571  
FXUS63 KMKX 310504  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
1204 AM CDT MON AUG 31 2026  
   
KEY MESSAGES  
 
- HEAT & HUMIDITY CONTINUES THROUGH AT LEAST MID-WEEK. AFTERNOON  
HEAT INDICES IN THE LOW-MID 90S EXPECTED EACH DAY, WITH UPPER  
90S TO NEAR TRIPLE DIGITS POSSIBLE IN AREAS EXPERIENCING MORE  
SUNSHINE.  
 
- SLIGHT CHANCES (~15-30%) FOR AFTERNOON STORMS MONDAY AND  
TUESDAY. AN ISOLATED SEVERE STORM WITH HAIL OR GUSTY WINDS  
CAN'T BE RULED OUT IF DEVELOPMENT OCCURS.  
 
- PERIODS OF OFF/ON SHOWERS AND STORMS LINGER THROUGH THE SECOND  
HALF OF THE WEEK.  
 
 
   
SHORT TERM  
 
ISSUED 1210 AM CDT MON AUG 31 2026  
 
CURRENT OVERNIGHT THROUGH TUESDAY NIGHT:  
 
SYNOPSIS/MESOANALYSIS: A BROKEN BAND OF SHOWERS CONTINUES TO MARCH  
EAST ACROSS THE AREA LATE THIS EVENING. INITIALLY TRIGGERED BY LOW  
LEVEL WARM ADVECTION OVER IOWA, ACTIVITY HAS STEADILY WANED WITH  
EASTWARD EXTENT AS IT MOVES OFF THE CORE OF THE LOW LEVEL JET. COULD  
STILL NEVERTHELESS SEE SOME SCATTERED SHOWERS CONTINUE EAST ALL THE  
WAY TO THE LAKE MICHIGAN SHORELINE THROUGH 1 AM, WITH HAZARDS NOT  
ANTICIPATED. CURRENTLY MOVING THROUGH THE DAKOTAS, A COLD FRONT WILL  
VERY SLOWLY APPROACH FROM THE NORTHWEST THROUGH MONDAY NIGHT, LIKELY  
STALLING NEAR OR JUST NORTH OF THE AREA BY TUESDAY. THE BOUNDARY'S  
SLOW PROGRESSION WILL KEEP SOUTHERN WISCONSIN ENTRENCHED WITHIN A  
WARM AND HUMID WARM SECTOR THROUGH THE DURATION OF THE PERIOD, WITH  
AFTERNOON HEAT INDICES IN AT LEAST THE LOW-MID 90S ANTICIPATED.  
UPPER 90S HEAT INDICES ARE POSSIBLE IN LOCATIONS EXPERIENCING BREAKS  
IN CLOUD COVER. OFF & ON THUNDERSTORM CHANCES WILL REMAIN A  
CONSISTENT PART OF THE FORECAST PICTURE, PARTICULARLY IN THE  
VICINITY OF THE LOW LEVEL JET DURING OVERNIGHT PERIODS. CAPPING &  
NEBULOUS SYNOPTIC FORCING AWAY FROM THE FRONT LEAVES THE COVERAGE &  
LOCATION OF ANY DAYTIME STORM DEVELOPMENT UNCERTAIN, WITH TRENDS  
NEEDING TO BE MONITORED. IN THE EVENT ANY DAYTIME DEVELOPMENT  
OCCURS, AN ISOLATED STRONGER STORM WITH HAIL OR GUSTY WINDS WOULD BE  
POSSIBLE.  
 
REST OF OVERNIGHT: WILL BE WATCHING FOR AREAS FOG DEVELOPMENT,  
PARTICULARLY ACROSS THE WEST WHERE PRECIP HAS ENDED AND BREAKS IN  
THE CLOUDS HAVE MATERIALIZED. NOT CURRENTLY EXPECTING A DENSE FOG  
THREAT GIVEN VARIABILITY TO WINDS AND SKY COVER, BUT WILL KEEPING  
TABS ON VIS TRENDS. ANTICIPATING ANOTHER SCATTERING OF LLJ-  
AFFILIATED STORM DEVELOPMENT DURING THE PREDAWN HOURS, WITH GREATEST  
POTENTIAL ACROSS THE EAST WHERE 850-700 MB LAYER TEMPERATURES WILL  
REMAIN A TOUCH COOLER. NOT EXPECTING ANY SEVERE HAZARDS IN THIS  
ACTIVITY.  
 
