342  
FXUS63 KMKX 201004  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
504 AM CDT SAT JUN 20 2026  
   
KEY MESSAGES
 
 
- WARM BUT SLIGHTLY BELOW NORMAL TEMPS EXPECTED THIS WEEKEND  
THROUGH EARLY NEXT WEEK.  
 
- CHANCE OF SHOWERS FOR SOUTHERN WI SUNDAY, BUT TRENDING FARTHER  
SOUTH TOWARD THE WI/IL BORDER THAN PREVIOUS FORECAST.  
 
- CHANCES FOR SHOWERS AND THUNDERSTORMS AT TIMES TOWARD THE  
MIDDLE OF THE WEEK.  
 

 
   
UPDATE
 
 
ISSUED 500 AM CDT SAT JUN 20 2026  
 
NO CHANGES TO THE GOING FORECAST.  
 
SHEPPARD  
 

 
   
SHORT TERM
 
 
ISSUED 1220 AM CDT SAT JUN 20 2026  
 
TODAY THROUGH SUNDAY NIGHT:  
 
BEHIND TONIGHT'S SHORTWAVE TROUGH PASSAGE, EXPECT MORE WESTERLY  
WINDS AND DRIER AIRMASS TO SETTLE ACROSS SOUTHERN WI THROUGH  
THE DAY AS WEAK HIGH PRESSURE TRACKS ACROSS THE AREA. LOOKING AT  
DAYTIME TEMPS IN THE LOW TO MID 70S UNDER MOSTLY SUNNY SKIES  
WITH OVERNIGHT INTO EARLY SUNDAY MORNING LOWS DIP BACK INTO THE  
MID TO LOWER 50S AS UPPER-LEVEL NORTHWESTERLY FLOW SETS UP  
ACROSS THE UPPER MIDWEST.  
 
CLOUDS THEN LOOK TO SNEAK BACK INTO THE REGION FOR SUNDAY AS A  
SWATH OF UNORGANIZED MID-LEVEL VORTICITY IS PROGGED TO TRACK  
ACROSS THE CORN BELT REGION. ACCOMPANYING THIS WAVE WILL BE A  
SURFACE LOW EJECTING OUT FROM THE LEE OF THE FRONT RANGE OF THE  
CO ROCKIES ACROSS THE PLAINS AND THROUGH CENTRAL IL/IN LATER  
SUNDAY. CONTINUE TO SEE A TREND IN THE LOW AND SUBSEQUENTLY ITS  
WARM FRONT TRACKING/REMAINING FARTHER SOUTH OF WI RESULTING IN  
PREVAILING EASTERLY AND COOLER FLOW ACROSS OUT NECK OF THE  
WOODS. HIGH TEMPS FOR SUNDAY LOOK TO RANGING FROM UPPER 60S TO  
LOWER 70S.  
 
WHILE THE SOUTHERN TREND BECOMES INCREASINGLY LIKELY SETUP FOR  
THE END OF THE WEEKEND, EXPECT TO STILL SEE PRECIP CHANCES TO  
DEVELOP ON THE COOL SIDE OF THE WARM FRONT AS WELL AS ON THE  
NORTHSIDE OF THE PASSING LOW AS THE MOISTURE FROM THE GULF  
ADVECTS UP THE MISSISSIPPI RIVER VALLEY WITH THIS SYSTEM.  
HOWEVER, THUNDERSTORM CHANCES CONTINUE TO DWINDLE UP IN SOUTHERN  
WI AS MODELS CONTINUE TO PROG THE FAVORABLE INSTABILITY TO  
SOUTH OF THE WI/IL BORDER ALONG AND SOUTH OF THE WARM FRONT  
MORE SO IN CENTRAL TO SOUTHERN IL/IN. ADDITIONALLY WITH THE  
SOUTHERN TREND, NORTHERN AND EVEN CENTRAL PORTIONS OF THE CWA  
MAY ULTIMATELY STAY DRY ON SUNDAY GIVEN THE DRIER AIR INFRINGING  
FURTHER SOUTH AS SEEN ON THE TAIL-END OF THE 00Z HRRR.  
NEVERTHELESS STILL LOOKING AT 30-60% CHANCE FOR SHOWERS FOR THE  
SOUTHERN PORTIONS OF THE CWA TOWARD THE WI/IL BORDER.  
 
