221  
FXUS63 KMKX 262340 AAA  
AFDMKX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
640 PM CDT FRI JUN 26 2026  
   
KEY MESSAGES  
 
- PATCHY FOG POSSIBLE TONIGHT, MAINLY ALONG THE LAKE MICHIGAN  
SHORELINE AND IN THE WISCONSIN RIVER VALLEY.  
 
- CHANCE FOR SHOWERS AND STORMS FOR LATE SUNDAY  
MORNING/AFTERNOON.  
 
- PROLONGED PERIOD OF HOT AND HUMID CONDITIONS EXPECTED FOR ALL  
OF NEXT WEEK. POTENTIAL FOR HEAT INDICES AROUND TO ABOVE  
100F.  
 
- ADDITIONAL SHOWER/STORM CHANCES ACCOMPANYING THE HEATWAVE  
TUESDAY THROUGH END OF WEEK  
 
 
   
UPDATE  
 
ISSUED 640 PM CDT FRI JUN 26 2026  
 
EASTERLY WINDS OFF LAKE MICHIGAN ARE KEEPING TEMPS IN THE 60S  
THERE, WHILE INLAND TEMPS ARE IN THE LOWER 70S. LOW CLOUDS AND  
PATCHY FOG ARE HUGGING THE LAKESHORE AND WILL PUSH INLAND AT  
TIMES THROUGH LATE EVENING. CANNOT RULE OUT SOME PATCHY FOG  
OVERNIGHT, MAINLY ALONG THE LAKESHORE AND ALSO IN THE WISCONSIN  
AND ROCK RIVER VALLEYS.  
 
CRONCE  
 
 
   
SHORT TERM  
 
ISSUED 138 PM CDT FRI JUN 26 2026  
 
TONIGHT THROUGH SATURDAY NIGHT:  
 
ZONAL UPPER-LEVEL FLOW AND A WEAK LOW PRESSURE TRACKING ACROSS  
CENTRAL IL BRINGING THE CLOUDY CONDITIONS THIS AFTERNOON WILL  
CONTINUE TO SHIFT EAST THIS EVENING. LOOKING AT LINGERING CLOUD  
COVER TO INSULATE THE AREA AND KEEP TEMPS OVERNIGHT A DEGREE OR  
TWO WARMER THAN PREVIOUS FORECAST WITH LOWS DIPPING LOW TO MID  
50S.  
 
THEN LOOKING A UPPER-LEVEL RIDGE BEGINS TO BUILD ACROSS THE  
REGION FOR SATURDAY. WILL BEGIN TO SEE WARMER TEMPS ALONG WITH  
HIGHER DEWPOINTS (UPPER 50S TO AROUND 60F) ADVECT INTO SOUTHERN  
WI. HOWEVER, EASTERLY ONSHORE FLOW ON THE BACKSIDE OF THE  
DEPARTING WEAK LOW AND NORTH OF A FRONTAL BOUNDARY WILL  
ULTIMATELY PREVENT THE WARMER TEMPS. ONLY LOOKING AT DAYTIME  
HIGHS IN THE MID TO UPPER 70S FOR AREAS ALONG AND EAST OF THE  
KETTLE MORAINE WHILE UPPER 70S TO LOW 80S FOR AREAS WEST/FURTHER  
INLAND FOR SATURDAY. WHILE EXPECT LESS CLOUD COVER FOR  
SATURDAY, CANNOT RULE OUT A FEW MORE PATCHES OF MID TO HIGH  
LEVEL CLOUDS FILL IN AS SUGGESTED BY 12Z HREF, WHICH COULD KNOCK  
DAYTIME TEMPS DOWN A FEW DEGREES. OTHERWISE, OVERNIGHT LOWS ARE  
TRENDING WARMER THAN THE PREVIOUS NIGHT WITH UPPER 50S TO LOW  
60S.  
 
WAGNER  
 
 
   
LONG TERM  
 
ISSUED 138 PM CDT FRI JUN 26 2026  
 
SUNDAY THROUGH FRIDAY:  
 
THE UPPER-LEVEL RIDGE CONTINUES TO BUILD ACROSS UPPER  
MISSISSIPPI RIVER VALLEY AND BRINGING THE WARMER AND MUGGIER  
CONDITIONS TO SOUTHERN WI. HOWEVER, MODELS CONTINUE TO HINT AT A  
MID-LEVEL VORTICITY MAX OVERRUNNING THE TOP OF THE BUILDING  
UPPER-LEVEL RIDGE AND TREKKING ACROSS THE REGION LATER SUNDAY  
MORNING. THE TAIL END OF THE 12Z CAMS ARE HINTING AT MCV TYPE  
STRUCTURE AND THIS DISTURBANCE PAIRED WITH THE LOW-LEVEL WAA  
AND INCREASING MOISTURE LOOKS TO BE ENOUGH FOR A SCATTERED  
SHOWERS AND STORMS CHANCES (20-40%) ACROSS SOUTHERN WI. GIVEN  
THE GENERAL TIMING OF LATE MORNING/EARLY AFTERNOON OF THIS  
FEATURE, THE NAM ALONG WITH GFS AND ECMWF ARE HINTING AT SOME  
INCREASED DEEP-LAYER SHEAR AND BUILDING INSTABILITY WITH MUCAPE  
CREEPING TOWARD 750-1200 J/KG WITH THIS SYSTEM. WHILE, DIFFICULT  
TO PINPOINT IF THESE FEATURES WILL LINE UP PAIRING WITH THE  
INFLUENCE FROM THE MCV, BUT IT IS NOT OUT OF THE REALM OF  
POSSIBILITY TO SEE A BIT MORE WIDESPREAD COVERAGE IN ACTIVITY  
THAN LATEST MODELS SUGGEST AND EVEN A POTENTIAL FOR A FEW  
STRONGER STORMS CANNOT BE RULED OUT, ESPECIALLY A SLIGHTLY LATER  
TIMING. WILL MONITOR AS CAMS COME MORE INTO RANGE.  
 
