077  
FXUS63 KMKX 242044  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
344 PM CDT WED APR 24 2024  
   
KEY MESSAGES
 
 
- FREEZE WARNING MIDNIGHT UNTIL 8 AM FOR BELOW-FREEZING  
TEMPERATURES.  
 
- ACTIVE PATTERN FRIDAY THROUGH THIS WEEKEND. MULTIPLE ROUNDS OF  
SHOWERS/STORMS WILL RESULT IN LOCALLY HEAVY RAINFALL. THE  
SEVERE STORM RISK IS MORE UNCERTAIN, BUT BEARS MONITORING.  
 

 
   
SHORT TERM
 
 
ISSUED 344 PM CDT WED APR 24 2024  
 
TONIGHT AND THURSDAY:  
 
WITH DEWPOINTS IN THE UPPER 20S THIS AFTERNOON, AND UPPER TEENS  
TOWARD CENTRAL WI, CONFIDENCE IN STRONG RADIATIONAL COOLING WITH  
LIGHT WINDS OVERNIGHT IS INCREASING. LOW TEMPERATURES SHOULD  
DROP TO AROUND 29 OR 30, WITH 28 A VALID CONCERN. THE FORECAST  
TEMPERATURES ARE AROUND THE 50TH PERCENTILE OF THE NBM AND THE  
MEDIAN OF MANY MODELS. A FREEZE WARNING IS IN EFFECT. TEMPERATURES  
IN THE UPPER 20S FOR A FEW HOURS CAN CAUSE DAMAGE TO BLOSSOMING  
FRUIT TREES.  
 
CLEAR SKIES ARE EXPECTED TONIGHT THROUGH THURSDAY, THANKS TO  
HIGH PRESSURE AND DRY AIR OVER THE GREAT LAKES. WITH ONSHORE  
WINDS, LAKESHORE AREAS WILL REMAIN COOL THURSDAY WHILE INLAND  
TEMPS SHOULD BE A LITTLE WARMER THAN TODAY, AROUND 60. LOOK FOR  
AFTERNOON WINDS TO BECOME SOUTHEAST 10 TO 15 MPH AND REMAIN  
FAIRLY STEADY OVERNIGHT. LOWS THURSDAY WILL BE MILDER, BETWEEN  
36 AND 42, DUE TO INCREASING CLOUDS AND BREEZIER CONDITIONS.  
 
MODELS CONTINUE TO TREND SLOWER FOR THE PRECIP ARRIVAL IN  
SOUTHERN WI FROM WEST TO EAST ON FRIDAY. IT IS LOOKING LIKE  
PRECIP SHOULD REMAIN WEST OF MADISON UNTIL AT LEAST 3 PM.  
 
CRONCE  
 

 
   
LONG TERM
 
 
ISSUED 344 PM CDT WED APR 24 2024  
 
FRIDAY THROUGH WEDNESDAY:  
 
SYNOPTIC LOOK:  
 
THE START OF A BUSY PATTERN WILL BEGIN ON FRIDAY AND CONTINUE  
INTO THE START OF NEXT WEEK. MODELS ARE IN GOOD AGREEMENT OF A  
MULTI-PART SYSTEM SLOWLY MOVING OUT OF THE DESERT SW AND INTO THE  
PLAINS AND FINALLY ONTO THE GREAT LAKES REGION OVER THE COMING  
DAYS. AT THE SYNOPTIC LEVEL, WE WILL HAVE IN ESSENCE, A DOUBLE  
BARREL TROUGH EJECTION WHICH WILL BE THE FOCUS OF OUR ACTIVE  
WEATHER PATTERN. THE FIRST TROUGH WHICH IS STILL CURRENTLY OFF  
THE COAST OF CALIFORNIA WILL SLOWLY MOVE EASTWARD BEFORE REACHING  
THE PLAINS ON FRIDAY. AROUND THE SAME TIME, A SECONDARY TROUGH  
WILL MOVE INTO THE PACIFIC NORTHWEST AND TREK TOWARDS THE  
SOUTHEAST. ON SATURDAY WE'LL SEE THE THE INITIAL TROUGH WEAKEN AS  
IT MOVES INTO THE GREAT LAKES AREA WITH AN ATTENDANT 50KT+ ZONAL  
JET STREAK SOMEWHERE IN THE VICINITY OF THE WESTERN GREAT LAKES.  
MEANWHILE THE SECONDARY TROUGH AT THIS POINT WILL BE EXITING THE  
ROCKY MOUNTAINS AND MOVING INTO THE CENTRAL PLAINS. OVER THE NEXT  
24 HOURS THIS TROUGH WILL MOVE ON A NE TRACK WHILE SLOWLY FILLING  
IN BEFORE ARRIVING INTO THE MIDWEST LATE ON SUNDAY. THE JET  
STREAK ASSOCIATED WITH THIS TROUGH WILL BE OF SIMILAR MAGNITUDE TO  
THE DAY PRIOR BUT ORIENTATED MUCH MORE MERIDIONAL STRETCHING FROM  
THE DEEP SOUTH AND INTO WESTERN ONTARIO. BY EARLY NEXT WEEK, A  
RIDGE SHOULD BEGIN TO BUILD OVER US PUTTING AN END TO THE ACTIVE  
PATTERN AND INDUCING QUIETER CONDITIONS ACROSS SOUTHERN WISCONSIN.  
 