MONDAY AFTERNOON & TUESDAY AFTERNOON: WITH PROLONGED PERIODS OF DRY  
CONDITIONS FORECAST, WILL BE WATCHING HEAT INDEX TRENDS CLOSELY, AS  
A WARM AND VERY HUMID AIR MASS WILL BE SUPPORTIVE FOR 90+ DEGREE  
READINGS. CURRENT FORECAST SHOWS READINGS IN AT LEAST THE LOW-MID  
90S, WITH UPPER 90S READINGS OCCURRING IN AREAS EXPERIENCING GREATER  
SUNSHINE. SHOULD ANY UPWARD TRENDS OCCUR, MAY NEED TO CONSIDER  
POSSIBLE HEAT ADVISORIES ACROSS PARTS OF THE AREA EACH DAY. WILL  
CONTINUE TO PROVIDE UPDATES. THE WARM/HUMID AIR MASS WILL ALSO BE  
RIPE FOR STORM DEVELOPMENT, THOUGH AN ABSENCE OF LARGER-SCALE  
TRIGGERS MAKES DAYTIME STORM DEVELOPMENT UNCERTAIN. SMALLER SCALE  
FEATURES SUCH AS MCV'S AND OUTFLOW BOUNDARIES WILL THUS PLAY A LARGE  
PART IN EACH DAY'S STORM POTENTIAL. HAVE KEPT PRECIP PROBABILITIES  
ON THE LOW (~30% OR LESS) END DURING EACH AFTERNOON PERIOD GIVEN THE  
UNCERTAINTY. WILL BE MONITORING THE EVOLUTION OF ONGOING CONVECTION  
IN THE CENTRAL PLAINS, AS ANY RESULTANT MCV'S WOULD BE POISED TO  
TRACK FAVORABLY ACROSS SOUTHERN WISCONSIN ~2-8 PM MONDAY  
AFTERNOON/EVENING (& ACT TO ENHANCE PRECIP POTENTIAL). LATER  
FORECASTS WILL EVALUATE THESE TRENDS & UPDATE PRECIP PROBS IF  
NECESSARY.  
 
QUIGLEY  
 
 
   
LONG TERM  
 
ISSUED 1210 AM CDT MON AUG 31 2026  
 
TUESDAY NIGHT THROUGH SUNDAY:  
 
SYNOPSIS: THE SLOW-MOVING COLD FRONT APPROACHING DURING THE SHORT  
TERM PERIOD WILL CONTINUE INTO THE AREA ON WEDNESDAY, WITH GLOBAL  
FORECAST GUIDANCE BEGINNING TO HINT AT ITS NORTHWARD RETURN AS A  
WARM FRONT THROUGH THE SECOND HALF OF THE WORK WEEK. ABOVE NORMAL  
TEMPERATURES AND MUGGY CONDITIONS ARE THUS BECOMING FAVORED INTO  
NEXT WEEKEND, THOUGH IT REMAINS UNCERTAIN IF THE COMBINED HEAT AND  
HUMIDITY WILL REACH THE VERY UNCOMFORTABLE LEVELS ANTICIPATED DURING  
THE SHORT TERM PERIOD. THIS WILL BE A TREND TO MONITOR OVER COMING  
FORECASTS. GIVEN THE LINGERING SURFACE FRONT & STILL WARM/MUGGY  
CONDITIONS, ADDITIONAL PERIODS OF SHOWERS AND STORMS ARE ANTICIPATED  
THROUGH AT LEAST THE BEGINNING OF NEXT WEEKEND. WHETHER OR NOT ANY  
STORMS COULD BE STRONG/SEVERE REMAINS UNCERTAIN, WITH TRENDS BEING  
MONITORED THROUGH THE FIRST HALF OF THIS WEEK. WHILE NOT YET  
CONCLUSIVE ACROSS ALL GLOBAL GUIDANCE, SOME SOLUTIONS HINT THAT  
BUILDING HIGH PRESSURE OVER THE QUEBEC-ONTARIO VICINITY COULD BEGIN  
USHERING IN DRIER AIR BY THE SECOND HALF OF NEXT WEEKEND. IF THESE  
SIGNALS WERE TO VERIFY, A MORE SEASONABLE PATTERN CHANGE WOULD BE IN  
STORE FOR SUNDAY & JUST BEYOND THE CURRENT LONG TERM PERIOD.  
 
QUIGLEY  
 
 
   
