494  
FXUS63 KMKX 211434  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
934 AM CDT FRI AUG 21 2026  
   
KEY MESSAGES  
 
- SHOWERS & STORMS THROUGH NOON. WIDESPREAD SEVERE WEATHER NOT  
EXPECTED IN THIS ACTIVITY.  
 
- SCATTERED SHOWERS AND THUNDERSTORMS (30 TO 50 PERCENT CHANCES)  
WITH PASSING COLD FRONT ARE EXPECTED THIS AFTERNOON AND  
EVENING. DAMAGING WINDS ARE THE MAIN THREAT.  
 
- SMALL CHANCES (20 TO 40 PERCENT) FOR A SHOWER OR STORM  
SATURDAY AFTERNOON FOR PORTIONS OF EAST CENTRAL AND SOUTHEAST  
WISCONSIN.  
 
 
   
MESOSCALE UPDATE  
 
ISSUED 930 AM CDT FRI AUG 21 2026  
 
MAINLY SUB-SEVERE SHOWERS AND STORMS CONTINUE THROUGH NOON.  
MONITORING ATMOSPHERIC RECOVERY INTO THE AFTERNOON FOR  
ADDITIONAL STORM REDEVELOPMENT (SOME POSSIBLY STRONG-SEVERE).  
 
EAST-WEST LINE OF ELEVATED THUNDERSTORMS CONTINUES TO SAG  
SOUTHEAST ACROSS THE REGION THIS MORNING. ACTIVITY IS ONGOING  
NEAR THE NOSE OF A 925-850 MB THETA-E PLUME ORIGINATING FROM THE  
CENTRAL PLAINS, WITH AFFILIATED WARM ADVECTION CONTINUING TO  
SUPPORT THE DEVELOPMENT OF NEW CELLS ALONG THE WESTERN PERIPHERY  
OF THE LINE. GIVEN THE MECHANISMS IN PLAY, ANTICIPATING THIS  
LINE OF STORMS TO MAKE IT ALL THE WAY THROUGH SOUTHERN WISCONSIN  
THROUGH THE REST OF THE MORNING HOURS. HAVE UPPED PRECIP  
PROBABILITIES THROUGH NOON TO ACCOUNT FOR NEAR-TERM  
EXPECTATIONS. GIVEN ELEVATED NATURE TO THE STORMS, IN ADDITION  
TO THEIR SEPARATION FROM A PLUME OF SURFACE-BASED THETA-E &  
INSTABILITY CLOSER TO THE MISSISSIPPI RIVER, NOT ANTICIPATING  
MUCH OF A DAMAGING WIND THREAT IN THESE STORMS. CAN EXPECT A  
BRIEF HIT OF TORRENTIAL RAINFALL AND FREQUENT CLOUD TO GROUND  
LIGHTNING AS ACTIVITY MOVES THROUGH. MOVE INDOORS AS THESE  
STORMS APPROACH.  
 
ONCE THESE INITIAL STORMS DEPART FOLLOWING THE NOON HOUR,  
FORECAST CONCERNS SHIFT TOWARD ATMOSPHERIC RECOVERY THROUGH  
EARLY AFTERNOON. SAID RECOVERY WILL RESIDE IN THE AMOUNT OF  
CLOUD DEBRIS LEFTOVER FROM MORNING STORMS, IN ADDITION TO THE  
EASTWARD PROGRESS OF A SURFACE WARM FRONT CURRENTLY NEAR THE  
MISSISSIPPI RIVER. THE WARM FRONT SERVES AS THE EASTERN BOUND  
OF WHAT WILL BECOME A NARROW BUT UNSTABLE WARM SECTOR AHEAD OF A  
COLD FRONT CURRENTLY NEAR THE TWIN CITIES. THE FURTHER THE WARM  
FRONT MAKES IT INTO SOUTHERN WISCONSIN, THE GREATER THE AREA  
THAT WILL BECOME UNSTABLE & FAVORABLE FOR STORM RE-DEVELOPMENT  
AFTER 3 PM. WILL THUS BE MONITORING THIS PROGRESS CLOSELY OVER  
THE NEXT SEVERAL HOURS, AS IT REMAINS UNCERTAIN HOW FAR EAST THE  
WARM FRONT WILL MAKE IT. ANYWHERE THAT DOES BECOME FAVORED FOR  
STORM RE-DEVELOPMENT WILL NEED TO BE WATCHED FOR SEVERE WEATHER  
IMPACTS, WITH LARGE HAIL, DAMAGING WINDS, AND AN ISOLATED  
TORNADO ALL POSSIBLE. STAY WEATHER AWARE INTO THIS EVENING.  
 
