879  
FXUS63 KMKX 031509 AAA  
AFDMKX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
1009 AM CDT WED SEP 3 2025  
   
KEY MESSAGES  
 
- SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE INTO THE  
AFTERNOON HOURS.  
 
- CHILLY LOW TEMPERATURES TONIGHT, WITH BELOW-NORMAL  
TEMPERATURES CONTINUING INTO THIS WEEKEND.  
 
- ADDITIONAL SHOWERS AND ISOLATED STORMS LIKELY (~60-75+%  
CHANCES) THURSDAY NIGHT INTO EARLY FRIDAY MORNING.  
 
- HIGH TEMPERATURES SLOWLY WARM BACK UP EARLY NEXT WEEK.  
 
 
   
UPDATE  
 
ISSUED 1009 AM CDT WED SEP 3 2025  
 
THE BACK EDGE OF THE SHOWERS ASSOCIATED WITH A COLD FRONT HAS  
MOVED INTO THE NORTHWEST FORECAST AREA AND WILL CONTINUE TO  
PROGRESS SOUTHEASTWARD THROUGH LATE MORNING / EARLY AFTERNOON.  
COULD SEE SOME ISOLATED THUNDER AS THE SHOWERS MOVE THROUGH.  
SHOULD SEE A FEW BREAKS IN THE CLOUDS BEHIND THE SHOWERS/FRONT  
THIS AFTERNOON ALONG WITH BREEZY NORTHWEST WINDS. IN ALL, THE  
FORECAST LOOKS ON TRACK THROUGH THE REST OF THE AFTERNOON.  
 
DDV  
 
 
   
SHORT TERM  
 
ISSUED 351 AM CDT WED SEP 3 2025  
 
TODAY AND TONIGHT:  
 
SYNOPSIS/MESOANALYSIS: SURFACE CYCLOGENESIS IS ONGOING OVER NORTHERN  
LAKE SUPERIOR EARLY THIS MORNING, WITH 3 AM SURFACE OBSERVATIONS  
PLACING THE DEVELOPING AREA OF LOW PRESSURE JUST TO THE EAST OF ISLE  
ROYALE. A COLD FRONT EXTENDS SOUTHWEST FROM THE LOW, WITH  
OBSERVATIONS PLACING THE BOUNDARY ALONG AN APPROXIMATE BAYFIELD TO  
MINNEAPOLIS AXIS AS OF 3 AM. AHEAD OF THE FRONT, MODEL ANALYSIS &  
THE MKX VWP HAVE SHOWN STEADILY INCREASING WINDS IN THE 925-700 MB  
LAYER, WITH WEAK WARM ADVECTION TRIGGERING THE ONGOING AREAS OF  
SHOWERS FROM JANESVILLE NORTH TO MARKESAN. OCCASIONAL LIGHTNING HAS  
BEEN NOTED WITHIN THE SHOWER ACTIVITY, THANKS TO WEAK (~250-500  
J/KG) MUCAPE IN PLACE ACROSS THE REGION. SAID AREAS OF SHOWERS &  
ISOLATED STORMS WILL CONTINUE TO MOVE EAST-SOUTHEAST THROUGH  
DAYBREAK, WITH ADDITIONAL SHOWER AND ISOLATED STORM DEVELOPMENT  
ANTICIPATED THIS MORNING & AFTERNOON AS THE COLD FRONT MOVES IN FROM  
THE NORTH. APART FROM QUICK HEAVY DOWNPOURS AND A FEW LIGHTNING  
STRIKES, HAZARDOUS WEATHER IS NOT ANTICIPATED IN THIS ACTIVITY.  
CONDITIONS WILL DRY OUT THIS EVENING AS WINDS TURN NORTHWESTERLY &  
USHER A DRIER AIR MASS INTO THE REGION. SAID NORTHWEST WINDS WILL  
ALSO PULL A MUCH COOLER CANADIAN AIR MASS INTO SOUTHERN WISCONSIN,  
WITH CHILLY LOW TEMPERATURES ANTICIPATED FRIDAY MORNING.  
 
