997  
FXUS63 KMKX 121154  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
654 AM CDT SAT SEP 12 2026  
   
KEY MESSAGES  
 
- A FEW SHOWERS ARE SLOWLY PROGRESSING EASTWARD THIS MORNING. AN  
ISOLATED BOLT OF LIGHTNING IS POSSIBLE BUT NOT LIKELY.  
 
- ACTIVE START TO NEXT WEEK, WITH MULTIPLE PERIODS OF SHOWERS  
AND THUNDERSTORMS EXPECTED MONDAY EVENING THROUGH AT LEAST  
TUESDAY. SOME STORMS COULD PRODUCE HEAVY RAINFALL AND SOME  
GUSTY WINDS.  
 
- GALES ARE POSSIBLE LATER MONDAY INTO TUESDAY ACROSS THE LAKE  
MICHIGAN OPEN WATERS. A SMALL CRAFT ADVISORY MAY EVENTUALLY BE  
NEEDED MONDAY INTO TUESDAY FOR THE NEARSHORE WATERS.  
 
 
   
UPDATE  
 
ISSUED 655 AM CDT SAT SEP 12 2026  
 
A FEW SHOWERS HAVE PERSISTED ACROSS SOUTHWESTERN WISCONSIN THIS  
MORNING, WITH AN ISOLATED BOLT OF LIGHTNING REMAINING POSSIBLE,  
BUT UNLIKELY. SHOWER WILL CONTINUE TO WEAKEN AS THEY MOVE  
EASTWARD, WITH ONLY BRIEF RAINFALL EXPECTED. SOUTHWESTERLY WINDS  
THIS MORNING WILL SHIFT TO NORTHWESTERLY THIS AFTERNOON INTO  
THIS EVENING AS A COLD FRONT MOVES THROUGH. EVEN WITH THIS COLD  
FRONT, THE LATE TIMEFRAME OF THE FRONTAL PASSAGE WILL ALLOW FOR  
HIGHS AROUND 80 DEGREES IN MUCH OF SOUTHERN WISCONSIN. NAM NEST  
STILL INDICATES SOME POTENTIAL FOR ISOLATED STORMS TO DEVELOP IN  
SOUTHEASTERN WISCONSIN DURING THE FRONTAL PASSAGE, BUT  
CONFIDENCE REMAINS LOW AS CAPPING REMAINS IN PLACE AND OTHER  
CAMS HAVE NOT JOINED IN THIS SOLUTION.  
 
MH  
 
 
   
SHORT TERM  
 
ISSUED 1248 AM CDT SAT SEP 12 2026  
 
TODAY THROUGH SUNDAY:  
 
A COLD FRONT WILL MOVE EAST TOWARD THE AREA OVERNIGHT, SHIFTING  
EAST THROUGH THE AREA ON SATURDAY. THERE IS A LINE OF SHOWERS  
AND SOME STORMS DEVELOPING AHEAD OF THE FRONT FROM NORTHWEST TO  
WEST CENTRAL WISCONSIN, PUSHING SLOWLY EASTWARD. THIS ACTIVITY  
MAY DEVELOP FURTHER TO THE SOUTHWEST OVER THE NEXT FEW HOURS, AS  
MOST OF THE INSTABILITY IS ALONG AND JUST AHEAD OF THE FRONT.  
 
FORECAST SOUNDINGS ARE SHOWING A LOT OF DRY AIR LINGERING IN  
THE LOW LEVELS (MAINLY BELOW 8000 FEET AGL) OVER THE FORECAST  
AREA OVERNIGHT INTO SATURDAY. THIS MAY LIMIT ANY SHOWERS OR  
SPRINKLES FROM REACHING THE GROUND, AND SHOULD ALSO LIMIT THE  
ADVANCE OF ANY CONVECTION. FOR NOW, WILL LEAVE SCATTERED  
SPRINKLES IN FAR WEST AND NORTHWEST PARTS OF THE AREA OVERNIGHT  
INTO EARLY MORNING, AS THE FRONTOGENESIS WITH THE FRONT WEAKENS  
AS IT SHIFTS EAST AND THERE IS LITTLE TO NO OTHER SUPPORT FOR  
UPWARD VERTICAL MOTION.  
 
THERE IS MEAN LAYER CAPE OVER 1200 TO 1800 J/KG THAT DEVELOPS  
LATER TODAY, HIGHEST IN FAR SOUTHEAST WISCONSIN, WITH DAYTIME  
HEATING. HOWEVER, FORECAST SOUNDINGS ARE GENERALLY CAPPED AND  
HAVE A FAIR AMOUNT OF WARM AIR IN THE 5000 TO 9000 FOOT AGL  
LAYER HELP KEEP THE CAPPING IN PLACE. THUS, WILL LEAVE THE  
FORECAST DRY FOR NOW FOR THE REST OF TODAY.  
 