QUIGLEY  
 
 
   
SHORT TERM  
 
ISSUED 1100 PM CDT THU AUG 20 2026  
 
TONIGHT THROUGH SATURDAY NIGHT:  
 
TONIGHT SHOULD REMAIN LARGELY QUIET OUTSIDE OF A FEW LIGHT  
SHOWERS NUDGING INTO THE REGION BUT DESPITE SOME PVA PUSHING  
THROUGH AND LOW LEVEL WAA THE LOW LEVEL MOISTURE MAY BE TOO DRY  
INITIALLY TO BRING SHOWERS TO THE GROUND. AROUND DAYBREAK  
FRIDAY WE EXPECT SOME LOW LEVEL MOISTURE TO ALLOW FOR PRECIP  
CHANCES TO INCREASE FOR A BRIEF PERIOD IN THE MORNING. THE  
FORCING APPEARS TO BE LARGELY FOCUSED ALONG THE SHORTWAVE WITH  
SUPPLEMENTARY WAA AND BETTER MOISTURE BUT CAMS DO NOT SEEM TO  
FAVOR WIDESPREAD SHOWERS IN THE MORNING WITH BETTER CHANCES  
FOCUSED FURTHER WEST CLOSER TO THE SURFACE FRONT. AS THE FRONT  
PUSHES EAST MOISTURE SEEMS TO IMPROVE INTO FRIDAY AFTERNOON AND  
EVENING. CAMS SEEM TO FAVOR SOME DEVELOPMENT OF CONVECTION  
FRIDAY LATE AFTERNOON ON THE WESTERN HALF OF THE CWA WITH A  
SECONDARY DEVELOPMENT POTENTIAL INTO THE EARLY EVENING CLOSER TO  
THE LAKE. GIVEN HIGHER INSTABILITY (>2000 J/KG) AND ENOUGH  
SHEAR (30-35KTS) WE SHOULD SEE A STRONGER STORM OR TWO FOR A  
BRIEF PERIOD BUT THE LACK OF BETTER SHEAR SHOULD LIMIT THE  
POTENTIAL TO JUST A FEW STORMS AT MOST WITH THE PRIMARY CONCERNS  
BEING 1 INCH HAIL AND BRIEF DAMAGING WINDS.  
 
QUIETER CONDITIONS OVERNIGHT FRIDAY INTO SATURDAY MORNING AS THE  
SURFACE LOW PUSHES OUT. HOWEVER, SATURDAY LATE MORNING AND  
AFTERNOON WE WILL LIKELY SEE A BACKDOOR COLD FRONT COMBINED WITH  
LAKE BREEZE CONVERGENCE ZONE IN THE NEARSHORE REGION BRING  
ADDITIONAL PRECIP CHANCES FOR EASTERN PORTIONS OF THE CWA. THERE  
IS SOME UNCERTAINTY FOR THIS PRIMARILY WITH RESPECT TO LOW TO  
MID LEVEL MOISTURE AND HOW WIDESPREAD IT WILL BE BUT SOME  
SHOWERS AND PERHAPS A FEW STORMS WILL BE POSSIBLE WITH THIS. IF  
WE CAN MANAGE A FEW STORMS WE COULD SEE SOME BECOME STRONG  
GIVEN A DECENT AMOUNT OF DEEP LAYER SHEAR THOUGH THIS DIFFERS  
SIGNIFICANTLY BETWEEN THE CAMS AND SYNOPTIC SCALE MODELS SO WE  
WILL HAVE TO MONITOR THOSE CONDITIONS THROUGH FRIDAY. THIS WILL  
BE WORTH MONITORING SATURDAY AFTERNOON GIVEN SOME POTENTIALLY SNEAKY  
CONDITIONS. CHANCES WILL RAPIDLY DECREASE SATURDAY EVENING AS  
WE LOSE INSTABILITY AND FORCING PUSHES OUT.  
 