REST OF OVERNIGHT THROUGH TODAY: SHOWERS AND ISOLATED STORMS WILL  
INCREASE IN COVERAGE THIS MORNING, LASTING INTO THE AFTERNOON HOURS.  
PRECIPITABLE WATER VALUES OF 1-1.5 INCHES WILL SUPPORT BRIEF HEAVY  
DOWNPOURS---ESPECIALLY IN EMBEDDED STORMS---THOUGH FAST SHOWER/STORM  
MOTIONS WILL KEEP HYDRO CONCERNS MINIMAL. EXPECT 0.1-0.25" RAINFALL  
TOTALS TO BE THE NORM ACROSS THE MAJORITY OF THE REGION, WITH  
EMBEDDED POCKETS OF HIGHER (~0.5-0.75"+) TOTALS WHERE EMBEDDED  
THUNDERSTORMS TRACK. DON'T ANTICIPATE ANY SEVERE WEATHER HAZARDS IN  
TODAY'S ACTIVITY, BUT WILL BE MONITORING FOR AN ISOLATED STRONGER  
WIND GUST (~30-40 MPH) IN EMBEDDED STORMS GIVEN DYNAMIC WIND FIELDS  
AT THE 850 MB LEVEL. GRAB AN UMBRELLA OR JACKET BEFORE HEADING OUT  
THE DOOR THIS MORNING.  
 
TONIGHT: THE ARRIVING MUCH COOLER CANADIAN AIR MASS WILL RESULT IN  
CHILLY OVERNIGHT LOWS, PARTICULARLY AWAY FROM THE IMMEDIATE LAKE  
MICHIGAN SHORELINE. ANTICIPATE WIDESPREAD TEMPS IN THE LOWER 40S,  
WITH POCKETS OF UPPER 30S READINGS POSSIBLE IN LOW-LYING SPOTS.  
WHILE WELL BELOW EARLY SEPTEMBER NORMALS, THESE READINGS WILL LIKELY  
FALL A TOUCH SHORT OF RECORD LEVELS (41 IN MILWAUKEE; 35 IN  
MADISON). NORTHWEST WINDS WILL TAPER AS THE NIGHT PROGRESSES, BUT  
WILL REMAIN JUST ELEVATED ENOUGH TO SUPPORT FEEL-LIKE TEMPS IN THE  
MID-UPPER 30S NORTH & WEST OF MILWAUKEE. BE SURE TO GRAB A LIGHT  
JACKET IF HEADING OUTDOORS LATE TONIGHT/EARLY THURSDAY MORNING.  
 
QUIGLEY  
 
 
   
LONG TERM  
 
ISSUED 351 AM CDT WED SEP 3 2025  
 
THURSDAY THROUGH TUESDAY:  
 
WESTERLY WINDS CONTINUE ON THURSDAY AS THE OCCLUDED LOW CONTINUES TO  
SPIN IN NORTHERN ONTARIO, WITH TEMPERATURES IN THE MID-60S EXPECTED  
ACROSS SOUTHERN WISCONSIN. A CLIPPER SYSTEM DEVELOPS IN THE NORTHERN  
CANADIAN PRAIRIES AND SWINGS SOUTHEASTWARD QUICKLY ALONG THE  
SOUTHERN EDGES OF THE UPPER LEVEL LOW, BRINGING IN A QUICK COLD  
FRONT AND ASSOCIATED PRECIPITATION (60-80% CHANCES) THURSDAY NIGHT  
INTO FRIDAY MORNING. WITH LOW TEMPERATURES AROUND 50 DEGREES  
THURSDAY NIGHT AND MINIMAL INSTABILITY, NOT EXPECTING LIGHTNING WITH  
THIS ACTIVITY. WATERSPOUTS MAY BE POSSIBLE BEHIND THE COLD FRONT, AS  
THE CLIPPER DOES LOOK TO PROGRESS THROUGH THE MIDDLE OF LAKE  
MICHIGAN.  
 
