222  
FXUS63 KMKX 190144  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
844 PM CDT MON MAY 18 2026  
   
KEY MESSAGES  
 
- ANOTHER ROUND OF SHOWERS AND STORMS LATE TONIGHT INTO TUESDAY  
WITH A SMALL POTENTIAL FOR STRONG TO SEVERE STORMS.  
 
- COOL AND DRIER WEATHER THEN RETURNS FOR MIDWEEK.  
 
- RAIN CHANCES RETURN FRIDAY (45-55%), FOLLOWED BY A GRADUAL  
WARMING TREND SATURDAY INTO EARLY NEXT WEEK.  
 
 
   
UPDATE  
 
ISSUED 844 PM CDT MON MAY 18 2026  
 
THE STRONG TO SEVERE MCS OVER SOUTH CENTRAL IA WILL ONCE AGAIN  
ENCOUNTER MUCH GREATER MLCIN AND HIGH LFCS AS IT CONTINUES NEWD  
TOWARD THE MS RIVER. THUS A DISSIPATING MCS WILL LIKELY MOVE  
INTO SW WI AFTER MIDNIGHT. HOWEVER, STILL EXPECT FAIRLY  
WIDESPREAD SHOWERS AND SCT STORMS TO MOVE ACROSS ALL OF SRN WI  
DURING THE EARLY MORNING HOURS AS A SSWLY LOW LEVEL JET OF 40  
KTS INCREASES WARM, MOIST ADVECTION AND BOOSTS ELEVATED CAPE TO  
1000-2000 J/KG. WIND GUSTS WILL BE THE MAIN CONCERN WITH ANY  
STORMS.  
 
A WAVE OF LOW PRESSURE ALONG THE STATIONARY FRONT OVER IA WILL  
TRACK NEWD TO WEST CENTRAL WI BY 06Z THEN NEAR LAKE SUPERIOR BY  
12Z TUE. THE LOW WILL THEN TRACK EWD INTO QUEBEC DURING THE DAY  
WITH ITS TRAILING COLD FRONT MOVING ACROSS SRN WI TUE AM INTO  
THE EARLY AFTERNOON. MOIST LOW LEVELS AND MARGINAL INSTABILITY  
COULD RESULT IN A BROKEN LINE OF SHOWERS AND ISOLD STORMS ALONG  
THE FRONT BUT NO SEVERE WX IS ANTICIPATED.  
 
GEHRING  
 
 
   
SHORT TERM  
 
ISSUED 200 PM CDT MON MAY 18 2026  
 
LATE THIS AFTERNOON THROUGH TUESDAY NIGHT:  
 
QUIET WEATHER LARGELY EXPECTED THE REST OF THE AFTERNOON INTO  
THE EVENING WITH REMNANT CONVECTION MOVING OFF TO THE EAST WITH  
QUITE A BIT OF CLEARING ONGOING RIGHT NOW AHEAD OF DEVELOPING  
STORMS TO THE SOUTHWEST THIS AFTERNOON AND EVENING. THIS IS WHAT  
WE WILL BE MONITORING TONIGHT AS IT PUSHES INTO THE CWA. BASED  
ON THE DEVELOPMENT OF THIS CONVECTION WILL IN PART DETERMINE HOW  
THINGS PLAY OUT TONIGHT. SEVERAL MODELS FAVOR DEVELOPMENT AND  
PROGRESSION INTO A QLCS WITH A EASTWARD PROGRESSION. MOST  
MODELS HAVE THIS POTENTIALLY BECOMING ELEVATED IN ADDITION TO  
LIMITED INSTABILITY. AS THIS PUSHES EAST TOWARD SOUTHEAST WI  
CAMS LARGELY HAVE THIS FALLING APART WITH VERY LIMITED  
INSTABILITY AND VERY LIKELY AN ELEVATED SYSTEM AT THAT POINT,  
WHICH WOULD REDUCE SEVERE RISK TO ESSENTIALLY ZERO. HOWEVER, IT  
IS WORTH MENTIONING THAT CLEARING THIS AFTERNOON HAS DEFINITELY  
INCREASED OUR SEVERE RISK AS WE WILL LIKELY BE ABLE TO HANG ON  
TO A BIT MORE INSTABILITY AND MAY AVOID STORMS IMMEDIATELY  
BECOMING ELEVATED AS THEY REACH THE CWA. THE BEST SEVERE RISK  
FOR TONIGHT WILL BE IN SOUTHWEST WI, LIKELY SOUTHWEST OF  
MADISON, WITH DECREASING RISK FURTHER EAST. WE WILL NEED TO  
MONITOR STORMS TO THE SOUTHWEST TONIGHT AS THE DEVELOPMENT AND  
PROGRESSION WILL PLAY A ROLE IN DETERMINING THE POTENTIAL FOR  
SEVERE STORMS LATER TONIGHT.  
 
