038  
FXUS63 KMKX 290034  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
734 PM CDT SUN JUN 28 2026  
   
KEY MESSAGES  
 
- EXTREME HEAT WARNING IN EFFECT FOR ALL OF SOUTHERN WI MONDAY  
AFTERNOON THROUGH TUESDAY. ADDITIONAL HEAT HEADLINES WILL  
LIKELY BE NEEDED FOR THE MIDDLE TO LATE PORTIONS OF THE WEEK  
AS THIS PROLONGED HEATWAVE CONTINUES.  
 
- CONTINUED CHANCES FOR SHOWERS AND STORMS TONIGHT ESPECIALLY  
FOR EAST-CENTRAL WI. THEN ADDITIONAL DAILY STORM CHANCES  
TUESDAY NIGHT THROUGH THE END OF THE WEEK AS THE HOT AND HUMID  
PATTERN CONTINUES.  
 
- HIGH SWIM RISK CONDITIONS FOR OZAUKEE AND SHEBOYGAN COUNTY  
BEACHES ON MONDAY, WHILE MODERATE SWIM RISK CONDITIONS FOR  
MILWAUKEE, RACINE, AND KENOSHA COUNTIES.  
 
 
   
UPDATE  
 
ISSUED 734 PM CDT SUN JUN 28 2026  
 
PERSISTENT MID LEVEL WARM ADVECTION AND FRONTOGENESIS CONTINUES  
TO TRIGGER SHOWERS AND STORMS NORTH OF MILWAUKEE TO MANITOWOC,  
BUT THERE HAS BEEN A DECREASE IN COVERAGE. ISOLATED TO SCATTERED  
DEVELOPMENT MAY CONTINUE THROUGH THE EVENING. FARTHER TO THE  
WEST A SLY LOW LEVEL JET AROUND 35-40 KT OVER ERN IA WILL SHIFT  
NWD IN CENTRAL WI. THUS NEW ELEVATED SHOWERS AND STORMS WILL  
DEVELOP OVER THIS REGION DUE TO THE LOW TO MID LEVEL WARM, MOIST  
ADVECTION AND EMBEDDED FRONTOGENESIS. THE LOW LEVEL JET WILL  
GRADUALLY VEER TO SWLY THROUGH THE NIGHT THEN WEAKEN TOWARD  
DAYBREAK. BELIEVE THE 12C ISOTHERM AT 700 MB WILL REMAIN A GOOD  
INDICATOR OF CAPPING TO THE SOUTH, WHILE ENOUGH LIFT AND  
MOISTURE FOR STORMS WILL PREVAIL TO THE NORTH. THUS EAST CENTRAL  
WI WILL AT LEAST BE ON THE SRN PERIPHERY OF THIS NEW AREA OF  
CONVECTION. FORECASTING 50 PERCENT CHANCES TOWARD CENTRAL WI  
LATE THIS EVENING AND OVERNIGHT WITH ONLY SLIGHT CHANCES FROM  
MADISON TO MILWAUKEE.  
 
THE SURFACE WARM FRONT WILL THEN PASS NWD THROUGH SRN WI FROM  
09-15Z MON AS LOW PRESSURE TRACKS FROM THE CENTRAL HIGH PLAINS  
INTO THE DAKOTAS. A HOT, HUMID, AND WELL CAPPED AIRMASS WILL  
THEN PREVAIL FOR MON-TUE. HIGH TEMPS IN THE LOWER TO MIDDLE 90S  
WITH DEWPOINTS IN THE MIDDLE 70S WILL YIELD HEAT INDEX VALUES OF  
100-110F. AN EXTREME HEAT WARNING IS IN EFFECT.  
 
GEHRING  
 
 
   
SHORT TERM  
 
ISSUED 245 PM CDT SUN JUN 28 2026  
 
TONIGHT THROUGH TUESDAY NIGHT:  
 
REMNANT MCS IS TREKKING ACROSS SOUTHERN WI THIS AFTERNOON  
FOLLOWING ALONG THE BAND OF 700 MB FRONTOGENESIS AND MID-LEVEL  
SHORTWAVE TROUGH. WHILE IT IS MAINLY BRINGING LIGHT TO MODERATE  
RAINFALL WITH THE STRONGER ACTIVITY FOLLOWING THE BETTER SBCAPE  
GRADIENT AND WARM FRONT INTO NORTHERN IL, THERE HAS BEEN ENOUGH  
ELEVATED INSTABILITY OVER SOUTHERN WI FOR A FEW FLASHES OF  
LIGHTNING AND RUMBLES OF THUNDER TO OCCUR WITHIN THE STRATIFORM  
REGION OF THIS COMPLEX. CANNOT COMPLETELY RULE OUT SEEING THIS  
LINE REINVIGORATE SOME AS IT MOVES TOWARD THE LAKE AS THIS AREA  
HAS HAD SOME TIME TO WARM UP AND BUILD UP A BIT MORE INSTABILITY  
(MUCAPE OF AROUND 500MB BASED ON 18Z RAP) AND PAIRED WITH THE  
SYNOPTIC FORCING MECHANISMS AND LOCALIZED MCV FORCING. WILL BE  
MONITORING RADAR TRENDS AND SEE IF THIS MATERIALIZES, IF SO  
COULD SEE SOME GUSTY WINDS. IN ADDITION TO THE LIGHTNING  
THREAT. OTHERWISE, EXPECT THIS SHOWER AND OCCASIONAL THUNDER  
ACTIVITY TO WORK EAST THROUGH THE REMAINDER OF THE AFTERNOON AND  
PUSHING OUT BY THE EVENING.  
 