AS THE CLIPPER EXITS TO THE NORTHWEST ALONG THE UPPER LEVEL LOW, IT  
BECOMES ABSORBED INTO THE CENTER OF THE OCCLUDED LOW IN ONTARIO INTO  
SATURDAY. A FEW WRAP-AROUND SHOWERS ARE POSSIBLE FRIDAY, BUT CHANCES  
REMAIN LOW AT THIS TIME (~10% CHANCE). EXPECT WEST- NORTHWESTERLY  
FLOW TO BRING HIGHS IN THE LOW 60S AND LOWS IN THE LOW 40S FRIDAY  
AND SATURDAY. THE COMBINED LOW THEN PROPAGATES EASTWARD AS HIGH  
PRESSURE RETURNS TO THE WESTERN GREAT LAKES SATURDAY NIGHT INTO  
SUNDAY, ALLOWING TEMPERATURES TO CLIMB BACK TO NEAR 70 DEGREES  
SUNDAY AND MONDAY.  
 
TUESDAY, EXPECT SOUTHERLY FLOW TO RETURN TO THE REGION AS LOW  
PRESSURE DEVELOPS IN THE NORTHERN PLAINS, BRINGING TEMPERATURES IN  
THE LOW 70S AND POTENTIAL FOR SHOWERS (15-25% CHANCE) ALONG A WARM  
FRONTAL FEATURE DEVELOPING OVER WISCONSIN.  
 
MH  
 
 
   
AVIATION  
 
ISSUED 1009 AM CDT WED SEP 3 2025  
 
THE BACK EDGE OF THE SHOWERS ASSOCIATED WITH A COLD FRONT HAS  
MOVED INTO THE NORTHWEST FORECAST AREA AND WILL CONTINUE TO  
PROGRESS SOUTHEASTWARD THROUGH LATE MORNING / EARLY AFTERNOON.  
COULD SEE SOME ISOLATED THUNDER AS THE SHOWERS MOVE THROUGH. IFR  
TO MVFR CEILINGS WILL PERSIST INTO AT LEAST EARLY AFTERNOON.  
SHOULD SEE A FEW BREAKS IN THE CLOUDS BEHIND THE SHOWERS/FRONT  
THIS AFTERNOON ALONG WITH BREEZY NORTHWEST WINDS. CLOUDS BASES  
MAY RAISE TO VFR BY MID/LATE AFTERNOON, WITH DECREASING SKIES  
EXPECTED THIS EVENING AND OVERNIGHT.  
 
DDV  
 
 
   
MARINE  
 
ISSUED 351 AM CDT WED SEP 3 2025  
 
1002 MB LOW PRESSURE IS CENTERED OVER LAKE SUPERIOR THIS MORNING,  
RESULTING IN BREEZY SOUTHWEST WINDS ACROSS THE OPEN WATERS OF LAKE  
MICHIGAN. SAID LOW WILL PROGRESS TOWARD THE ONTARIO-QUEBEC BORDER  
TODAY, DEEPENING TO NEAR 996 MB IN THE PROCESS. BREEZY SOUTHWEST  
WINDS WILL THUS CONTINUE INTO THIS MORNING, WITH GUSTS IN THE 20-25  
KNOT RANGE ANTICIPATED ACROSS ALL OF LAKE MICHIGAN. A FEW GUSTS  
COULD BRIEFLY GALE-FORCE, PARTICULARLY ACROSS THE NORTHERN THIRD OF  
THE WATERS. WINDS WILL QUICKLY SHIFT OUT OF THE NORTHWEST THIS  
AFTERNOON AND EVENING AS A COLD FRONT MOVES ACROSS THE WATERS.  
ADDITIONAL GUSTS IN THE 20-25 KNOT RANGE ARE ANTICIPATED DURING AND  
IMMEDIATELY FOLLOWING THE FRONTAL PASSAGE. WINDS WILL TAPER TONIGHT  
AS 1012 MB HIGH PRESSURE SETTLES INTO THE NORTHERN GREAT PLAINS.  
 
