110  
FXUS63 KMKX 191058 AAA  
AFDMKX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
558 AM CDT SAT SEP 19 2026  
   
KEY MESSAGES
 
 
- FIRST ROUND OF HEAVY RAINFALL HAS PUSHED SOUTH OF THE AREA,  
WITH LINGERING MODERATE RAINFALL INTO THIS MORNING. AREA OF  
HEAVIER RAIN TO THE WEST SHOULD REMAIN WEST AND SOUTHWEST OF  
THE AREA INTO THIS MORNING. MAY SEE A BRIEF LULL BEFORE THE  
NEXT ROUND MOVES IN BY MIDDAY/EARLY THIS AFTERNOON.  
 
- ADDITIONAL STORM DEVELOPMENT IS POSSIBLE THIS AFTERNOON,  
PARTICULARLY ALONG AND SOUTH OF INTERSTATE 94. ADDITIONAL  
HEAVY DOWNPOURS AND FLOODING IMPACTS WOULD BE THE MAIN  
CONCERNS, WITH AN ISOLATED STRONG STORM POSSIBLE NEAR THE  
WISCONSIN/ILLINOIS BORDER.  
 
- PROLONGED PERIOD OF HIGH SWIMMING RISK CONDITIONS CONTINUES  
INTO TUESDAY AT ALL LAKE MICHIGAN BEACHES, AND MAY NEED TO BE  
EXTENDED INTO WEDNESDAY EVENING.  
 
- OFF AND ON CHANCES FOR LIGHTER RAIN SUNDAY INTO MONDAY.  
TRENDING DRIER TUESDAY ONWARD.  
 

 
   
UPDATE
 
 
ISSUED 558 AM CDT SAT SEP 19 2026  
 
THE FIRST ROUND OF HEAVY RAINFALL AS PUSHED SOUTH OF THE AREA,  
WITH LINGERING MODERATE RAIN OVER MOST OF THE AREA. THIS  
ACTIVITY SHOULD LINGER INTO MIDDLE MORNING WITH LINGERING WARM  
AIR ADVECTION, BEFORE A POSSIBLE LULL IN THE ACTIVITY BY LATER  
THIS MORNING OCCURS.  
 
THERE ARE ADDITIONAL SHOWERS AND STORMS WITH HEAVY RAINFALL  
REMAINING TO THE WEST AND SOUTHWEST OF THE AREA EARLY THIS  
MORNING, CLOSELY TIED TO THE SOUTHWESTERLY LOW LEVEL JET NOSE  
AND FRONTOGENESIS RESPONSE NEAR 850 MB. THESE FEATURES ARE  
EXPECTED TO GRADUALLY VEER SOUTHEAST THROUGH THE MORNING, WHICH  
SHOULD MAINLY MISS OR JUST CLIP FAR SOUTHWEST PARTS OF THE  
FORECAST AREA. WILL CONTINUE TO MONITOR FOR FLASH FLOODING AND  
OTHER FLOODING IMPACTS IN THIS AREA INTO THIS MORNING.  
 
A 500 MB SHORTWAVE TROUGH HELPING ALONG AN AREA OF SHOWERS AND A  
FEW STORMS IN WESTERN IOWA SHOULD PUSH EAST NORTHEAST INTO THE  
AREA BY MIDDAY INTO THE AFTERNOON. THIS FEATURE, ALONG WITH THE  
CLOSE PROXIMITY OF THE SURFACE LOW AND WARM FRONT JUST TO THE  
SOUTH OF THE AREA, SHOULD BRING ANOTHER ROUND OF SHOWERS AND  
SOME STORMS THIS AFTERNOON INTO EARLY THIS EVENING. AN ISOLATED  
STRONG STORM MAY OCCUR NEAR THE ILLINOIS BORDER, THOUGH THIS IS  
A SMALL (UNDER 20 PERCENT) CHANCE, AS IT SHOULD REMAIN CLOUDY  
ALL DAY AND LIMIT ANY POTENTIAL INSTABILITY FROM DEVELOPING.  
 