ADDITIONALLY WITH THE ONSHORE FLOW OFF OF LAKE MICHIGAN SUNDAY  
INTO THE OVERNIGHT HOURS, COULD SEE ELEVATED SWIM RISK  
CONDITIONS AS WINDS PICK UP AND WAVES BUILD TOWARD HAZARDOUS  
LEVEL.  
 
WAGNER  
 

 
   
LONG TERM
 
 
ISSUED 1220 AM CDT SAT JUN 20 2026  
 
MONDAY THROUGH FRIDAY:  
 
CONTINUE TO SEE FAIRLY MILD TEMPS THAT WILL BE SLIGHTLY (3-10F)  
BELOW NORMAL THROUGH THE WEEKEND AS UPPER-LEVEL NORTHWESTERLY  
FLOW SETS UP ACROSS THE REGION. THIS PATTERN LOOKS TO CONTINUE  
INTO THE MIDDLE OF THE WEEK BEFORE UPPER-LEVEL RIDGE ATTEMPTS TO  
BUILD AND TEMPS WARM CLOSER TO NORMAL TOWARD THE LATER HALF OF  
THE WEEK. OVERALL EXPECTING A DRY START OF THE WEEK AS HIGH  
PRESSURE BUILDS DOWN ACROSS THE UPPER GREAT LAKE MONDAY AND  
TUESDAY. THEN MID-RANGE MODEL CONTINUE TO SHOW AN UPPER-LEVEL  
TROUGH DIGGING ACROSS THE REGION LATER TUESDAY INTO WEDNESDAY.  
THIS WILL BRING THE NEXT SHOT OF SHOWERS AND STORMS TO SOUTHERN  
WI. MAY SEE SOME OF THIS ACTIVITY LINGER INTO THURSDAY ON THE  
BACKSIDE OF THE DEPARTING SYSTEM, BUT OTHERWISE LOOKING AT HIGH  
PRESSURE TO BUILD TOWARD THE END OF THE WEEK ACCOMPANYING THE  
GRADUALLY WARMING TRENDS INTO NEXT WEEKEND.  
 
WAGNER  
 

 
   
AVIATION
 
 
ISSUED 500 AM CDT SAT JUN 20 2026  
 
AN ARC OF LOW CLOUDS (AROUND 1,500 TO 2,500 FT) HAS MANAGED TO  
PUSH SOUTHWARD INTO PORTIONS OF EAST CENTRAL WI EARLY THIS  
MORNING (MAINLY KSBM), RESULTING IN PATCHY MVFR. WE EXPECT  
THESE CLOUDS TO MIX OUT AND ERODE THROUGH THE COURSE OF DAYTIME  
HEATING. HENCE, DRY WEATHER AND VFR EXPECTED THROUGH TODAY AND  
TONIGHT. A LIGHT NORTHWEST BREEZE IS EXPECTED TODAY, WITH CALM  
WINDS TONIGHT.  
 
SHEPPARD  
 

 
   
MARINE
 
 
ISSUED 1220 AM CDT SAT JUN 20 2026  
 
LOW PRESSURE WILL WORKS ITS WAY EAST OVERNIGHT WHILE HIGH PRESSURE  
BEGINS TO BUILD INTO THE REGION. LOOKING AT LIGHTER WINDS TONIGHT  
THROUGH THE EARLY MORNING HOURS, BUT EXPECTING TO INCREASE THIS  
AFTERNOON IN BETWEEN THE DEPARTING LOW AND INCOMING HIGH. WINDS THEN  
SHIFT MORE EASTERLY FOR SUNDAY AS ANOTHER LOW PRESSURE DEVELOPS  
ACROSS THE PLAINS AND TRACKS ACROSS CENTRAL IL/IN. THE STRENGTHENING  
ONSHORE FLOW WILL LIKELY RESULT IN BUILDING WAVES AND GUSTY WINDS  
AROUND SMALL CRAFT LEVELS FOR SUNDAY INTO SUNDAY NIGHT, ESPECIALLY  
TOWARD THE SOUTHERN HALF OF THE LAKE. THEN LIGHTER WINDS RETURN FOR  
THE START OF THE WORK WEEK AS HIGH PRESSURE TREKS ACROSS THE  
AREA.  
 
WAGNER  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
LM...NONE.  

 
 

 
 
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