THE REMNANT STORMS AND PRECIP WILL PUSH OUT BY MID MORNING WITH  
OUR ATTENTION TURNING TO THE COLD FRONT THAT WILL CLOSELY  
FOLLOWING THE EXITING PRECIP. THERE IS A MILD CONCERN FOR  
DEVELOPING STORMS ALONG THE FRONT BUT WITH DEPARTING STORMS IN  
THE MORNING IT DOES NOT APPEAR THERE WILL ANY RECOVERY TIME  
AHEAD OF THE FRONT WITH MODELS SUGGESTING VERY LIMITED  
INSTABILITY AND FRANKLY NOT A GREAT SHEAR ENVIRONMENT EITHER.  
THIS SUGGESTS THAT EVENT SHOULD WEEK STORMS DEVELOP THEY WOULD  
NOT LIKELY BE OF CONCERN. THE FRONT SHOULD PUSH IN BY THE LATE  
MORNING AND PUSH THROUGH ALL OF SOUTHERN WI BY EARLY TO MID  
AFTERNOON. THE BEST CHANCE FOR WEAK STORM DEVELOPMENT WITH THE  
FRONT IS LIKELY IN SOUTHEAST WI WHERE THE BEST CHANCE FOR  
RECOVERY WOULD BE. OTHERWISE, EXPECT QUIET CONDITIONS INTO THE  
LATE AFTERNOON AND OVERNIGHT AS WINDS TURN NORTHWEST BEHIND THE  
FRONT WITH HIGHER PRESSURE GRADUALLY PUSHING BEHIND IT.  
 
KUROSKI  
 
 
   
LONG TERM  
 
ISSUED 200 PM CDT MON MAY 18 2026  
 
WEDNESDAY THROUGH MONDAY:  
 
COOL AND DRY WEATHER EXPECTED WEDNESDAY AND THURSDAY, WITH STRONG  
HIGH PRESSURE PASSING OVERHEAD AND NORTHEAST TO EAST WINDS OFF OF  
LAKE MICHIGAN (AROUND 10 TO 15 MPH AT TIMES). MUCH OF EASTERN WI  
SHOULD SEE HIGHS IN THE 50S, WITH LOW TO MID 60S FURTHER WEST.  
SOME MUCH NEEDED CALM AND QUIET WEATHER.  
 