THE BETTER POTENTIAL FOR HEAVY RAIN AND FLOODING SHOULD MAINLY  
IN SOUTHERN PORTIONS OF THE AREA, WHERE THE FLOOD WATCH REMAINS  
IN EFFECT UNTIL 7 PM CDT THIS EVENING. IT WOULD NOT TAKE A LOT  
OF ADDITIONAL RAINFALL TO CAUSE SOME FLOODING ISSUES, ESPECIALLY  
IN URBAN AREAS, SO WILL CONTINUE TO MONITOR THIS POTENTIAL.  
 
THE BEACH HAZARDS STATEMENT FOR A HIGH SWIM RISK REMAINS IN  
EFFECT THROUGH EARLY TUESDAY EVENING FOR ALL BEACHES ALONG LAKE  
MICHIGAN FROM SHEBOYGAN TO KENOSHA COUNTIES. THE COMBINATION OF  
GUSTY ONSHORE WINDS AND HIGH WAVES WILL BRING THE HIGH SWIM RISK  
CONDITIONS. STAY OUT OF THE WATER AND AWAY FROM DANGEROUS AREAS  
LIKE PIERS AND BREAK WALLS. THIS MAY NEED TO BE EXTENDED INTO  
WEDNESDAY EVENING, IF THE HIGH WAVES PERSIST.  
 
WOOD  
 

 
   
SHORT TERM
 
 
ISSUED 1055 PM CDT FRI SEP 18 2026  
 
CURRENT OVERNIGHT THROUGH SUNDAY:  
 
SYNOPSIS/MESOANALYSIS: WEAK AREA OF SURFACE LOW PRESSURE CONTINUES  
TO MOVE INTO WEST-CENTRAL IOWA LATE THIS EVENING. ROOTED IN THE 850  
MB LAYER, WARM ADVECTION IS BLOSSOMING ALONG THE NORTHEAST PERIPHERY  
OF THE SURFACE LOW, COMBINING WITH AN EAST-WEST BAND OF  
FRONTOGENESIS & BISECTING LOW LEVEL JET TO SPARK WIDESPREAD  
SHOWERS AND STORMS FROM NEAR THE DELLS WESTWARD. THIS ACTIVITY  
WILL SLIDE EAST-SOUTHEAST INTO THE REGION AFTER MIDNIGHT,  
PERSISTING INTO THE FIRST HALF OF SATURDAY MORNING. THE  
SHOWERS/STORMS WILL BRING MODERATE TO TORRENTIAL DOWNPOURS,  
WITH FLASH FLOODING POSSIBLE IN LOCATIONS WHERE THE HEAVIEST  
RATES TRACK REPEATEDLY. ACTIVITY IS EXPECTED TO SLIDE SOUTHEAST  
OF THE AREA BY MID-DAY SATURDAY, WITH THE FORECAST PICTURE  
BECOMING MORE UNCERTAIN THEREAFTER. THE LOW CURRENTLY OVER IOWA  
WILL APPROACH OR PULL JUST SOUTH OF THE WISCONSIN-ILLINOIS  
BORDER THROUGH THE AFTERNOON & EARLY EVENING, WITH CONTINUED  
WARM ADVECTION ALONG ITS NORTHERN PERIPHERY POSING AT LEAST  
CONDITIONAL POTENTIAL FOR ADDITIONAL SHOWERS AND STORMS NEAR AND  
SOUTH OF I-94. STORM DEVELOPMENT AND COVERAGE WILL BE DEPENDENT  
ON THERMODYNAMIC RECOVERY IN THE WAKE OF MORNING PRECIP, IN  
ADDITION TO ANY EMBEDDED DISTURBANCES IN THE FLOW ALOFT. IN THE  
EVENT DEVELOPMENT OCCURS, ADDITIONAL HEAVY DOWNPOURS AND  
FLOODING IMPACTS WOULD BE POSSIBLE. GIVEN THE CONDITIONAL  
POTENTIAL FOR ADDITIONAL AFTERNOON STORM DEVELOPMENT, THE FLOOD  
WATCH HAS NOW BEEN EXTENDED UNTIL 7 PM SATURDAY EVENING OVER THE  
SOUTHERN HALF OF THE AREA. FURTHER NORTH, THE FLOOD WATCH  
REMAINS IN EFFECT UNTIL 1 PM SATURDAY. STAY VIGILANT FOR  
POSSIBLE FLOOD AND FLASH FLOOD WARNINGS THROUGH SATURDAY  
AFTERNOON, AND NEVER DRIVE THROUGH FLOODED ROADWAYS.  
 