HIGH PRESSURE WILL PROGRESS EAST INTO THE WESTERN OHIO RIVER VALLEY  
ON THURSDAY, ALLOWING WINDS TO TURN OUT OF THE SOUTHWEST BY THE  
EARLY AFTERNOON HOURS. WINDS WILL QUICKLY BECOME GUSTY THURSDAY  
EVENING INTO PREDAWN FRIDAY MORNING AS A SECOND AREA OF 1000 MB LOW  
PRESSURE APPROACHES LAKE MICHIGAN FROM THE NORTHERN GREAT PLAINS.  
THE LOW WILL CROSS THE WATERS NEAR/JUST AFTER DAYBREAK FRIDAY  
MORNING, RESULTING IN A WEST-NORTHWEST WIND SHIFT FROM LATE MORNING  
INTO THE EARLY AFTERNOON. GALE FORCE GUSTS ARE EXPECTED OVER AT  
LEAST THE SOUTHERN HALF OF LAKE MICHIGAN AS THE LOW APPROACHES AND  
CROSSES EARLY FRIDAY MORNING. HEADLINES WILL BECOME NECESSARY IN  
SUBSEQUENT FORECASTS. GUSTS WILL BEGIN TO TAPER FRIDAY AFTERNOON AND  
EVENING AS THE AFOREMENTIONED LOW MOVES INTO QUEBEC.  
 
SHOWERS AND ISOLATED THUNDERSTORMS ARE LIKELY THIS MORNING AND  
AFTERNOON AS A COLD FRONT MOVES SOUTH ACROSS LAKE MICHIGAN. SEVERE  
WEATHER IS NOT EXPECTED, THOUGH A FEW STORMS COULD PRODUCE BRIEF  
GUSTY WINDS. A FEW WATERSPOUTS ARE POSSIBLE IN EMBEDDED  
THUNDERSTORMS, PARTICULARLY ACROSS THE NORTHERN HALF OF LAKE  
MICHIGAN. SCATTERED LAKE EFFECT SHOWERS WILL REMAIN POSSIBLE THROUGH  
THE DAY ON THURSDAY OVER FAR NORTHERN LAKE MICHIGAN. ADDITIONAL  
ISOLATED WATERSPOUTS ARE POSSIBLE IN THIS ACTIVITY. SHOWERS AND  
ISOLATED THUNDERSTORMS ARE LIKELY EARLY FRIDAY MORNING AHEAD OF THE  
APPROACHING SECOND AREA OF LOW PRESSURE.  
 
NORTHWEST WINDS WILL BECOME GUSTY IN NEARSHORE ZONES LATE THIS  
AFTERNOON THROUGH THE FIRST PART OF THIS EVENING BEHIND THE  
DEPARTING COLD FRONT. A FEW GUSTS COULD BRIEFLY APPROACH SMALL CRAFT  
ADVISORY THRESHOLDS, PARTICULARLY BETWEEN 7 PM - 1 AM CDT. GIVEN THE  
EXPECTED BRIEF AND ISOLATED NATURE OF ANY SUCH GUSTS, SMALL CRAFT  
ADVISORIES AREN'T ANTICIPATED AT THIS TIME. PERIODS OF SHOWERS AND  
EMBEDDED THUNDERSTORMS WILL ALSO ACCOMPANY THE APPROACHING/PASSING  
COLD FRONT, WITH THE BEST CHANCES BEING THIS MORNING AND AFTERNOON.  
SOUTHWEST WINDS QUICKLY BECOME GUSTY THURSDAY NIGHT AHEAD OF A  
SECOND AREA OF APPROACHING LOW PRESSURE, ULTIMATELY SHIFTING OUT OF  
THE WEST-NORTHWEST BY SUNRISE FRIDAY AS THE LOW DEPARTS TO THE EAST.  
WIDESPREAD GUSTS AT AND ABOVE SMALL CRAFT ADVISORY LEVELS ARE  
EXPECTED DURING THIS TIME FRAME, WITH A FEW GUSTS APPROACHING GALE  
FORCE DURING THE PREDAWN HOURS FRIDAY. SMALL CRAFT ADVISORIES WILL  
BECOME NECESSARY IN SUBSEQUENT FORECASTS.  
 
QUIGLEY  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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