OTHERWISE, THE MAIN STORY OF THE EXTENDED WILL BE THE BUILDING  
HEAT RISK AS THE UPPER-LEVEL BLOCKING HIGH SETS UP OVER  
SOUTHEASTERN CONUS. MID AND LONG RANGE MODELS/ENSEMBLES CONTINUE  
TO TREND TOWARD THE HIGHER HEAT AND HUMIDITY BUILDING INTO THE  
AREA MORE MONDAY AND CONTINUE THROUGH MUCH OF NEXT WEEK. AT THIS  
TIME, MONDAY IS TRENDING TOWARD SEEING TRIPLE DIGIT HEAT  
INDICES, ESPECIALLY FOR WESTERN PORTION OF THE CWA. THEN THE  
RIDGE AXIS CONTINUE TO AMPLIFY TUESDAY THROUGH THURSDAY, WITH  
MORE WIDESPREAD TRIPLE DIGIT HEAT INDICES. GIVEN THE  
CONSISTENCY, PROLONGED NATURE OF THIS PATTERN ALONG WITH THIS  
BEING THE FIRST HEAT WAVE OF THE SUMMER, HEAT HEADLINES ARE  
LOOKING INCREASINGLY MORE LIKELY FOR NEXT WEEK AS THIS PATTERN  
BECOMES DANGEROUS FOR VULNERABLE POPULATIONS WITH HEALTH ISSUES  
AND/OR LACK OF COOLING/HYDRATION.  
 
LASTLY ACCOMPANYING THIS HEAT AND HUMID PATTERN FOR NEXT, WILL  
BE DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS AS UPPER-LEVEL  
DISTURBANCE MAY OVERRUN THE RIDGE. IF ANY SHOWERS/STORMS  
DEVELOP COULD END UP DISRUPTING THE TEMP FORECAST AND COULD  
LOWER HEAT INDICES WITH LINGERING CLOUDS AND RAIN COOLED AIR.  
 
WAGNER  
 
 
   
AVIATION  
 
ISSUED 640 PM CDT FRI JUN 26 2026  
 
MID LEVEL CLOUDS WITH A FEW DIURNAL CLOUDS REMAIN ACROSS  
SOUTHERN WI EARLY THIS EVENING. THERE ARE SOME LOW CLOUDS WITH  
BASES BETWEEN 400 AND 900 FT HUGGING THE LAKE MICHIGAN SHORELINE  
FROM MILWAUKEE TO KENOSHA AND THESE MAY PUSH INLAND AT TIMES  
THROUGH LATE EVENING TO AFFECT MKE, RAC AND ENW AIRPORT  
TERMINALS. CONFIDENCE IS LOW FOR HOW THE LAKE STRATUS/FOG WILL  
ACT OVERNIGHT, BUT CURRENT INDICATIONS ARE THAT IT WILL REMAIN  
OFFSHORE.  
 
EXPECT MORE MID LEVEL CLOUDS WITH A FEW DIURNAL CUMULUS CLOUDS  
AGAIN SATURDAY. CANNOT RULE OUT A FEW LOW CLOUDS NEAR THE LAKE  
DUE TO THE PERSISTENT ONSHORE FLOW.  
 
CRONCE  
 
 
   
MARINE  
 
ISSUED 138 PM CDT FRI JUN 26 2026  
 
HIGH PRESSURE OVER THE THE GREAT LAKES WILL KEEP WINDS LIGHTER  
TONIGHT INTO SATURDAY, BUT GRADUALLY PICK UP AS THE HIGH  
PRESSURE SLIDES EAST. WILL THEN SEE WINDS PICK UP FOR THE LATER  
HALF OF THE WEEKEND AS LOW PRESSURE DEEPENS OVER THE PLAINS AND  
MORE SOUTHERLY WINDS PICK UP FOR THE START OF NEXT WEEK. COULD  
SEE STRONGER GUSTS UP 30 KNOTS AT TIMES AS THE HEAT WAVES  
PERSISTS ACROSS THE REGION. WITH THESE GUSTY WINDS, SMALL CRAFT  
CONDITIONS WILL BE POSSIBLE AT TIMES THROUGH NEXT WEEK.  
 
WAGNER  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
VISIT US AT WEATHER.GOV/MILWAUKEE  
 
FOLLOW US ON FACEBOOK, X, AND YOUTUBE AT:  
WWW.FACEBOOK.COM/NWSMILWAUKEE  
WWW.X.COM/NWSMILWAUKEE  
WWW.YOUTUBE.COM/NWSMILWAUKEE  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WI Page
Main Text Page