REST OF OVERNIGHT INTO SATURDAY MORNING: EXPECTING WIDESPREAD  
SHOWERS AND STORMS ACROSS SOUTHERN WISCONSIN. STORMS WILL BRING  
VARYING RAINFALL RATES OF MODERATE TO TORRENTIAL INTENSITY, WITH  
WIDESPREAD PRECIP COVERAGE & LONG PRECIP DURATION POSING THE  
POTENTIAL FOR AT LEAST MINOR HYDROLOGIC IMPACTS (URBAN/SMALL STREAM  
FLOODING, PONDING OF WATER ON ROADS, AND MINOR RISES ON RIVERS)  
AREAWIDE. FLASH FLOODING WILL BE POSSIBLE IN LOCATIONS WHERE THE  
HEAVIER RATES TRACK REPEATEDLY. ENVIRONMENTALLY, THE MOST FAVORABLE  
CORRIDOR FOR FLASH FLOODING IMPACTS WILL ALIGN NEAR & WEST OF A  
KENOSHA-WATERTOWN-WISCONSIN DELLS LINE THROUGH EARLY SATURDAY  
MORNING. IT WILL BE IN THIS PART OF THE AREA THAT 1) SUFFICIENT  
MUCAPE & EMBEDDED CONVECTION WILL ALLOW FOR THE MATERIALIZATION OF  
HEAVY TO TORRENTIAL RAINFALL RATES AND 2) ELONGATED SOUTHEAST-  
NORTHWEST FRONTOGENESIS BANDS AND THEIR INTERSECTION WITH THE LOW  
LEVEL JET WILL PROVIDE FOCUS POINTS FOR TRAINING TO OCCUR.  
COLLECTIVELY, THE GOING FORECAST OF WIDESPREAD 1-3" RAINFALL  
ACCUMULATIONS WITH LOCALLY HIGHER TOTALS IN THE 3-6"+ RANGE REMAINS  
ON TRACK, WITH THE CORRIDORS OF HIGHER TOTALS MOST LIKELY ALONG/WEST  
OF THE KENOSHA-WATERTOWN-WISCONSIN DELLS LINE. FLOOD WATCH THUS  
REMAINS IN EFFECT INTO SATURDAY MORNING.  
 
SATURDAY AFTERNOON & EVENING: A MORE CONDITIONAL WINDOW OF  
ADDITIONAL STORM DEVELOPMENT WILL BE IN PLACE PREDOMINANTLY ALONG  
AND SOUTH OF I-94 AS LOW PRESSURE MOVES NEAR OR JUST SOUTH OF THE  
WISCONSIN-ILLINOIS BORDER. SUFFICIENT RECOVERY POST-AM PRECIP WILL  
BE ESSENTIAL FOR THIS DEVELOPMENT TO OCCUR, WITH AN ADDITIONAL  
TRIGGER FROM ANY PASSING DISTURBANCES ALOFT LIKELY BEING NEEDED AS  
WELL. WATER VAPOR IMAGERY SHOWS ONE SUCH DISTURBANCE NEARING THE  
NEBRASKA SANDHILLS AT THE CURRENT HOUR, WITH CRUDE EXTRAPOLATIONS  
BRINGING IT ACROSS SOUTHERN WISCONSIN FROM ~11 AM - 7 PM SATURDAY IF  
IT MANAGES TO HOLD TOGETHER. SUSPECT THAT IT'S THIS FEATURE THAT  
MORE ACTIVE 00Z CAM SOLUTIONS ARE LATCHING ONTO GIVEN ITS ESTIMATED  
ARRIVAL TIME & THE TIMING OF THEIR SIMULATED STORM RE-DEVELOPMENT.  
WILL THUS BE MONITORING TRENDS VERY CLOSELY THROUGH TOMORROW  
MORNING, AS LITTLE ADDITIONAL RAINFALL WOULD BE REQUIRED TO CREATE  
ADDITIONAL FLOODING PROBLEMS. HAVE THUS EXTENDED THE FLOOD WATCH  
THROUGH 7 PM SATURDAY ACROSS THE SOUTHERN HALF OF THE AREA. SEVERE  
WEATHER POTENTIAL WOULD BE LOW IN ANY RE-DEVELOPMENT, THOUGH AN  
ISOLATED STORM WITH GUSTY WINDS WOULDN'T BE ENTIRELY OUT OF THE  
REALM OF POSSIBILITY NEAR THE WISCONSIN-ILLINOIS BORDER.  
 