OUR NEXT NOTEWORTHY CHANCE FOR PRECIPITATION ARRIVES FRIDAY, WITH  
ROUGHLY HALF OF THE AVAILABLE MODEL GUIDANCE RESOLVING A LOW  
PRESSURE SYSTEM TRACKING NORTHEASTWARD FROM THE GREAT PLAINS AND  
APPROACHING OUR REGION. THE FAVORED TRACK OF THIS SYSTEM WOULD  
STALL IT EITHER TO OUR SOUTH OR OUR WEST, WITH THE CONTINUED  
ONSHORE FLOW FROM LAKE MICHIGAN HELPING TO REDUCE INSTABILITY AND  
PREVENT SUBSTANTIAL MOISTURE RETURN OVER SOUTHERN WI. HENCE, WE  
ONLY FORECAST SLIGHT CHANCES FOR THUNDERSTORMS FRIDAY, WITH RAIN  
CHANCES INCREASING FROM 15-55% IN A SOUTHWEST TO NORTHEAST MANNER  
AS THE DAY GOES BY. AS WITH ANY LOW PRESSURE SYSTEM THIS TIME OF  
YEAR, WE WILL HAVE TO KEEP AN EYE ON IT'S TRACK AND EVOLUTION,  
BUT ENSEMBLE CONSENSUS STRONGLY SUGGESTS INSUFFICIENT MOISTURE  
RETURN / INSTABILITY FOR MUCH IN THE WAY OF THUNDER.  
 
PREDICTABILITY DROPS SUBSTANTIALLY FOR SATURDAY AND ONWARDS, BUT  
THE GENERAL CONSENSUS IS A WARMING TREND THAT CONTINUES INTO EARLY  
NEXT WEEK.  
 
SHEPPARD  
 
 
   
AVIATION  
 
ISSUED 844 PM CDT MON MAY 18 2026  
 
VFR CONDITIONS THIS EVENING THEN NUMEROUS SHOWERS AND SCATTERED  
STORMS DURING THE EARLY MORNING HOURS. AREAS OF MVFR CIGS AND  
VSBYS MAY LINGER AFTER THE RAIN. MORE WIDESPREAD MVFR CIGS WILL  
THEN OVERSPREAD SRN WI JUST AFTER SUNRISE AND AHEAD OF THE  
APPROACHING COLD FRONT. LOCALIZED CIGS BELOW 1 KFT ARE POSSIBLE  
OVER SOUTH CENTRAL WI. THE CIGS WILL DISSIPATE AFTER THE COLD  
FRONTAL PASSAGE FROM MID TO LATE AFTERNOON. GUSTY SWLY WINDS TO  
30 KTS ARE EXPECTED ON TUE ESPECIALLY OVER ERN WI.  
 
GEHRING  
 
 
   
MARINE  
 
ISSUED 844 PM CDT MON MAY 18 2026  
 
A DENSE FOG ADVISORY IS IN EFFECT TONIGHT THROUGH TUESDAY MORNING  
FOR THE NORTH HALF OF THE LAKE AS RELATIVELY MILD AND HUMID AIR  
FLOWS OVER THE COLD LAKE WATERS. OTHERWISE MODEST TO BREEZY  
SOUTHERLY WINDS WILL DEVELOP TONIGHT AND LAST INTO EARLY TUESDAY  
AFTERNOON, THEN FOLLOWED BY THE PASSAGE OF A COLD FRONT. WINDS  
WILL SHIFT TO NORTHWESTERLY WITH THE COLD FRONTAL PASSAGE AND  
REMAIN A BIT BREEZY. SCATTERED THUNDERSTORMS CAN BE EXPECTED OVER  
THE CENTRAL AND SOUTHERN PORTION OF THE LAKE LATE TONIGHT INTO  
TUESDAY. HIGH PRESSURE AROUND 30.4 INCHES WILL THEN MOVE INTO  
THE NORTHERN GREAT LAKES FOR WEDNESDAY AFTERNOON INTO THURSDAY.  
LIGHT AND VARIABLE WINDS TAKING HOLD FROM LATE WEDNESDAY INTO  
THURSDAY. A SMALL CRAFT ADVISORY IS IN EFFECT FROM SHEBOYGAN TO  
WINTHROP HARBOR FROM EARLY MORNING TUESDAY INTO THE AFTERNOON  
FOR BREEZY SOUTHWEST WINDS.  
 
GEHRING  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646...4 AM  
TUESDAY TO 4 PM TUESDAY.  
 
DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-  
LMZ567-LMZ868 UNTIL NOON TUESDAY.  
 
 
 
 
 
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