THERE SHOULD BE SOME MIDDLE TO HIGH CLOUDS THAT MOVE THROUGH,  
WITH SOME DIURNAL CUMULUS CLOUDS THAT DEVELOPS LATER IN THE  
MORNING INTO THIS AFTERNOON. WINDS SHIFT FROM THE SOUTH TO THE  
WEST NORTHWEST BEHIND THE FRONT AS IT MOVES THROUGH. SOME GUSTS  
OF 15 TO 20 MPH MAY OCCUR AHEAD OF AND BEHIND THE FRONT. WARM  
HIGHS IN THE UPPER 70S NORTHWEST TO LOWER TO MIDDLE 80S  
SOUTHEAST ARE EXPECTED TODAY.  
 
HIGH PRESSURE SHOULD MOVE EAST SOUTHEAST INTO THE AREA LATER  
TONIGHT INTO SUNDAY, WITH NORTHWEST WINDS BRINGING COLD AIR  
ADVECTION AND SOMEWHAT COOLER TEMPERATURES AND DEW POINTS INTO  
THE AREA. LOWS SHOULD DROP INTO THE LOWER TO MIDDLE 50S OVER  
MOST OF THE AREA TONIGHT, WITH HIGHS SUNDAY IN THE MIDDLE 60S TO  
AROUND 70 DEGREES. SOME PASSING DIFFERENTIAL CVA MAY HELP BRING  
ISOLATED TO SCATTERED SHOWERS TO THE AREA SUNDAY AS WELL,  
THOUGH FORECAST SOUNDINGS ARE SHOWING ONLY A FEW HOURS WORTH OF  
GOOD SATURATION FOR THIS TO OCCUR. FOR NOW, KEPT 20 TO 30  
PERCENT CHANCES FOR SHOWERS AT TIMES ON SUNDAY.  
 
WOOD  
 
 
   
LONG TERM  
 
ISSUED 1248 AM CDT SAT SEP 12 2026  
 
SUNDAY NIGHT THROUGH FRIDAY:  
 
HIGH PRESSURE WILL MOVE EAST OF THE REGION SUNDAY NIGHT INTO  
MONDAY, WITH INCREASING SOUTHEAST WINDS ON THE BACKSIDE OF THE  
HIGH KEEPING DRY AIR IN THE LOWER PORTIONS OF THE AIR COLUMN.  
THIS MAY HELP SHUNT BACK ANY ADVANCING SHOWERS AND STORMS TO  
LATER MONDAY OR MORE LIKELY MONDAY EVENING. THUS, CHANCES FOR  
PRECIPITATION ARE NOW LOWER (BELOW 30 PERCENT) IN THE EASTERN  
PARTS OF THE AREA, AND MAY NEED TO BE LOWERED MORE IN THE WEST  
(CURRENTLY 40 TO 70 PERCENT) IN LATER FORECASTS, IF THIS DRY  
LOOK IN THE MODEL TRENDS CONTINUES. CHILLY LOWS IN THE 40S  
SUNDAY NIGHT SHOULD REBOUND INTO THE UPPER 60S TO AROUND 70  
DEGREES ON MONDAY.  
 
MODELS AND ENSEMBLES SUGGEST THAT THE MAIN AREA OF SHOWERS AND  
THUNDERSTORMS SHOULD MOVE INTO WESTERN PARTS OF THE AREA MONDAY  
EVENING AND ELSEWHERE LATER MONDAY NIGHT. THE LOW LEVEL JET FEED  
OF MOISTURE AND UPWARD VERTICAL MOTION, ALONG THE SURFACE WARM  
FRONT, SHOULD HELP BRING ROUNDS OF SHOWERS AND SOME STORMS TO  
THE AREA INTO AT LEAST TUESDAY MORNING. FORECAST SOUNDINGS ARE  
SHOWING MOIST ADIABATIC PROFILES WITH TALL SKINNY MEAN LAYER  
CAPE THAT IS MODEST AT BEST AND HIGH PRECIPITABLE WATER VALUES  
APPROACHING OR OVER 2.00 INCHES. GIVEN THIS SETUP, SOME TRAINING  
OF CONVECTION MAY BE POSSIBLE, AND LOCALLY HEAVY RAINFALL MAY  
OCCUR.  
 
THE DEEP LAYER (30 TO 40 KNOTS) BULK SHEAR VALUES ARE FAIRLY  
ROBUST, THOUGH THE POOR LAPSE RATES AND TALL SKINNY CAPE MAY  
FAVOR MORE HEAVY RAINFALL THAN STRONG TO SEVERE STORMS. COULD  
STILL SEE STRONGER STORMS WITH SOME GUSTY WINDS OCCUR IN THIS  
SETUP. WILL CONTINUE TO MESSAGE THE HEAVY RAINFALL AND PERHAPS  
SOME STRONGER STORMS LATER MONDAY INTO MONDAY NIGHT/TUESDAY.  
 
