489  
FXUS63 KMKX 200426  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
1126 PM CDT SUN APR 19 2026  
   
KEY MESSAGES
 
 
- FROST EXPECTED OVERNIGHT INTO EARLY MONDAY MORNING, WITH LOW  
TEMPS IN THE MID TO UPPER 20S. THOSE WITH SENSITIVE PLANTS  
SHOULD COVER THEM TONIGHT.  
 
- TEMPS RISE WELL ABOVE NORMAL TUESDAY THROUGH THURSDAY.  
 
- NEXT CHANCES (50-80%) FOR SHOWERS AND THUNDERSTORMS THURSDAY  
NIGHT.  
 

 
   
SHORT TERM
 
 
ISSUED 1130 PM CDT SUN APR 19 2026  
 
TODAY THROUGH TUESDAY NIGHT:  
 
LOWS THIS MORNING IN THE MID 20S TO LOW 30S COMBINED WITH CALM  
WINDS AND CLEAR SKIES WILL ALLOW FOR WIDESPREAD FROST  
DEVELOPMENT THIS MORNING, BURNING OFF SHORTLY AFTER SUNRISE.  
HIGH CLOUDS ARE EXPECTED TO MOVE IN BY THE AFTERNOON HOURS, WITH  
SOUTH- SOUTHWESTERLY WINDS INCREASING THROUGH THE DAY AS HIGH  
PRESSURE EXITS TO THE SOUTHEAST AND LOW PRESSURE PROPAGATES  
THROUGH NORTHERN MANITOBA. GUSTS AROUND 20 MPH ARE EXPECTED,  
WITH HIGHS IN THE LOW 50S. TEMPERATURES OVERNIGHT ARE ONLY  
EXPECTED TO DIP INTO THE LOW 40S, AS SOUTHWESTERLY WINDS  
CONTINUE.  
 
A WEAK FRONTAL BOUNDARY FROM THE NORTHERN LOW WILL PROPAGATE  
THROUGH SOUTHERN WISCONSIN TUESDAY MORNING. A FEW SHOWERS ARE  
POSSIBLE ACROSS FAR SOUTHERN WISCONSIN AS THE FRONT STALLS, BUT  
CONFIDENCE IS LOW WITH PLENTY OF DRY AIR IN THE 700 MB TO  
SURFACE LAYER. MAJORITY OF THIS PRECIPITATION WOULD EVAPORATE  
BEFORE REACHING THE GROUND. EXPECTING HIGHS IN THE 70S AS  
SOUTHERLY WINDS CONTINUE. A LAKE BREEZE MAY CONTRIBUTE TO HIGHS  
IN THE MID 60S NEAR LAKE MICHIGAN. TUESDAY EVENING, THE COLD  
FRONT FROM THE NORTHERN LOW WILL SWEEP THROUGH SOUTHERN  
WISCONSIN FROM NORTHEAST TO SOUTHWEST. EXPECT LOWS IN THE MID  
40S TO UPPER 30S, WITH THE LOWEST TEMPERATURES IN THE  
SHEBOYGAN/FOND DU LAC AREAS.  
 
MH  
 

 
   
LONG TERM
 
 
ISSUED 1130 PM CDT SUN APR 19 2026  
 
WEDNESDAY THROUGH SUNDAY:  
 
SECOND HALF OF THE WEEK WILL BE A WARM ONE. TEMPS QUICKLY  
RECOVER ON WEDNESDAY AS THE THE UPPER-LEVEL RIDGE AXIS WORKS ITS  
WAY ACROSS THE REGION. GIVEN THE HIGH PROBABILITIES (+80%) FROM  
THE GEFS, ENS, AND GEPS, EXPECT DAYTIME TEMPS TO WARM BACK INTO  
THE 70S FOR WEDNESDAY AND EVEN A POTENTIAL FOR UPPER 70S AND  
MAYBE EVEN CRACK 80F ON THURSDAY. HOWEVER, ANY EASTERLY WIND OFF  
OF LAKE MICHIGAN WILL KEEP THINGS SEVERAL DEGREES COOLER ALONG  
THE LAKESHORE TO THE KETTLE MORAINE, WHILE FURTHER INLAND WILL  
LIKELY SEE THE WARMEST TEMPS. OVERNIGHT TEMPS ARE ALSO LOOKING  
MILDER FOR THIS TIME OF YEAR RANGING FROM UPPER 40S TO LOWER 60S  
THROUGH THE END OF THE WEEK.  
 
