249  
FXUS63 KMKX 162346 AAA  
AFDMKX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
646 PM CDT SUN AUG 16 2026  
   
KEY MESSAGES  
 
- AREAS OF FOG TONIGHT, PARTICULARLY OVER THE WESTERN HALF OF  
THE AREA.  
 
- SHOWERS AND THUNDERSTORMS RETURN TO THE FORECAST TUESDAY EVENING.  
 
- DRY AND PLEASANT CONDITIONS WEDNESDAY THROUGH THURSDAY. RAIN  
CHANCES RETURN FRIDAY.  
 
 
   
UPDATE  
 
ISSUED 645 PM CDT SUN AUG 16 2026  
 
THE DIURNAL CUMULUS CLOUDS WILL DIMINISH IN COVERAGE, BUT NOT  
CONFIDENT IN A CLEAR NIGHT FOR AREAS IN EAST CENTRAL AND  
SOUTHEAST WI. DRIER AIR AND ALSO A WIND SHIFT TO THE NNE RIGHT  
ALONG THE LAKESHORE COULD HELP KEEP A FEW LOWER CLOUDS AROUND  
TONIGHT. LOWS WILL BE AROUND 60. FOG IS POSSIBLE WEST OF  
MADISON, ESPECIALLY WITHIN THE WISCONSIN RIVER VALLEY.  
 
CRONCE  
 
 
   
SHORT TERM  
 
ISSUED 110 PM CDT SUN AUG 16 2026  
 
THIS AFTERNOON THROUGH MONDAY NIGHT:  
 
SYNOPSIS/MESOANALYSIS: SURFACE OBSERVATIONS SHOW A COLD FRONT  
WORKING INTO SOUTHERN WISCONSIN EARLY THIS AFTERNOON. WHILE MULTIPLE  
WIND SHIFTS ARE APPARENT REGIONALLY, THE "TRUE" FRONTAL BOUNDARY  
EXTENDS FROM THE FOND DU LAC AREA SOUTHWEST THROUGH MADISON, AND IS  
MARKED BY ABRUPT DEW POINT DROPS INTO THE MID-60S IN THE WAKE OF ITS  
PASSAGE. WITH A STILL HUMID & MODESTLY UNSTABLE AIR MASS IN PLACE  
AHEAD OF THE FRONT, SCATTERED THUNDERSHOWERS REMAIN POSSIBLE IN  
SOUTHEAST WISCONSIN PRIOR TO THE FRONT'S MID-AFTERNOON DEPARTURE.  
APART FROM A FEW LIGHTNING FLASHES, HAZARDS AREN'T EXPECTED IN ANY  
ACTIVITY. CURRENTLY OVER THE DAKOTAS, HIGH PRESSURE WILL BUILD INTO  
THE UPPER MISSISSIPPI VALLEY TONIGHT, RESULTING IN CLEARING SKIES  
AND WEAKENING WINDS. SOME FOG COULD DEVELOP AS THESE CONDITIONS  
BECOME ESTABLISHED AFTER MIDNIGHT, WITH POTENTIAL BEING HIGHEST  
ACROSS THE WESTERN HALF OF THE AREA. THE HIGH WILL CROSS THE STATE  
ON MONDAY, BRINGING SEASONABLE AND PLEASANT CONDITIONS. THE HIGH  
WILL SHIFT EAST MONDAY NIGHT AS A NEW AREA OF LOW PRESSURE BUILDS  
INTO THE NORTHERN PLAINS, ALLOWING WINDS TO TURN SOUTHWESTERLY  
REGIONALLY. THE WIND SHIFT WILL GRADUALLY BRING MORE HUMID AIR BACK  
INTO SOUTHERN WISCONSIN, WITH AN ISOLATED THUNDERSTORM POSSIBLE  
CLOSER TO DAYBREAK TUESDAY.  
 