AVIATION  
 
ISSUED 1210 AM CDT MON AUG 31 2026  
 
MAINLY VFR FLIGHT CATEGORIES PREVAIL THROUGH THE PERIOD AT ALL  
TERMINALS. BROKEN BAND OF -RA CONTINUES TO PROGRESS EAST TOWARD LAKE  
MICHIGAN LATE THIS EVENING. WHILE PRECIP HAS WANED IN INTENSITY,  
SCATTERED UPSTREAM RA OBSERVATIONS HAVE MOTIVATED TEMPO GROUPS  
THROUGH ~07Z AT ALL LAKE MICHIGAN TERMINALS. EXPECT ACTIVITY TO MOVE  
OFFSHORE THEREAFTER. NOT ANTICIPATING ANY CATEGORICAL REDUCTIONS  
GIVEN THE NOTED DECREASES IN INTENSITY. WILL BE MONITORING FOR  
ADDITIONAL RA DEVELOPMENT THROUGH THE OVERNIGHT AS THE LOW LEVEL JET  
INCREASES REGIONALLY, PARTICULARLY NEAR LAKE MICHIGAN, WHERE PROB30  
GROUPS WILL BE INTRODUCED IN THE UPCOMING 06Z FORECAST. LLWS  
POTENTIAL WILL ACCOMPANY THE LOW LEVEL JET, WITH MENTIONS CONTINUING  
AT ALL AERODROMES. CAN'T RULE OUT SCATTERED -SHRA/-TSRA DEVELOPMENT  
MONDAY AFTERNOON, THOUGH CONFIDENCE IS TOO LOW TO JUSTIFY ANY  
MENTIONS AT THIS TIME.  
 
QUIGLEY  
 
 
   
MARINE  
 
ISSUED 1210 AM CDT MON AUG 31 2026  
 
A WARM FRONT IS DRAPED OVER CENTRAL LAKE MICHIGAN THIS EVENING,  
RESULTING IN GENERALLY SOUTHERLY WINDS ACROSS THE SOUTHERN HALF OF  
THE WATERS WITH NORTHEASTERLY BREEZES FURTHER NORTH. THE BOUNDARY  
WILL ATTEMPT TO WORK NORTHWARD FROM THE REMAINDER OF THE OVERNIGHT  
THROUGH MONDAY, BRINGING A BREEZY SOUTH-SOUTHWEST WIND SHIFT IN ITS  
WAKE. AREAS REMAINING NORTH OF THE FRONT WILL CONTINUE TO SEE EAST-  
NORTHEAST WINDS. SIMILAR TO TODAY, SOUTH-SOUTHWEST WINDS WILL BECOME  
BREEZY ONCE AGAIN ON MONDAY AFTERNOON, WHEN 25-30 KNOT GUSTS ARE  
ANTICIPATED OVER AT LEAST THE SOUTHERN TWO-THIRDS OF THE WATERS.  
GALES ARE NOT ANTICIPATED. PERIODS OF SHOWERS AND STORMS CONTINUE  
THROUGH THE OVERNIGHT HOURS TONIGHT, WITH SEVERE WEATHER NOT  
ANTICIPATED.  
 
998 MB LOW PRESSURE WILL SHIFT FROM THE CANADIAN GREAT PLAINS INTO  
ONTARIO MONDAY NIGHT THROUGH TUESDAY, ULTIMATELY REACHING THE  
SOUTHERN SHORES OF THE HUDSON BAY BY DAYBREAK WEDNESDAY. THE  
ADVANCING LOW WILL PULL A SLOW-MOVING COLD FRONT OVER LAKE MICHIGAN  
IN THE PROCESS, WITH NORTH-NORTHEAST WINDS ESTABLISHING IN THE WAKE  
OF THE BOUNDARY. WHETHER THE FRONT CLEARS ENTIRELY SOUTH OF THE  
WATERS OR STALLS OUT SOMEWHERE OVER THE LAKE REMAINS UNCERTAIN. WITH  
THE FRONT IN THE VICINITY, SHOWER AND STORM CHANCES THUS CONTINUE  
MONDAY NIGHT THROUGH AT LEAST MID-WEEK. A FEW STRONGER STORMS WITH  
GUSTY WINDS AND HAIL ARE POSSIBLE DURING THIS TIME FRAME. IF THE  
FRONT REMAINS CLOSE TO STATIONARY THROUGH THE FIRST HALF OF THE  
WEEK, IT WILL ULTIMATELY CLEAR SOUTH OF LAKE MICHIGAN BY THURSDAY,  
BRINGING NORTHEAST WINDS FOR THE END OF THE WEEK.  
 
SMALL CRAFT ADVISORY CONDITIONS HAVE TAPERED THIS EVENING IN  
NEARSHORE ZONES. BREEZY SOUTH-SOUTHWEST WINDS ARE EXPECTED ONCE  
AGAIN ON MONDAY, WHEN GUSTS TO OR SLIGHTLY ABOVE 20 KNOTS ARE  
FORECAST. A FEW GUSTS COULD BRIEFLY APPROACH 25 KNOTS, BUT AREN'T  
EXPECTED TO BE WIDESPREAD ENOUGH TO WARRANT SMALL CRAFT ADVISORIES  
AT THIS TIME. WILL NEVERTHELESS BE MONITORING TRENDS. SHOWER AND  
STORM CHANCES CONTINUE FROM THE REMAINDER OF THE OVERNIGHT THROUGH  
AT LEAST MID-WEEK. A FEW STRONGER STORMS WITH GUSTY WINDS AND HAIL  
ARE POSSIBLE DURING THE AFTERNOON/EVENING HOURS ON MONDAY AND  
TUESDAY.  
 
QUIGLEY  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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