIGHT PERIODS TONIGHT, AND ONCE  
AGAIN ON THURSDAY NIGHT AND FRIDAY NIGHT. FROST ADVISORIES REMAIN IN  
EFFECT FOR PARTS OF SOUTHERN WISCONSIN TONIGHT, WITH ADDITIONAL  
HEADLINES ANTICIPATED THROUGH THE END OF THE WEEK. BE SURE TO BRING  
ANY COLD-SENSITIVE PLANTS INDOORS DURING OVERNIGHT PERIODS.  
 
REST OF TONIGHT: ANY LAST SHOWERS WILL PUSH OUT OF EAST-CENTRAL  
WISCONSIN AFTER MIDNIGHT, GIVING WAY TO AT LEAST PARTLY CLEAR SKIES  
ACROSS SOUTHERN WISCONSIN. CLEARING SKIES WILL COMBINE WITH LIGHT  
SURFACE WINDS TO COOL OVERNIGHT LOWS. TEMPERATURES IN THE LOW-MID  
30S WILL COMBINE WITH THE AFOREMENTIONED LIGHT SURFACE WINDS TO  
SUPPORT AREAS OF FROST, WITH THE MOST WIDESPREAD POTENTIAL GENERALLY  
EXPECTED TO THE NORTH OF I-94 AND WEST OF I-41. EXPECTED COVERAGE OF  
MORE WIDESPREAD FROST POTENTIAL HAS INCREASED IN THE EVENING  
FORECAST UPDATE, WITH FOND DU LAC, DODGE, WASHINGTON, JEFFERSON,  
DANE AND WAUKESHA COUNTIES BEING ADDED TO THE PRE-EXISTING FROST  
ADVISORY BETWEEN 12 AM AND 8 AM. BE SURE TO MOVE ANY COLD-SENSITIVE  
PLANTS INSIDE IN ANY OF THESE LOCATIONS. ONGOING IN CURRENT OBS,  
BRIEF POCKETS OF SHALLOW FOG COULD PRECEDE FROST DEVELOPMENT,  
WITH THE EXPECTATION FOR A RELATIVELY QUICK TRANSITION TO FROST  
AS A VERY SHALLOW NEAR-SURFACE MOIST LAYER DEPOSITS OUT.  
 
THURSDAY: FAIR-WEATHER CUMULUS CLOUDS WILL QUICKLY BLOSSOM FROM LATE  
MORNING INTO THE AFTERNOON AS THE SURFACE HEATS BENEATH AN OVERALL  
COLD COLUMN OVERHEAD. WITH TIME, EXPECT THAT SAID CUMULUS WILL GROW  
DEEP ENOUGH TO SUPPORT HIT & MISS SHOWER DEVELOPMENT ACROSS THE  
AREA. NOT ANTICIPATING ANY HAZARDS IN THIS ACTIVITY, THOUGH AN  
OVERLAP OF VERY WEAK MUCAPE & VERY COLD TEMPERATURES ALOFT COULD  
SUPPORT SOME GRAUPEL PELLETS IN ANY DEEPER UPDRAFTS. NO IMPACTS ARE  
ANTICIPATED.  
 
THURSDAY NIGHT: EXPECTING COLDER OVERNIGHT LOWS RELATIVE TO TONIGHT,  
WITH ANOTHER ROUND OF FROST DEVELOPMENT FORECAST OVER SOUTHERN  
WISCONSIN. ANTICIPATING THAT WIDESPREAD FROST COVERAGE WILL BE  
HIGHER COMPARED TO TONIGHT, WITH A LARGER PART OF THE AREA LIKELY  
NEEDING A FROST ADVISORY. WILL BE ADDRESSING THE NEED FOR THURSDAY  
NIGHT FROST/FREEZE HEADLINES IN THE THURSDAY AFTERNOON FORECAST  
UPDATE.  
 
FRIDAY: ANOTHER ROUND OF DIURNAL RAIN SHOWERS IS FORECAST, THOUGH  
COVERAGE MIGHT BE A TOUCH LOWER COMPARED TO THURSDAY. SOME GRAUPEL  
PELLETS COULD MIX IN WITH RAIN ONCE MORE GIVEN STILL VERY COLD  
TEMPERATURES OVERHEAD.  
 
FRIDAY NIGHT: ANTICIPATING ANOTHER ROUND OF WIDESPREAD FROST  
DEVELOPMENT, WITH ADDITIONAL FROST HEADLINES LIKELY. DETAILS  
REGARDING THE PRECISE TIMING & PLACEMENT OF HEADLINES WILL BE  
REFINED IN COMING FORECASTS.  
 
