157  
FXUS63 KMKX 210609  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
109 AM CDT TUE JUL 21 2026  
   
KEY MESSAGES  
 
- DRIER & LESS HUMID THROUGH THE END OF THE WORK WEEK. MUGGY  
CONDITIONS RETURN LATE WEEKEND.  
 
- SHOWERS & STORMS RETURN TO THE FORECAST SATURDAY INTO SUNDAY.  
 
 
   
SHORT TERM  
 
ISSUED 100 AM CDT TUE JUL 21 2026  
 
TODAY THROUGH WEDNESDAY:  
 
A COLD FRONT WILL CONTINUE SOUTHWARD ACROSS THE REGION PREDAWN  
THIS MORNING, WITH GUSTY NW WINDS ARRIVING BEHIND IT POST-DAWN.  
20-30 MPH GUSTS ARE EXPECTED AT TIMES THROUGH THE DAYTIME HOURS.  
HIGHS IN THE LOW 80S EXPECTED. THE LATEST CAMS SUGGEST THAT A  
SPRINKLE OF RAIN CANNOT BE COMPLETELY RULED OUT FROM SOME OPEN-  
CELLULAR SHOWERS BENEATH THE STRONG SUBSIDENCE INVERSION, WE CAN  
LIMIT THE ODDS OF ANY MEASURABLE PRECIP TO 15% OR LESS.  
 
EVEN COOLER AND MORE PLEASANT CONDITIONS FORECAST FOR WEDNESDAY,  
HIGHS IN THE 70S AND DEWPOINTS AROUND 50 (NOTICEABLY DRIER  
AIR). HIGH PRESSURE PASSES DIRECTLY OVERHEAD, WITH MOSTLY SUNNY  
SKIES AND DRY WEATHER.  
 
SHEPPARD  
 
 
   
LONG TERM  
 
ISSUED 100 AM CDT TUE JUL 21 2026  
 
WEDNESDAY NIGHT THROUGH SUNDAY:  
 
SYNOPSIS: HIGH PRESSURE WILL LINGER OVER THE WESTERN GREAT LAKES  
THROUGH THURSDAY, MAINTAINING A COOLER AND DRY WEATHER PATTERN. THE  
HIGH WILL SHIFT EAST FRIDAY INTO SATURDAY, ALLOWING FOR SOUTHERLY  
WINDS AND STEADILY CLIMBING SURFACE TEMPERATURES THROUGH THE  
WEEKEND. INCREASING HUMIDITY WILL EVENTUALLY ACCOMPANY THE RISING  
TEMPERATURES, THOUGH ITS ARRIVAL WILL LAG BEHIND THAT OF THE WARMER  
AIR TEMPERATURES. MORE HUMID CONDITIONS WILL THUS HOLD OFF UNTIL  
SATURDAY NIGHT INTO SUNDAY. WITH WARMER TEMPERATURES & HUMIDITY  
ATTEMPTING TO WORK BACK INTO THE AREA, SHOWER AND THUNDERSTORM  
CHANCES RETURN TO THE FORECAST SATURDAY NIGHT INTO SUNDAY.  
 
SATURDAY THROUGH SUNDAY: THE NEXT PERIOD OF POTENTIAL WEATHER  
IMPACTS ARRIVES FOLLOWING A QUIET END TO THE WORK WEEK. IMPACTS  
COULD COME FROM A COMBINATION OF INCREASING HUMIDITY & HEAT INDICES  
ON SUNDAY, IN ADDITION TO CHANCES FOR SHOWERS AND THUNDERSTORMS  
SATURDAY NIGHT INTO SUNDAY. FINER DETAILS---NAMELY IF HEAT INDICES  
WILL APPROACH HEADLINE THRESHOLDS AND/OR IF ANY STORMS COULD BE  
STRONG/SEVERE---WILL BE REFINED AS TRENDS CLARIFY THROUGH THE END OF  
THIS WEEK, THOUGH INITIAL INDICATIONS ARE THAT CLOUDS & LIMITED AIR  
MASS RESIDENCE TIME WILL KEEP TEMPS & HEAT INDICES BELOW HEADLINE  
LEVELS. ANY STRONGER STORM POTENTIAL WILL DEPEND ON TIMING, THE  
DETAILS OF WHICH REMAIN MURKY THIS FAR OUT. WILL PROVIDE MORE  
UPDATES AS THIS PORTION OF THE PERIOD DRAWS CLOSER.  
 
QUIGLEY  
 
 
   
AVIATION  
 
ISSUED 100 AM CDT TUE JUL 21 2026  
 
A WEST BREEZE CONTINUES ACROSS THE REGION PREDAWN THIS MORNING,  
WITH GUSTY NORTHWEST WINDS ARRIVING BEHIND A COLD FRONT SHORTLY  
AFTER SUNRISE. ROUGHLY 20-25KT WIND GUSTS EXPECTED THROUGH THE  
DAYTIME HOURS, TAPERING DOWN INTO TONIGHT.  
 
PREDOMINANTLY DRY AND VFR CONDITIONS EXPECTED THROUGH THE TAF  
PERIOD. SOME LINGERING INSTABILITY OVER FAR SOUTHERN WI COULD  
YIELD A STRAY SHOWER OR PERHAPS EVEN A THUNDERSTORM OVER THE  
NEXT FEW HOURS.  
 
DIURNAL CUMULUS CLOUDS BETWEEN 3,500 AND 6,000 FT GRADUALLY  
BUILD INTO THE REGION FROM THE NORTHWEST LATER THIS MORNING, AND  
WE COULD EVEN SEE A TRACE (SPRINKLE) OF RAIN FROM THEM THIS  
AFTERNOON. CHANCES FOR MEASURABLE RAINFALL ARE 15% OR LESS FOR  
NOW, SO HAVE EXCLUDED THIS ACTIVITY FROM THE TAF FOR NOW. A  
PROB30 GROUP FOR 6SM SHRA MAY SUFFICE IN A FUTURE ISSUANCE.  
 
SHEPPARD  
 
 
   
MARINE  
 
ISSUED 100 AM CDT TUE JUL 21 2026  
 
LOW PRESSURE AROUND 29.3 INCHES WILL TRACK EASTWARD ACROSS JAMES  
BAY THROUGH TODAY, WITH HIGH PRESSURE OF 30.1 INCHES RESTING  
OVER CENTRAL SASKATCHEWAN AND MANITOBA. WINDS WILL VEER FROM  
SOUTHWEST TO NORTHWEST THROUGH THIS MORNING AND REMAIN BREEZY AS  
A COLD FRONT CROSSES LAKE MICHIGAN. GUSTY NORTH WINDS THEN  
ARRIVE LATE THIS AFTERNOON INTO TONIGHT, WITH A FEW GUSTS TO  
GALE FORCE POSSIBLE. WINDS ARE EXPECTED TO GRADUALLY WEAKEN BY  
THURSDAY, AS HIGH PRESSURE AROUND 30.2 INCHES BUILDS INTO THE  
GREAT LAKES REGION.  
 
SHEPPARD  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060 UNTIL 7 AM TUESDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644 UNTIL 7 AM WEDNESDAY.  
 
SMALL CRAFT ADVISORY...LMZ645-LMZ646 UNTIL 4 PM WEDNESDAY.  
 
 
 
 
 
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