180  
FXUS63 KMKX 210500  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
1200 AM CDT MON SEP 21 2026  
   
KEY MESSAGES  
 
- A PROLONGED PERIOD OF HIGH SWIM RISK CONDITIONS CONTINUES  
THROUGH THE START OF THE WEEK FOR ALL SOUTHERN WI BEACHES.  
 
- MOSTLY DRY WEATHER AND BELOW NORMAL TEMPS FOR THE FIRST HALF  
OF THE WEEK WITH GRADUALLY WARMING TEMPS INTO THE WEEKEND.  
 
 
   
SHORT TERM  
 
ISSUED 1200 AM CDT MON SEP 21 2026  
 
TODAY THROUGH TUESDAY:  
 
HIGH PRESSURE MEANDERING OVER/JUST NORTH OF THE GREAT LAKES  
REGION AND PERSISTENT EAST TO NORTHEASTERLY FLOW WILL CONTINUE  
TO DOMINATE THE WEATHER PATTERN ACROSS SOUTHERN WI FOR THE  
START OF THE WEEK. THIS SHOULD KEEP TEMPS FAIRLY SEASONAL WITH  
DAILY HIGHS IN THE 60S, WHILE NIGHTLY LOWS DIP INTO THE UPPER  
40S AND LOW 50S. ANY CLOUD COVER COULD KEEP THE OVERNIGHT TEMPS  
A FEW DEGREES WARMER THAN THE CURRENT FORECAST, BUT NONETHELESS  
WILL SEE FALL-LIKE LOWS TO START THE WEEK.  
 
AS FOR PRECIP CHANCES, THE +1030MB HIGH CENTERED TO THE  
NORTHEAST LOOKS TO BRING PLENTY OF DRY AIR AND SUBSIDENCE TO THE  
AREA. HOWEVER, CONTINUE TO SEE A SIGNAL ON THE 00Z MODELS OF  
500MB SHORTWAVE TROUGH TRAVERSING THE DAKOTAS TODAY AND MAKING  
ITS WAY INTO THE MIDWEST ON TUESDAY. WHILE THESE TWO FEATURES  
WILL COMPETE WITH EACH OTHER, CANNOT COMPLETELY RULE OUT SEEING  
THE SHORTWAVE TROUGH PAIR WITH PWATS AROUND 1 INCH AND  
ADDITIONAL MOISTURE OFF OF LAKE MICHIGAN TO BE ENOUGH TO SPUR  
SPORADIC SPRINKLES/DRIZZLE LATER TODAY INTO TUESDAY MORNING  
ACROSS SOUTHERN PORTIONS OF THE CWA, ESPECIALLY TOWARD THE WI/IL  
BORDER WHERE CLOUD COVER IS MOST LIKELY. OVERALL IF THIS  
SCENARIO PANS OUT, ANY ACTIVITY MAY NOT BE MEASURABLE (>0.01  
INCH), BUT COULD STILL BRING A PERIOD OF DAMP, MISTY, AND DREARY  
CONDITIONS INTO THE FIRST HALF OF TUESDAY. ONCE THE SHORTWAVE  
TROUGH TREKS EAST, THEN THE HIGH PRESSURE DOMINANCE TAKES A  
FIRMER HOLD OVER THE AREA.  
 
LASTLY WITH THE PERSISTING BREEZY ONSHORE FLOW OVER THE PAST  
AND UPCOMING DAYS, WAVES UP TO 4-9 FT ARE EXPECTED TO CONTINUE  
THROUGH TUESDAY. THUS RESULTING IN HIGH SWIM RISK CONDITIONS  
FOR ALL SOUTHERN WI BEACHES OVER THE NEXT FEW DAYS.  
 
WAGNER  
 
 
   
LONG TERM  
 
ISSUED 1200 AM CDT MON SEP 21 2026  
 
WEDNESDAY THROUGH SUNDAY:  
 
THE STRONGER HIGH PRESSURE CONTINUES TO INFLUENCE THE PATTERN  
THROUGH MIDWEEK, BUT WILL GRADUALLY SHIFT EAST AND WINDS ARE  
PROGGED TO LESSEN. WHILE HIGH SWIM RISK CONDITIONS LINGER INTO  
WEDNESDAY, THESE CONDITIONS SHOULD BEGIN TO EASE INTO THURSDAY.  
OTHERWISE, UPPER-LEVEL RIDGE IS PROGGED TO BUILD INTO THE UPPER  
MIDWEST THROUGH THE SECOND HALF OF THE WEEK. EXPECT MOSTLY DRY  
CONDITIONS AND GRADUALLY WARMING HIGH TEMPS EACH DAY INTO THE  
WEEKEND.  
 
WAGNER  
 
 
   
AVIATION  
 
ISSUED 1200 AM CDT MON SEP 21 2026  
 
EXPECT CEILING CONDITIONS BOUNCING BETWEEN VFR/MVFR LEVELS  
TONIGHT WITH BREEZY NORTHEASTERLY WINDS. EVENTUALLY EXPECTING  
GUSTS ALONG THE LAKESHORE TO EASE, BUT STILL LOOKING BREEZY  
THROUGH DAY THE MORNING. OTHERWISE, BREEZY EASTERLY WINDS LOOK  
TO PICK UP AGAIN THROUGH THE LATE MORNING AND PERSIST THROUGH  
THE AFTERNOON. SOME LOWER CEILINGS MAY LINGER ALONG THE WI/IL  
BORDER THIS MORNING, BUT CEILINGS ARE EXPECTED TO LIFT FROM  
NORTH TO SOUTH AS HIGH PRESSURE BUILDS DOWN INTO THE GREAT  
LAKES REGION FOR THE START OF THE WEEK.  
 
WAGNER  
 
 
   
MARINE  
 
ISSUED 1200 AM CDT MON SEP 21 2026  
 
BUILDING HIGH PRESSURE MEANDERING OVER/JUST NORTH OF THE GREAT  
LAKES WILL KEEPING BREEZY NORTHEAST TO EASTERLY FLOW THROUGH  
MIDWEEK. THUS RESULTING IN ELEVATED WAVE HEIGHTS AND SMALL CRAFT  
CONDITIONS THROUGH AT LEAST WEDNESDAY. GIVEN THE TIGHTER  
PRESSURE GRADIENT ALSO COULD NOT RULE OUT SPORADIC, BRIEF GALE  
FORCE GUSTS ACROSS CENTRAL AND SOUTHERN PORTIONS OF LAKE  
MICHIGAN THROUGH TODAY. OTHERWISE, WINDS GRADUALLY DIMINISH FOR  
THE SECOND HALF OF THE WEEK AS THE HIGH PRESSURE WEAKENS AND  
PUSHES FURTHER EAST.  
 
WAGNER  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060-WIZ066-WIZ071-WIZ072  
UNTIL 7 PM WEDNESDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646 UNTIL 7 PM  
WEDNESDAY.  
 
 
 
 
 
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