THEN WILL BE ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS THIS  
EVENING MAINLY ACROSS THE CENTRAL AND EAST-CENTRAL WI NORTH OF  
I-94 AS THE WARM FRONT LIFTS NORTHWARD AND LOW-LEVEL WAA JOINS  
THE REMNANT 700 MB FRONTOGENESIS BAND AND NOSE OF 30-45KT LLJ.  
MUCH OF THIS ACTIVITY LOOKS WIDELY SCATTERED WITH LIGHT TO  
MODERATE RAINFALL. THIS ACTIVITY SHOULD PROGRESS NORTHWARD AND  
EXIT OUR CWA AROUND DAYBREAK, BUT LINGERING CLOUD COVER MAY  
PERSIST THROUGH THE START OF THE MORNING.  
 
OTHERWISE, THE UPPER-LEVEL RIDGE AXIS CONTINUES TO BUILD OVER  
THE REGION INTO MONDAY WITH OVERNIGHT LOWS TONIGHT STARTING OF  
IN THE UPPER 60S TO LOWER 70S. THEN CONTINUE TO SEE THE HOT AND  
HUMID CONDITIONS SETTLING IN OVER THE MIDWEST. WHILE ANY  
LINGERING CLOUD COVER MAY SLOW THE MORNING TEMPS, EXPECT THINGS  
TO CLEAR UP MID-LATE MORNING WITH TEMPS QUICKLY CLIMBING INTO  
THE 80S AND 90S BY THE AFTERNOON. PAIR WITH THE DEWPOINTS IN THE  
LOWER 70S, HEAT INDICES OF +100F IS EXPECTED ACROSS MUCH OF THE  
AREA AND EVEN EXPECTING TO SEE +105F HEAT INDICES. AREAS RIGHT  
ALONG AND JUST INLAND OF LAKE MICHIGAN WILL SEE THE COOLEST  
CONDITIONS, BUT STILL HAZARDOUS HEAT. THUS HAVE UPGRADED AND  
ISSUED AN EXTREME HEAT WARNING FOR ALL OF SOUTHERN WI MONDAY  
AFTERNOON.  
 
HAVE ELECTED TO CONTINUE THE EXTREME HEAT WARNING MONDAY  
EVENING/NIGHT AS THERE IS NOT EXPECTED TO BE MUCH RELIEF FROM  
THE HEAT WITH OVERNIGHT LOWS EXPECTED IN THE MID TO UPPER 70S  
AND EVEN WARMER HEAT INDICES. ALSO HAVE EXTENDED THE WARNING  
INTO TUESDAY AS SOUTHERN WILL SEE ANOTHER HOT AND HUMID DAY FOR  
TUESDAY AS THE BLOCKING HIGH OVER SOUTHEASTERN CONUS KEEPS THE  
UPPER-LEVEL RIDGE OVER THE UPPER MIDWEST. LOOKING AT AFTERNOON  
TEMPS IN THE MID 90S AND +100F HEAT INDICES. WHILE CANNOT RULE  
OUT FEW STRAY SHOWERS AND STORMS TO DEVELOP IN THIS MUGGY  
ENVIRONMENT, THERE IS NOT MUCH IN THE WAY OF FORCING TO TRIGGER  
THIS ACTIVITY UNTIL LATER TUESDAY.  
 
OVERALL, THE WEEK WILL START OFF WITH A PROLONGED PERIOD OF  
HEAT PAIRED WITH HUMID CONDITIONS RESULTING IN HEAT RELATED  
ISSUES AND CONCERNS. STAY WEATHER AWARE AND KEEP COOL AND  
HYDRATED.  
 
LASTLY INCREASING SOUTHERLY ONSHORE FLOW DEVELOPING OVERNIGHT  
INTO MONDAY WILL BUILD WAVES ALONG SOUTHEASTERN WI BEACHES  
RESULTING IN ELEVATED SWIM RISK CONDITIONS. HIGHEST WAVES OF 4-6  
FEET AND CONDITIONS FAVORING DANGEROUS CURRENTS WILL BE FOR  
SHEBOYGAN AND OZAUKEE COUNTY BEACHES MONDAY. STILL LOOKING AT  
MODERATE SWIM RISK CONDITIONS FOR BEACHES SOUTH ALONG MILWAUKEE  
AND RACINE COUNTY BEACHES.  
 