QUIGLEY  
 

 
   
LONG TERM
 
 
ISSUED 1145 PM CDT WED APR 29 2026  
 
SUNDAY THROUGH WEDNESDAY:  
 
SYNOPSIS: SHORTWAVE RIDGING WILL BE SHORT-LIVED/CONFINED TO THE DAY  
ON SUNDAY, WITH A RENEWED AREA OF MEAN TROUGHING BECOMING  
ESTABLISHED FROM THE HUDSON BAY TO THE WESTERN GREAT LAKES THROUGH  
MOST OF THE LONG TERM PERIOD. POSITIONING OF THE TROUGH WILL PLACE  
SOUTHERN WISCONSIN IN LINE FOR ADDITIONAL SHORTWAVE & SURFACE  
FRONTAL PASSAGES SUNDAY NIGHT THROUGH THE MIDDLE OF NEXT WEEK, WITH  
EACH SHORTWAVE/SURFACE FRONT PASSAGE BRINGING CHANCES FOR ADDITIONAL  
SHOWERS AND THUNDERSTORMS. NEAR OR SLIGHTLY BELOW NORMAL  
TEMPERATURES & ONLY MODEST MOISTURE RETURNS ARE EXPECTED TO KEEP  
THUNDERSTORMS BELOW SEVERE LEVELS, THOUGH TRENDS WILL CONTINUE TO BE  
MONITORED OVER COMING FORECASTS.  
 
SUNDAY THROUGH MONDAY: CURRENTLY ANTICIPATING A PAIR OF SHOWER &  
THUNDERSTORM CHANCES ACROSS SOUTHERN WISCONSIN AS TWO SHORTWAVES &  
SURFACE FRONTS MOVE THROUGH THE WESTERN GREAT LAKES. CURRENTLY  
FAVORED PERIODS ARE SUNDAY AFTERNOON/EVENING AND MONDAY  
EVENING/NIGHT, WITH PRECISE TRENDS BEING REFINED IN COMING  
FORECASTS. MUCAPE WILL BE SUFFICIENT FOR A FEW THUNDERSTORMS IN EACH  
BATCH OF ACTIVITY, WITH CURRENT PROGS FROM THE LREF IMPLYING LOW  
ENOUGH VALUES TO KEEP ACTIVITY SUB-SEVERE. WILL NEVERTHELESS BE  
MONITORING TRENDS OVER COMING UPDATES.  
 
TUESDAY INTO WEDNESDAY: ADDITIONAL SHOWERS & STORMS ARE FORECAST AS  
ANOTHER UPPER WAVE AND SURFACE FRONT MOVE THROUGH THE REGION. HAVE  
LARGELY MAINTAINED PRECIP FORECASTS FROM THAT OF THE NBM, WHICH  
DEPICTS BROAD 20-40% PROBABILITIES OVER MOST OF THIS TIME FRAME.  
MAINTAINED THESE PROBABILITIES NOT BECAUSE IT WILL BE RAINING FOR  
THE ENTIRETY OF THE TUESDAY-WEDNESDAY TIME FRAME, BUT RATHER THAT  
HIGH SPREAD REMAINS AMONGST GLOBAL GUIDANCE REGARDING THE PRECISE  
TIMING OF THE UPPER WAVE AND FRONTAL PASSAGE. ANTICIPATE THAT THE  
RANGE OF MENTIONABLE PRECIP PROBS WILL DECREASE AS TIMING/PLACEMENT  
TRENDS CLARIFY THROUGH THIS WEEKEND.  
 
QUIGLEY  
 

 
   
AVIATION
 
 
ISSUED 652 AM CDT THU APR 30 2026  
 
PATCHY FOG WITH LOCALIZED AREAS OF DENSE FOG IN LOW LYING AREAS  
HAS DEVELOPED ACROSS PORTIONS OF SOUTHEASTERN WISCONSIN, WITH  
LOCALLY DENSE LOW- LYING FOG. FOG WILL BURN OFF WITHIN THE NEXT  
COUPLE HOURS. EXPECTING ISOLATED SHOWERS TO PROGRESS THROUGH THE  
REGION THIS MORNING, BECOMING SCATTERED TO WIDESPREAD THIS  
AFTERNOON. EXPECTING VFR CONDITIONS TO CONTINUE WITHIN THESE  
SHOWERS. SHOWERS WILL TAPER OFF WEST TO EAST OVERNIGHT. A FEW  
MVFR CEILINGS COULD WORK THEIR WAY INTO SOUTHEASTERN WISCONSIN  
OFF LAKE MICHIGAN LATE TONIGHT, BUT OTHERWISE EXPECT VFR  
CONDITIONS TO CONTINUE.  
 