KUROSKI  
 
 
   
LONG TERM  
 
ISSUED 1100 PM CDT THU AUG 20 2026  
 
SUNDAY THROUGH FRIDAY:  
 
SUNDAY AND MONDAY WILL FEATURE HIGH PRESSURE BUILDING INTO THE  
REGION KEEPING THINGS DRY THROUGH MONDAY. THINGS HAVE TRENDED  
OVERALL DRIER INTO TUESDAY WITH THE HIGH PRESSURE LINGERING A  
BIT LONGER WITH TUESDAY NIGHT WEDNESDAY BECOMING OUR NEXT BEST  
CHANCE FOR SHOWERS AND STORMS AS AND 850MB FRONT AND UPPER LEVEL  
SHORTWAVE SWING THROUGH WITH SOME WAA. STILL SOME UNCERTAINTY  
IN TRACK AND TIMING BUT MODELS GENERALLY AGREE ON THIS PUSHING  
THROUGH BRINGING PRECIP WITH LIKELY SOME STORMS AS WELL. IN  
ADDITION, DEEP LAYER SHEAR APPEARS TO BE STRONG IN THE 40-50KT  
RANGE WHICH WOULD BRING SOME SEVERE RISK IF THE TIMING OF STORMS  
IS INTO THE EVENING.  
 
AFTER WEDNESDAY, UNCERTAINTY INCREASES QUITE A BIT THOUGH IN  
GENERAL HIGHER PRESSURE SEEMS TO BE PUSHING IN WITH DRIER  
CONDITIONS OVERALL MORE LIKELY.  
 
KUROSKI  
 
 
   
AVIATION  
 
ISSUED 600 AM CDT FRI AUG 21 2026  
 
STORMS (NON-SEVERE) ARE LIKELY FOR EAST CENTRAL WI, BUT ARE  
LOOKING LESS LIKELY FOR SOUTH CENTRAL AND SOUTHEAST WI THIS  
MORNING. CLOUD BASES IN ANY STORMS TOWARD CENTRAL WI COULD DROP  
TO 2500FT, BUT WOULD BE AROUND 5000FT ELSEWHERE. LOOK FOR  
STEADY SOUTHWEST WINDS ACROSS SOUTHERN WI TODAY WITH A GENERAL  
LULL IN STORM ACTIVITY. THEN ISOLATED TO SCATTERED STORMS ARE  
EXPECTED TO DEVELOP IN SOUTH CENTRAL WI MID AFTERNOON AND TREK  
EASTWARD THROUGH EARLY EVENING. A FEW STRONG TO SEVERE STORMS  
ARE POSSIBLE WITH DAMAGING WINDS THE MAIN THREAT. WINDS WILL  
BECOME NORTHWEST THIS EVENING AFTER THE PASSAGE OF A COLD FRONT.  
 
CRONCE  
 
 
   
MARINE  
 
ISSUED 600 AM CDT THU AUG 20 2026  
 
SOUTH TO SOUTHWEST WINDS WILL INCREASE TODAY AS A LOW PRESSURE  
TROUGH OF 29.8 INCHES APPROACHES SOUTHERN WISCONSIN FROM THE  
MINNESOTA ARROWHEAD. THUNDERSTORMS ARE EXPECTED AT TIMES TODAY  
THROUGH TONIGHT. THE TROUGH WILL CROSS LAKE MICHIGAN FROM NORTH  
TO SOUTH TONIGHT AND BRING A WIND SHIFT TO THE NORTHWEST. THEN LOOK  
FOR GUSTY NORTHERLY WINDS TO DEVELOP ALONG A COLD FRONT THAT WILL  
TRACK FROM NORTH TO SOUTH DOWN LAKE MICHIGAN SATURDAY EVENING. A  
FEW THUNDERSTORMS ARE POSSIBLE ALONG THIS FRONT. NORTHERLY WINDS  
WILL PERSIST THROUGH SUNDAY AS LOW PRESSURE AROUND 29.6 INCHES  
TRACKS FROM LOWER MICHIGAN TO ONTARIO. VARIABLE WINDS ARE  
EXPECTED FOR MONDAY AND TUESDAY AS HIGH PRESSURE OF 30.1 INCHES  
CROSSES THE UPPER GREAT LAKES.  
 
CRONCE  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
LM...NONE.  
 
 
 
 
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