WAGNER  
 
 
   
LONG TERM  
 
ISSUED 245 PM CDT SUN JUN 28 2026  
 
WEDNESDAY THROUGH SUNDAY:  
 
MIDWEEK ONWARD IS EXPECTING TO SEE SIMILAR SET UP WITH THE  
UPPER- LEVEL RIDGE SITUATED OVER THE GREAT LAKES THROUGH THE END  
OF THE WEEK. THUS, WILL CONTINUE TO SEE HOT AND HUMID  
CONDITIONS WITH DAYTIME HEAT INDICES IN THE UPPER 90S TO  
AROUND/ABOVE 100F. ADDITIONAL HEAT HEADLINES ARE POSSIBLE FOR  
THE SECOND HALF OF THE WEEK. HOWEVER, THE BIGGEST DIFFERENCE  
FROM THE START OF THE WEEK THROUGH THE END OF THE WEEK, IS THE  
INCREASED CHANCES FOR DAILY SHOWERS AND THUNDERSTORMS. AS NOTED  
YESTERDAY MODELS HAVE THE RIDGE AXIS SLIGHTLY FURTHER EAST THAN  
EARLIER MODEL RUNS, PLACING THE SOUTHERN WI UNDER THE  
PERIPHERALS AND EVEN WITHIN THE UPPER-LEVEL JET. ANY SHOWER AND  
STORM ACTIVITY, DEPENDING ON TIMING/DEVELOPMENT AS WELL AS  
REMNANT CLOUD COVER MAY INFLUENCE TEMPS AS WELL AS HEAT INDICES  
EACH DAY WEDNESDAY THROUGH FRIDAY. THUS, NOT AS CERTAIN ON THE  
HIGHER HEAT INDICES AT THIS POINT AND ADDITIONAL HEAT HEADLINES  
(WARNING/ADVISORY) DECISION WILL BE TAKEN DAY-BY-DAY.  
 
REGARDLESS OF THE HEAT HEADLINES/THRESHOLDS AND STORM CHANCES,  
STILL LOOKING AT PERIODS OF DAYTIME HEAT INDICES IN AT LEAST THE  
90S AND ABOVE EACH DAY ALONG WITH WARM NIGHTLY LOWS FOR THE END  
OF THE WEEK. THUS, PROLONGED NATURE OF THE PATTERN DUE TO THE  
BLOCKING HIGH WILL LIKELY BE CASE FOR CONTINUED HEAT RELATED  
ISSUES/CONCERN ACROSS SOUTHERN WI, ESPECIALLY FOR VULNERABLE  
POPULATIONS WITHOUT EASY ACCESS TO STAY COOL AND THOSE SPENDING  
EXTENDED PERIODS OUTSIDE.  
 
THERE ARE SOME HINTS IN THE LONG-RANGE MODELS OF THE RIDGE  
BREAKING DOWN A BIT TOWARD THE HOLIDAY WEEKEND WITH A SERIES OF  
DISTURBANCES TRACKING ACROSS THE REGION, BUT STILL PLENTY OF  
TIME FOR THINGS TO EVOLVE AND CHANGE GIVEN THE MIDWEEK PATTERN.  
 
WAGNER  
 
 
   
AVIATION  
 
ISSUED 734 PM CDT SUN JUN 28 2026  
 
AREAS OF MVFR CIGS CAN BE EXPECTED TNT AS A WARM FRONT  
APPROACHES FROM THE SOUTHWEST. SCATTERED THUNDERSTORMS WILL  
CONTINUE AT TIMES TNT TOWARD CENTRAL WI BUT LESS LIKELY FROM  
MADISON TO MILWAUKEE AND SWD. THE MVFR CIGS WILL THEN DISSIPATE  
SHORTLY AFTER SUNRISE BUT COULD LINGER LONGER TOWARD EAST  
CENTRAL WI. VFR CONDITIONS WILL THEN PREVAIL THE REMAINDER OF  
MON-MON NT.  
 
GEHRING  
 
 
   
MARINE  
 
ISSUED 245 PM CDT SUN JUN 28 2026  
 
LOW PRESSURE OVER THE PLAINS CONTINUES TO DEEPEN AND SHIFT  
WINDS MORE SOUTHERLY ACROSS LAKE MICHIGAN TONIGHT INTO MONDAY.  
STRONGER WINDS AND BUILDS WAVES WILL RESULT IN SMALL CRAFT  
CONDITIONS TONIGHT FOR AREAS NORTH OF PORT WASHINGTON, WHILE  
CONDITIONS DEVELOPS MONDAY AFTERNOON FOR NEARSHORE SOUTH OF PORT  
WASHINGTON TO WINTHROP HARBOR. BREEZY SOUTHERLY WINDS WILL  
PERSIST THROUGH MIDWEEK AS THE BLOCKING HIGH OVER THE SOUTHEAST  
US BRINGS HOT AND HUMID CONDITIONS TO THE REGION. ADDITIONALLY  
WILL SEE DAILY THUNDERSTORM CHANCES RETURN FOR THE END OF HE  
WEEK INTO THE WEEKEND.  
 
WAGNER  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060...4 AM MONDAY TO 10 PM  
MONDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643...4 AM MONDAY TO 10 PM MONDAY.  
 
SMALL CRAFT ADVISORY...LMZ644-LMZ645-LMZ646...NOON MONDAY TO  
10 PM MONDAY.  
 
 
 
 
 
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