THIS AFTERNOON: WILL BE MONITORING THE PROGRESS OF THE COLD FRONT &  
ANY THUNDERSHOWER DEVELOPMENT ALONG IT THROUGH 4 PM. HIGHEST NEAR-  
TERM THUNDERSHOWER POTENTIAL WILL RESIDE WITHIN A BAND OF AGITATED  
CUMULUS CLOUDS & RADAR RETURNS MOVING EAST FROM THE MADISON AREA,  
THOUGH ADDITIONAL DEVELOPMENT WILL BE POSSIBLE AS THE FRONT IMPINGES  
UPON A STILL MUGGY AIR MASS IN SOUTHEAST WISCONSIN. SHOWER DEPTHS  
HAVE REMAINED LARGELY BELOW THE -10C LEVEL OVER THE LAST HOUR, WHICH  
HAS RESULTED IN NO LIGHTNING IN ANY ACTIVITY DEVELOPING THUS FAR.  
NEVERTHELESS, A FEW TALLER SHOWERS CAPABLE OF A COUPLE LIGHTNING  
FLASHES CAN'T BE ENTIRELY RULED OUT GIVEN THE INSTABILITY STILL  
AVAILABLE OVER SOUTHEAST WISCONSIN. MOVE INDOORS IF ANY THUNDER  
APPROACHES YOUR LOCATION.  
 
QUIGLEY  
 
 
   
LONG TERM  
 
ISSUED 110 PM CDT SUN AUG 16 2026  
 
TUESDAY THROUGH SUNDAY:  
 
SYNOPSIS: MOISTURE WILL CONTINUE TO WORK BACK INTO SOUTHERN  
WISCONSIN TUESDAY, LEADING TO MUGGIER CONDITIONS. A COLD FRONT WILL  
SWING THROUGH THE WESTERN GREAT LAKES TUESDAY EVENING INTO  
WEDNESDAY, TRIGGERING THE NEXT ROUND OF SHOWER AND THUNDERSTORM  
DEVELOPMENT. TUESDAY EVENING & NIGHT CONTINUES TO BE MOST FAVORED  
FOR STORMS IN SOUTHERN WISCONSIN. BROADER INGREDIENTS WILL BE IN  
PLACE FOR A FEW STRONGER STORMS WITH HEAVY DOWNPOURS, THOUGH TRENDS  
CONTINUE TO BE MONITORED FOR MORE PRECISE PLACEMENT & INTENSITY  
DETAILS. THE COLD FRONT IS FORECAST TO BE SOUTH OF THE WISCONSIN-  
ILLINOIS BORDER BY WEDNESDAY MORNING, WITH DRIER NORTHERLY FLOW &  
PASSING HIGH PRESSURE LEADING TO PLEASANT & PRECIP-FREE CONDITIONS  
WEDNESDAY AFTERNOON THROUGH THURSDAY. WINDS WILL TREND SOUTHWESTERLY  
ON FRIDAY, BRINGING MILDER AND MODESTLY MORE HUMID AIR TO THE  
REGION. THE NEXT COLD FRONT IS FORECAST TO MOVE THROUGH THE WESTERN  
GREAT LAKES FRIDAY EVENING, WHEN SOME SCATTERED SHOWERS AND  
THUNDERSTORMS WILL BE POSSIBLE. PLEASANT CONDITIONS WILL RETURN BY  
THE SATURDAY-SUNDAY TIME FRAME BEHIND THE DEPARTED FRONT.  
 
TUESDAY EVENING: CONTINUE TO ANTICIPATE A WINDOW FOR SCATTERED  
SHOWERS AND STORMS BETWEEN ~3 PM & MIDNIGHT ALONG THE APPROACHING  
COLD FRONT. BROAD SETUP DETAILS---PARTICULARLY FORCING FROM THE  
FRONT, RELATIVELY FAVORABLE ARRIVAL TIMING OF THE FRONTAL FORCING,  
AND SUFFICIENT WIND SHEAR---POINT TOWARD AN ENVIRONMENT GENERALLY  
FAVORABLE FOR MORE ORGANIZED STORM DEVELOPMENT IN SOUTHERN  
WISCONSIN. THE LIMITING FACTOR, HOWEVER, REMAINS THE QUALITY OF  
MOISTURE RETURN (& THUS INSTABILITY) AHEAD OF THE ENCROACHING  
FRONT/ON THE BACK SIDE OF DEPARTING HIGH PRESSURE. WITH A SOURCE  
REGION CENTERED WELL TO THE WEST OVER SOUTH DAKOTA/NEBRASKA,  
RETURNING MOISTURE WILL BE RACING THE COLD FRONT TO SOUTHERN  
WISCONSIN, WITH ANY COMBINATION OF A FASTER FRONTAL SPEED AND/OR  
SLOWER-DEPARTING HIGH IMPEDING ITS PROGRESS. THIS WILL BE THE MAIN  
TREND BEING MONITORED OVER THE NEXT 24-36 HOURS. A STRONGER STORM  
WITH GUSTY WINDS WOULD BE POSSIBLE WHEREVER THE DEEPEST (65+ DEGF)  
MOISTURE RETURNS CAN ESTABLISH, WITH CURRENT GUIDANCE SUGGESTING THE  
GREATEST POTENTIAL FROM MADISON & POINTS SOUTHWEST. SEASONABLY MOIST  
CONDITIONS WILL SUPPORT HEAVY DOWNPOURS IN ANY STORMS, THOUGH  
FLOODING POTENTIAL WOULD BE LOW IN THE ABSENCE OF ANY TRAINING.  
 