GENERALLY NORTHWESTERLY WINDS THROUGHOUT TODAY, SHIFTING TO  
BECOME NORTHERLY TONIGHT, THEN BECOMING LIGHT AND VARIABLE LATE  
TONIGHT INTO FRIDAY MORNING.  
 
MH  
 

 
   
MARINE
 
 
ISSUED 1145 PM CDT WED APR 29 2026  
 
WIDESPREAD GALES ARE NOT EXPECTED THROUGH THE DURATION OF THE PERIOD  
ACROSS THE OPEN WATERS OF LAKE MICHIGAN. CURRENTLY NORTH-NORTHWEST  
WINDS WILL CONTINUE THROUGH THE END OF THE WEEK AS 1002 MB LOW  
PRESSURE SHIFTS INTO THE CANADIAN MARITIME PROVINCES & 1022 MB HIGH  
PRESSURE BUILDS INTO THE NORTHERN GREAT PLAINS. WINDS WILL TREND  
SOUTH-SOUTHWESTERLY SATURDAY INTO SUNDAY AS THE AFOREMENTIONED AREA  
OF HIGH PRESSURE MOVES INTO THE OHIO RIVER VALLEY AND 1000 MB LOW  
PRESSURE FORMS OVER THE HUDSON BAY. WINDS WILL BRIEFLY VEER WESTERLY  
SUNDAY NIGHT INTO MONDAY AS A WEAK COLD FRONT CROSSES LAKE MICHIGAN.  
SHOWERS AND A FEW THUNDERSTORMS WILL ACCOMPANY THE FRONT, WITH  
SEVERE WEATHER NOT ANTICIPATED AT THIS TIME.  
 
A SECOND AREA OF STRONGER LOW PRESSURE NEAR 992 MB WILL DEVELOP OVER  
THE LAKE SUPERIOR VICINITY DURING THE DAY MONDAY, ULTIMATELY  
SHIFTING TOWARD THE SOUTHERN HUDSON BAY AND QUEBEC ON TUESDAY.  
PROGRESSION OF THE LOW WILL ALLOW WINDS TO TREND WEST-SOUTHWESTERLY  
MONDAY NIGHT THROUGH WEDNESDAY. A COLD FRONT IS FORECAST TO CROSS  
THE OPEN WATERS WEDNESDAY AFTERNOON, BRINGING A NORTHWEST WIND  
SHIFT. ADDITIONAL PERIODS OF SHOWERS AND EMBEDDED STORMS ARE  
FORECAST SUNDAY NIGHT INTO THE MIDDLE OF NEXT WEEK, WITH WIDESPREAD  
SEVERE THUNDERSTORMS NOT EXPECTED AT THIS TIME.  
 
WIDESPREAD SMALL CRAFT ADVISORY CONDITIONS ARE NOT EXPECTED THROUGH  
THE DURATION OF THE PERIOD IN NEARSHORE ZONES. WEST-NORTHWEST WINDS  
WILL CONTINUE TONIGHT THROUGH THE END OF THE WEEK AS HIGH PRESSURE  
BUILDS IN FROM THE NORTHERN GREAT PLAINS. WINDS WILL TREND WEST-  
SOUTHWESTERLY THIS WEEKEND AS LOW PRESSURE DEVELOPS NEAR THE HUDSON  
BAY. WINDS WILL TREND WESTERLY SUNDAY NIGHT INTO MONDAY MORNING AS A  
WEAK SURFACE FRONT CROSSES LAKE MICHIGAN. WEST-SOUTHWEST WINDS  
RETURN MONDAY AFTERNOON INTO WEDNESDAY AS A SECOND SURFACE FRONT  
APPROACHES LAKE MICHIGAN FROM THE WEST. PERIODS OF SHOWERS &  
EMBEDDED THUNDERSTORMS ARE FORECAST SUNDAY NIGHT INTO MONDAY, MONDAY  
EVENING, AS WELL AS TUESDAY INTO WEDNESDAY. SEVERE WEATHER IS NOT  
ANTICIPATED AT THIS TIME, THOUGH TRENDS WILL CONTINUE TO BE  
MONITORED.  
 
QUIGLEY  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...FROST ADVISORY...WIZ046-WIZ047-WIZ051-WIZ056-WIZ057-WIZ058-  
WIZ059-WIZ063-WIZ064-WIZ065 UNTIL 8 AM THURSDAY.  
 
DENSE FOG ADVISORY...WIZ059-WIZ064-WIZ065-WIZ070-WIZ071-WIZ072  
UNTIL 9 AM THURSDAY.  
 
LM...NONE.  

 
 

 
 
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