THERE IS MORE UNCERTAINTY IF ANOTHER ROUND OF SHOWERS AND  
STORMS WITH SOME HEAVY RAINFALL WOULD OCCUR LATER TUESDAY INTO  
WEDNESDAY. THE DETERMINISTIC MODELS ARE TRENDING FURTHER SOUTH  
OF THE AREA WITH THIS NEXT ROUND OF PRECIPITATION, AS HIGH  
PRESSURE TO THE NORTH SHUNTS THIS ACTIVITY SOUTHWARD. ENSEMBLES  
STILL HAVE A FAIRLY WET PERIOD DURING THIS TIME, THOUGH THEY MAY  
NOT HAVE CAUGHT ONTO THIS TREND YET. FOR NOW, WILL LEAVE HIGHER  
CHANCES (40 TO 70 PERCENT) FOR SHOWERS AND STORMS FOR TUESDAY  
INTO WEDNESDAY, BUT ADJUSTMENTS DOWNWARD MAY BE NEEDED IF THIS  
DRIER TREND CONTINUES.  
 
THE HIGH MAY LINGER THROUGH A GOOD PORTION OF THE REST OF NEXT  
WEEK, SO THIS DRIER TREND MAY LINGER AS WELL. ENSEMBLES SUGGEST  
TEMPERATURES MAY REMAIN NEAR OR A LITTLE BELOW SEASONAL NORMAL  
VALUES.  
 
WOOD  
 
 
   
AVIATION  
 
ISSUED 655 AM CDT SAT SEP 12 2026  
 
VFR CONDITIONS EXPECTED THROUGHOUT TODAY AND TONIGHT, WITH  
CEILINGS AROUND 5000 FT AS WEAK SHOWERS WORK EASTWARD THIS  
MORNING. SCATTERED CUMULUS AROUND 5000 FT REMAIN, WITH HIGH  
LEVEL CLOUDS EXPECTED TO MOVE IN THIS AFTERNOON ALONG THE COLD  
FRONT. ISOLATED STORMS ARE POSSIBLE ALONG THE COLD FRONT IN FAR  
SOUTHEASTERN WISCONSIN THIS AFTERNOON, BUT CONFIDENCE IS VERY  
LOW (~10%). AHEAD OF THE FRONT, EXPECT SOUTHWESTERLY WINDS  
GUSTING AROUND 20 KT. BEHIND THE FRONT, EXPECT NORTHWESTERLY  
WINDS WITH GUSTS UP TO 15 KT. CUMULUS ENDS AROUND SUNSET, WITH  
SKIES BECOMING MOSTLY CLEAR OVERNIGHT. NORTHWEST WINDS DIMINISH  
TO BECOME LIGHT AND VARIABLE. WINDS REMAIN NORTHWESTERLY AND  
BEGIN TO INCREASE AGAIN INTO SUNDAY MORNING.  
 
MH  
 
 
   
MARINE  
 
ISSUED 1248 AM CDT SAT SEP 12 2026  
 
SOUTHERLY WINDS WILL CONTINUE TO INCREASE OVERNIGHT, AS A COLD  
FRONT APPROACHES THE REGION FROM THE WEST. WINDS WILL SHIFT OUT  
OF THE WEST NORTHWEST TODAY, AS THE COLD FRONT MOVES ACROSS THE  
LAKE. EXPECTING WIND GUSTS TO REMAIN PRIMARILY IN THE 25 TO 30  
KNOT RANGE OVER THE OPEN WATERS, THOUGH A FEW GUSTS APPROACHING  
GALE FORCE MAY OCCUR IN FAR NORTHERN PORTIONS OF THE LAKE.  
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE AHEAD OF THE  
APPROACHING COLD FRONT, MAINLY OVER NORTHERN PORTIONS OF THE  
LAKE. WINDS WILL APPROACH SMALL CRAFT ADVISORY LEVELS THIS  
AFTERNOON NORTH OF PORT WASHINGTON.  
 
HIGH PRESSURE AROUND 30.2 INCHES WILL BUILD IN FROM THE  
NORTHERN GREAT PLAINS SUNDAY NIGHT INTO MONDAY, BRINGING  
DECREASING WINDS SATURDAY NIGHT THROUGH SUNDAY, AND WINDS  
GRADUALLY SHIFTING TO THE EAST AND SOUTHEAST AND INCREASING  
SUNDAY NIGHT INTO MONDAY. THE HIGH WILL MOVE EAST OF THE WATERS  
MONDAY AFTERNOON AND EVENING.  
 
WINDS WILL INCREASE FURTHER AND VEER SOUTH SOUTHWEST MONDAY  
NIGHT INTO TUESDAY, AS LOW PRESSURE AROUND 29.4 INCHES DEVELOPS  
OVER MANITOBA. GALES CONTINUE TO APPEAR LIKELY DURING THIS TIME  
FRAME, WITH HEADLINES BECOMING NECESSARY IN LATER FORECASTS IF  
TRENDS CONTINUE TO HOLD. A SMALL CRAFT ADVISORY WILL EVENTUALLY  
BE NEEDED FOR THE NEARSHORE WATERS AS WELL MONDAY INTO TUESDAY,  
FOR INCREASING WINDS AND BUILDING WAVES. SOME GALES MAY OCCUR  
HERE AS WELL DURING THIS PERIOD.  
 
PERIODS OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE  
DEVELOPING LOW FROM AS EARLY AS MONDAY EVENING INTO TUESDAY.  
WINDS WILL TREND NORTHERLY AND WEAKEN BEHIND A COLD FRONT  
TUESDAY NIGHT INTO WEDNESDAY.  
 
WOOD  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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