QUIGLEY  
 
 
   
AVIATION  
 
ISSUED 645 PM CDT SUN AUG 16 2026  
 
THE BREEZIER NORTHWEST WINDS WILL DIMINISH QUICKLY WITH SUNSET.  
LESS CONFIDENCE ON CLEAR SKIES FOR AREAS IN EAST CENTRAL AND  
SOUTHEAST WI TONIGHT AS A PUSH OF DRIER AND SLIGHTLY COOLER AIR  
OVERSPREADS THE AREA. ANY FEW-SCT COVERAGE WOULD BE VFR WITH  
BASES AROUND 4000 FT AGL. THERE SHOULD ALSO BE A WIND SHIFT TO  
NNE ALONG THE LAKESHORE OVERNIGHT. THE LAKE BREEZE WILL HELP  
KEEP THE WINDS OUT OF THE NE FOR MUCH OF THE DAY WHILE INLAND  
AREAS WILL HAVE GENERALLY NW WINDS. WINDS WILL BE LIGHTER MONDAY  
DUE TO HIGH PRESSURE OVERHEAD.  
 
CRONCE  
 
 
   
MARINE  
 
ISSUED 110 PM CDT SUN AUG 16 2026  
 
A COLD FRONT IS APPROACHING THE OPEN WATERS OF LAKE MICHIGAN THIS  
AFTERNOON, RESULTING IN BREEZY WEST-NORTHWEST WINDS. THESE  
CONDITIONS WILL CONTINUE INTO THIS EVENING AS THE FRONT CLEARS EAST  
OF THE WATERS. A SCATTERED SHOWER OR THUNDERSTORM IS POSSIBLE ALONG  
THE DEPARTING BOUNDARY, PARTICULARLY OVER THE SOUTHERN THIRD OF THE  
WATERS. SEVERE WEATHER IS NOT ANTICIPATED.  
 
A NEW AREA OF 1018 MB HIGH PRESSURE WILL BUILD IN FROM THE NORTHERN  
GREAT PLAINS LATE TONIGHT INTO MONDAY, BRINGING LIGHT AND VARIABLE  
WINDS TO THE WATERS THROUGH THE MAJORITY OF MONDAY AND MONDAY NIGHT.  
A SLOW-MOVING COLD FRONT WILL APPROACH FROM THE NORTHERN GREAT  
PLAINS TUESDAY INTO WEDNESDAY, BRINGING INCREASING SOUTHWEST WINDS  
AND CHANCES FOR THUNDERSTORMS. TUESDAY EVENING AND NIGHT APPEARS  
MOST FAVORED FOR STORM POTENTIAL, WITH STORM CHANCES EXPECTED TO  
MOVE WELL SOUTH OF THE WATERS ON WEDNESDAY. 1016 MB HIGH PRESSURE  
WILL MOVE THROUGH THE WESTERN GREAT LAKES WEDNESDAY THROUGH  
THURSDAY, WITH LIGHT AND VARIABLE WINDS PREVAILING ACROSS THE  
WATERS. THE NEXT THUNDERSTORM CHANCES ARRIVE FRIDAY AFTERNOON AND  
EVENING, WHEN THE NEXT COLD FRONT IS EXPECTED TO MOVE ACROSS LAKE  
MICHIGAN.  
 
SMALL CRAFT ADVISORY CONDITIONS ARE NOT ANTICIPATED THROUGH THIS  
WEEK IN NEARSHORE ZONES. SCATTERED SHOWERS AND THUNDERSTORMS ARE  
POSSIBLE ALONG A PASSING COLD FRONT THIS AFTERNOON. ADDITIONAL  
SHOWER AND THUNDERSTORM CHANCES ARE FORECAST TUESDAY EVENING/NIGHT,  
AS WELL AS ON FRIDAY AFTERNOON & EVENING.  
 
QUIGLEY  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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