280  
FXUS63 KMKX 291157  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
657 AM CDT MON JUN 29 2026  
   
KEY MESSAGES  
 
- EXTREME HEAT WARNING IN EFFECT FOR ALL OF SOUTHERN WI NOON  
TODAY THROUGH TUESDAY EVENING. ADDITIONAL HEAT HEADLINES WILL  
LIKELY BE NEEDED FOR THE MIDDLE TO LATE PORTIONS OF THE WEEK  
AS THIS PROLONGED HEATWAVE CONTINUES.  
 
- ISOLATED SHOWERS AND STORMS 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 TODAY, WITH MODERATE SWIM RISK CONDITIONS FOR  
MILWAUKEE AND RACINE COUNTIES.  
 
 
   
UPDATE  
 
ISSUED 657 AM CDT MON JUN 29 2026  
 
DEWPOINTS OF 72 TO 76 DEGREES HAVE ADVECTED IN OVERNIGHT, WITH  
STRONG WARM AND MOIST ADVECTION CONTINUING THROUGH TODAY.  
EXPECTING HEAT INDEX VALUES TO EASILY REACH EXTREME HEAT WARNING  
CRITERIA. WITH SUCH HIGH DEWPOINTS, ALSO NOT ANTICIPATING  
TEMPERATURES TO FALL BELOW 75 DEGREES TONIGHT. HIGH SWIM RISK  
CONDITIONS ARE EXPECTED FOR OZAUKEE AND SHEBOYGAN COUNTY LAKE  
MICHIGAN BEACHES THROUGH 10 PM CDT, WITH MODERATE SWIM RISK  
CONDITIONS FOR MILWAUKEE AND RACINE COUNTIES. STAY OUT OF THE  
WATER IF IN A HIGH SWIM RISK AREA. AVOID DANGEROUS AREAS SUCH AS  
PIERS AND BREAKWALLS!  
 
MH  
 
 
   
SHORT TERM  
 
ISSUED 1044 PM CDT SUN JUN 28 2026  
 
TONIGHT THROUGH TUESDAY:  
 
THE NOSE OF A SLY LOW LEVEL JET AROUND 35-40 KT WILL REMAIN OVER  
NRN AND CENTRAL WI TNT. THUS NEW ELEVATED SHOWERS AND STORMS  
WILL DEVELOP OVER THIS REGION DUE TO THE LOW TO MID LEVEL WARM,  
MOIST ADVECTION AND EMBEDDED FRONTOGENESIS. 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  
 
 
   
LONG TERM  
 
ISSUED 1044 PM CDT SUN JUN 28 2026  
 
TUESDAY NIGHT THROUGH SUNDAY:  
 
THE HEATWAVE WILL CONTINUE MUCH OF THE WEEK. THE STRONG UPPER  
RIDGE AXIS WILL GRADUALLY SHIFT TO THE EAST AND SOUTH BECOMING A  
WEST TO EAST UPPER RIDGE FROM THE ERN OHIO VALLEY TO THE ERN  
SEABOARD BY WED, AND LASTING THROUGH THE WEEK WITH ONLY MINOR  
WEAKENING. MEANWHILE A SERIES OF SHORTWAVE TROUGHS WILL CONTINUE  
TO TRAVERSE FROM THE WRN USA INTO THE UPPER MS RIVER VALLEY AND  
NRN GREAT LAKES. THUS THE STORM TRACK WILL MAINLY REMAIN TO THE  
WEST AND NORTH OF SRN WI THROUGH THU WITH 500 MB HEIGHTS AT 588  
DM OR GREATER. THIS CONTINUES TO PLACE A HOT AND HUMID AIRMASS  
OVER SRN WI THROUGH THE WEEK. EXTREME HEAT WARNINGS OR HEAT  
ADVISORIES WILL LIKELY BE NEEDED MUCH OF THE WEEK. ONLY 20-40  
PERCENT CHANCES FOR SHOWERS AND STORMS TOWARD CENTRAL WI FOR TUE  
NT-WED NT WITH CHANCES INCREASING A BIT FOR LATE IN THE WEEK  
AND WEEKEND AS SHORTWAVE TROUGHS ARRIVE IN WLY FLOW ALOFT.  
 
GEHRING  
 
 
   
AVIATION  
 
ISSUED 657 AM CDT MON JUN 29 2026  
 
A FEW PATCHES OF FUEL ALTERNATIVE CEILINGS HAVE DEVELOPED  
ACROSS SOUTH-CENTRAL TO SOUTHWESTERN WISCONSIN THIS MORNING.  
THESE ARE EXPECTED TO LIFT AND SCATTER OUT WITHIN THE NEXT  
COUPLE HOURS. AFTER CLOUDS LIFT AND SCATTER, EXPECTING VFR  
CONDITIONS TO PREVAIL THROUGHOUT THE TAF PERIOD. GUSTY  
SOUTH-SOUTHEASTERLY WINDS OF 20-25 KT STARTING MIDDAY AND  
CONTINUING INTO THIS EVENING. OVERNIGHT, EXPECT WIND GUSTS TO  
DIMINISH BUT LLWS TO DEVELOP. WINDS WILL SHIFT TO SOUTHWESTERLY  
OVERNIGHT, BECOMING GUSTY AROUND 20 KT AGAIN TUESDAY MORNING.  
 
MH  
 
 
   
MARINE  
 
ISSUED 1044 PM CDT SUN JUN 28 2026  
 
LOW PRESSURE AROUND 29.2 INCHES IN EASTERN COLORADO WILL TRACK TO  
EASTERN NORTH DAKOTA BY MONDAY AFTERNOON. ITS WARM FRONT WILL  
MOVE NORTH ACROSS LAKE MICHIGAN ON MONDAY. LIGHT TO MODEST  
EASTERLY WINDS THIS EVENING WILL BECOME BREEZY SOUTHEASTERLY  
WINDS LATE TONIGHT AND MONDAY MORNING OVER THE LAKE. BREEZY  
SOUTH WINDS WILL THEN PREVAIL FROM MONDAY AFTERNOON INTO THE  
MIDDLE OF THE WEEK. MODEST SOUTHERLY WINDS WILL THEN PREVAIL FOR  
THURSDAY INTO FRIDAY. AREAS OF DENSE FOG MAY DEVELOP AT TIMES  
THIS WEEK DUE TO A VERY HUMID AIRMASS FLOWING OVER THE  
RELATIVELY COOLER WATERS OF THE LAKE. SCATTERED THUNDERSTORMS  
ARE FORECAST ON MOST DAYS ESPECIALLY OVER THE NORTH HALF.  
 
GEHRING  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060 UNTIL 10 PM MONDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643 UNTIL 10 PM MONDAY.  
 
SMALL CRAFT ADVISORY...LMZ644-LMZ645-LMZ646...NOON MONDAY TO  
10 PM MONDAY.  
 
 
 
 
 
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