ACCOMPANYING THIS WARM STRETCH WILL BE ANOTHER POTENTIAL FOR  
SHOWERS AND THUNDERSTORMS AS AN UPPER-LEVEL TROUGH SWINGS ACROSS  
THE THE NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY FOR  
THURSDAY INTO FRIDAY. THE LONG RANGE MODELS CONTINUE A TREND  
PIVOTING THE MID- LEVEL TROUGH BACK NORTHWARD AS ANOTHER TROUGH  
TRIES TO PHASE WITH IT. GIVEN THIS TREND, EXPECT TO SEE THE  
SURFACE LOW FOLLOW SUIT AND LIKELY TRACK ACROSS THE DAKOTAS AND  
LIFT INTO MANITOBA/NORTHWESTERN ONTARIO LATER THURSDAY. WHILE  
SOUTHERN WI WILL BE ON THE WARM SIDE OF THIS SYSTEM WITH  
INSTABILITY BUILDING TOWARD 1000J/KG, THE BETTER UPPER-LEVEL  
FORCING ALONG WITH MORE FAVORABLE SHEAR LOOKS TO REMAIN TO THE  
WEST-NORTHWEST CLOSE TO THE CENTER OF THE LOW ITSELF. THUS, THE  
MORE FAVORABLE SETUP FOR SEVERE THUNDERSTORM ACTIVITY LOOKS TO  
REMAIN ALONG AND WEST OF THE UPPER MISSISSIPPI RIVER VALLEY AT  
THIS TIME. MAY SEE THE DECAYING REMNANTS OF THIS ACTIVITY WORK  
ITS WAY INTO THE WESTERN HALF OF THE AREA LATER THURSDAY. WHILE  
THERE IS FAIRLY CONSISTENT AGREEMENT ON THE LONG-RANGE ENSEMBLES  
AS WELL AS THE ML SEVERE PROBS FOR THINGS TO REMAIN JUST  
OUTSIDE OUR AREA, WE ARE STILL SEVERAL DAYS OUT AND WILL BE  
MONITORING FOR ANY EASTWARD SHIFT IN THE TRENDS.  
 
FRIDAY IS TRENDING WARMER, BUT THE COLD FRONT ASSOCIATED WITH  
THE THURSDAY SYSTEM IS PROGGED TO GRADUALLY WORK ITS WAY ACROSS  
SOUTHERN WI THROUGH THE DAY. THIS WILL BRING COOLER AIRMASS TO  
THE REGION FOR THE WEEKEND UNDER MAINLY ZONAL UPPER-LEVEL FLOW.  
HOWEVER, NOT EXPECTING AS COLD OF TEMPS AS WE SAW WITH THIS PAST  
WEEKEND SYSTEM, BUT GENERALLY LOOKING AT TEMPS CLOSER TO  
NORMAL.  
 
WAGNER  
 

 
   
AVIATION
 
 
ISSUED 1130 PM CDT SUN APR 19 2026  
 
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE TAF PERIOD, WITH A  
FEW LINGERING CLOUDS AROUND 9000 FT CLEARING TONIGHT, AND THEN  
HIGH CLOUDS AROUND 15,000 TO 25,000 FT MOVING IN DURING THE  
AFTERNOON HOURS TODAY. A FEW CLOUDS AROUND 5000 FT ARE POSSIBLE,  
AND THESE MAY PRODUCE A FEW SPRINKLES DURING THE AFTERNOON  
HOURS IN FAR SOUTHERN WISCONSIN.  
 
LIGHT AND VARIABLE TO CALM WINDS THROUGH MID-MORNING, BECOMING  
SOUTHWESTERLY AND GUSTY AROUND 15 TO 20 KT BY AFTERNOON. LAKE  
MICHIGAN TERMINALS WILL SEE SOUTHERLY TO SOUTHEASTERLY WINDS,  
STILL GUSTING BETWEEN 15 AND 20 KT. WINDS WILL REMAIN GUSTY BUT  
BECOME SOUTHERLY INTO TONIGHT, SHIFTING BACK TO SOUTHWESTERLY  
INTO TUESDAY MORNING.  
 
MH  
 

 
   
MARINE
 
 
ISSUED 1130 PM CDT SUN APR 19 2026  
 
HIGH PRESSURE AROUND 30.4 INCHES WILL BRING LIGHT AND VARIABLE  
WINDS THROUGH THIS MORNING, WITH WINDS SHIFTING TO SOUTHERLY  
INTO THIS AFTERNOON AS HIGH PRESSURE EXITS INTO THE OHIO VALLEY.  
LOW PRESSURE AROUND 29.5 INCHES WILL PROGRESS THROUGH NORTHERN  
MANITOBA INTO THE HUDSON BAY FROM THIS MORNING THROUGH TUESDAY  
MORNING, SLOWLY SHIFTING WINDS SOUTHWESTERLY AND BRINGING GUSTS  
AROUND 30 KT TONIGHT THROUGH TUESDAY MORNING. IN THE NORTHERN  
THIRD OF THE LAKE, POTENTIAL FOR A FEW GALE FORCE GUSTS EXISTS.  
WINDS WILL SHIFT TO BECOME NORTHEASTERLY AS A COLD FRONT SWEEPS  
NORTH TO SOUTH THROUGH THE LAKE TUESDAY NIGHT INTO WEDNESDAY  
MORNING. HIGH PRESSURE OF 30.1 INCHES BUILDS INTO ONTARIO  
WEDNESDAY, BRINGING LIGHTER AND VARIABLE WAVES ACROSS THE LAKE.  
LOW PRESSURE THEN DEVELOPS IN THE LEE OF THE ROCKIES AND DEEPENS  
TO 29.1 INCHES, BRINGING GUSTY SOUTHEASTERLY WINDS TO LAKE  
MICHIGAN THURSDAY THROUGH FRIDAY. LOW PRESSURE EJECTS INTO THE  
CANADIAN PRAIRIES FRIDAY NIGHT, BRINGING A COLD FRONT THROUGH  
LAKE MICHIGAN AND BRINGING A RETURN TO NORTHWESTERLY WINDS.  
THUNDERSTORMS ARE POSSIBLE ALONG THIS FRONT. SATURDAY WILL SEE  
CONTINUED LIGHT NORTHERLY WINDS.  
 
MH  
 

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

 
 

 
 
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