QUIGLEY  
 

 
   
LONG TERM
 
 
ISSUED 1055 PM CDT FRI SEP 18 2026  
 
SUNDAY NIGHT THROUGH FRIDAY:  
 
STRONG HIGH PRESSURE CENTERED JUST NORTH OF THE GREAT LAKES WILL  
VERY GRADUALLY SHIFT EASTWARD SUNDAY NIGHT THROUGH WEDNESDAY. A  
COOLER AND MUCH DRIER AIRMASS IS EXPECTED ACROSS SOUTHERN WISCONSIN  
THROUGH THIS PERIOD UNDER THE INFLUENCE OF THE HIGH AND AN UPPER  
LEVEL TROUGHING PATTERN. BELOW NORMAL HIGH AND LOW TEMPS ARE  
ANTICIPATED THROUGH MID-WEEK.  
 
LATEST FORECAST MODELS SUGGEST THE UPPER LEVEL TROUGH AND SURFACE  
HIGH WILL MAINTAIN ENOUGH OF AN INFLUENCE ACROSS SOUTHERN WISCONSIN  
FOR CONTINUED MAINLY DRY WEATHER LATE WEEK NEXT WEEK, WITH  
TEMPERATURES GRADUALLY RETURNING TO NEAR NORMAL BY THE END OF THE  
WEEK AS UPPER LEVEL RIDGING BEGINS TO BUILD IN FROM THE WEST.  
 
DDV  
 

 
   
AVIATION
 
 
ISSUED 558 AM CDT SAT SEP 19 2026  
 
THE FIRST ROUND OF HEAVY RAINFALL AS PUSHED SOUTH OF THE AREA,  
WITH LINGERING MODERATE RAIN OVER MOST OF THE AREA. THIS  
ACTIVITY SHOULD LINGER INTO MIDDLE MORNING, BEFORE A POSSIBLE  
LULL IN THE ACTIVITY BY LATER THIS MORNING OCCURS. CEILINGS  
BELOW 1000 FEET AGL AND VISIBILITY OF 1 TO 4 MILES ARE GENERALLY  
EXPECTED THIS MORNING, WITH GUSTY SOUTHEAST WINDS GRADUALLY  
WEAKENING.  
 
THERE ARE ADDITIONAL SHOWERS AND STORMS WITH HEAVY RAINFALL  
REMAINING TO THE WEST AND SOUTHWEST OF THE AREA EARLY THIS  
MORNING. THIS ACTIVITY SHOULD MAINLY MISS OR JUST CLIP AREAS  
SOUTHWEST OF MADISON.  
 
ANOTHER ROUND OF SHOWERS AND SOME STORMS SHOULD OCCUR THIS  
AFTERNOON INTO EARLY THIS EVENING ACROSS THE AREA. THE BETTER  
POTENTIAL FOR HEAVY RAIN SHOULD BE FOR MADISON AND MILWAUKEE AND  
SOUTH. LIGHTER SOUTHEAST TO EAST WINDS ARE EXPECTED THIS  
AFTERNOON, AS LOW PRESSURE PASSES BY TO THE SOUTH. CEILINGS  
SHOULD REMAIN BELOW 1000 FEET AGL THIS AFTERNOON AND EARLY  
EVENING, WITH 1 TO 4 MILE VISIBILITY WITHIN THE SHOWERS AND  
STORMS.  
 
SHOWERS AND A FEW STORMS SHOULD LINGER INTO THE EVENING,  
GRADUALLY PUSHING SOUTHEAST OF THE AREA LATER TONIGHT INTO EARLY  
SUNDAY MORNING. WINDS WILL BECOME EAST TO NORTHEAST AND INCREASE  
BY SUNDAY MORNING. CEILINGS SHOULD REMAIN BELOW 1000 FEET AGL  
INTO EARLY SUNDAY MORNING, BEFORE RISING TO ABOVE 3000 FEET AGL  
BY SUNDAY AFTERNOON. VISIBILITY SHOULD BE IN THE 1 TO 4 MILE  
RANGE UNTIL THE RAIN MOVES OUT OF THE AREA.  
 
WOOD  
 

 
   
MARINE
 
 
ISSUED 558 AM CDT SAT SEP 19 2026  
 
LOW PRESSURE AROUND 29.8 INCHES WILL MOVE EAST NORTHEAST TOWARD  
FAR SOUTHERN LAKE MICHIGAN TODAY, THEN JUST SOUTH OF THE  
SOUTHERN PORTIONS OF THE LAKE TONIGHT. WINDS WILL BECOME  
SOUTHEAST AND GUSTY AHEAD OF THE LOW, THEN SHIFT NORTHEAST  
TONIGHT AS THE LOW PASSES TO THE SOUTH. AREAS OF WIDESPREAD  
SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE PASSING AREA OF LOW  
PRESSURE TODAY INTO TONIGHT.  
 
GUSTY EAST TO NORTHEAST WINDS ARE THEN EXPECTED SUNDAY THROUGH  
MONDAY NIGHT, AS LOW PRESSURE SLOWLY MOVES INTO THE OHIO RIVER  
VALLEY. HIGH PRESSURE AROUND 30.5 INCHES WILL MOVE SOUTHEAST  
INTO ONTARIO DURING THIS PERIOD. GUSTS COULD OCCASIONALLY  
APPROACH GALE FORCE SUNDAY INTO MONDAY NIGHT, MAINLY OVER  
SOUTHERN PORTIONS OF THE LAKE. WINDS WILL STEADILY TAPER TUESDAY  
THROUGH WEDNESDAY, AS THE HIGH PRESSURE SYSTEM MOVES INTO  
QUEBEC AND NEW ENGLAND.  
 
A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH EARLY TUESDAY  
EVENING FOR THE NEARSHORE WATERS OF LAKE MICHIGAN, FOR THE  
COMBINATION OF GUSTY ONSHORE WINDS AND BUILDING WAVES THROUGH  
THIS PERIOD. THIS MAY NEED TO BE EXTENDED INTO WEDNESDAY  
EVENING, IF THE HIGH WAVES PERSIST.  
 
WOOD  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060-WIZ066-WIZ071-WIZ072  
UNTIL 7 PM TUESDAY.  
 
FLOOD WATCH...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056-WIZ057-WIZ058-  
WIZ059-WIZ060 UNTIL 1 PM SATURDAY.  
 
FLOOD WATCH...WIZ062-WIZ063-WIZ064-WIZ065-WIZ066-WIZ067-WIZ068-  
WIZ069-WIZ070-WIZ071-WIZ072 UNTIL 7 PM SATURDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646 UNTIL 7 PM  
TUESDAY.  
 

 
 

 
 
VISIT US AT WEATHER.GOV/MILWAUKEE  
 
FOLLOW US ON FACEBOOK, X, AND YOUTUBE AT:  
WWW.FACEBOOK.COM/NWSMILWAUKEE  
WWW.X.COM/NWSMILWAUKEE  
WWW.YOUTUBE.COM/NWSMILWAUKEE  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab WI Page Main Text Page