CONVECTIVE POTENTIAL:  
AS WITH ANY MAJOR TROUGH DURING THE SPRING AND SUMMER SEASON WE  
MUST KEEP AN EYE OUT FOR CONVECTION AND IN SOME CASES EVEN SEVERE  
WEATHER. THIS TIME IS NO DIFFERENT AS WE ARE MONITORING 3 DAYS  
(FRIDAY, SATURDAY, AND SUNDAY) FOR THE POTENTIAL FOR STRONG TO  
SEVERE STORMS. THE LATEST SPC OUTLOOKS HAVE HIGHLIGHTED THE  
SOUTHWESTERN PORTION OF THE CWA IN A MARGINAL RISK ON FRIDAY (DAY  
3). WHILE BOTH SATURDAY AND SUNDAY (DAY 4 AND 5) HAVE THE WESTERN  
PORTIONS OF OUR CWA IN SLIGHT RISKS FOR SEVERE WEATHER. IT SHOULD  
BE NOTED THAT THERE ARE MANY THINGS THAT WILL NEEDED TO BE SORTED  
OUT BEFORE CONFIDENCE IN ANY ONE PARTICULAR SOLUTION GROWS.  
 
FRIDAY INTO SATURDAY AM:  
AT THE ONSET OF THIS PERIOD, THE ENTIRE REGION WILL BE IN A SE  
FLOW REGIME IN ACCORDANCE WITH A INTENSIFYING SUB-1000MB LOW  
ACROSS THE CENTRAL PLAINS. THROUGH MOST OF THE MORNING AND EARLY  
AFTERNOON WE SHOULD SEE PRECIPITATION HOLD OFF DUE TO A DRY LAYER  
NEAR THE SURFACE. HOWEVER, BY LATE AFTERNOON AND EARLY EVENING WE  
SHOULD PRECIPITATION BEGIN TO IMPINGE INTO OUR FAR SW COUNTIES  
TIED TO A LIFTING FRONTAL BOUNDARY. WITH THESE STORMS WE COULD SEE  
SOME SCATTERED SHOWERS AND STORMS MOVE THROUGH THE EVENING AND  
OVERNIGHT HOURS. MODELS ARE SUGGESTING 500-750 J/KG OF MUCAPE  
WHICH COULD ALLOW FOR SOME LIGHTNING, SMALL HAIL AND GUSTY WINDS  
IN SOME OF THE STRONGER CORES THAT REACH OUR CWA. BY SATURDAY  
MORNING, A WIDESPREAD 0.25-0.4" IS LIKELY WITH ISOLATED 0.5-0.75+"  
RAINFALL TOTALS BEING SEEN AS WELL.  
 
SATURDAY INTO SUNDAY AM:  
BY MIDDAY SATURDAY, THE BOUNDARY FROM THE NIGHT PRIOR WILL STALL  
OUT ACROSS NORTHERN WISCONSIN. FOLLOWING IT, AN EML FROM THE SW  
WILL REACH OUR AREA KEEPING US DRY UNTIL THE AFTERNOON WHEN MODELS  
DIVERGE ON THEIR SOLUTIONS. WITH STEEP LAPSE RATES ALOFT FROM THE  
EML WE SHOULD SEE UPWARDS OF 1000J/KG FORM THROUGH THE DAY. TIE IN  
DEWPOINTS REACHING INTO THE MID-60S AND 40+KTS OF BULK SHEAR  
ORGANIZED AND POTENTIALLY SEVERE STORMS ARE POSSIBLE. STORMS COULD  
EITHER FORM ALONG THE SAGGING BOUNDARY OR IN THE OPEN WARM SECTOR  
BUT NEITHER SOLUTION IS FAVORED AT THIS POINT. IT SHOULD BE NOTED  
THAT DUE TO 500MB HEIGHT RISES, CONFIDENCE IN STORM FIRING IN THE  
FIRST PLACE IS LOW WITH NO REAL FORCING MECHANISM IN THE VICINITY.  
TRENDS TOWARDS A DRIER OR TOWARDS A MORE CONVECTIVE SATURDAY  
AFTERNOON/EVENING WILL BE WATCHED FOR IN COMING FORECASTING  
CYCLES.  
 
BY VERY LATE SATURDAY, CONVECTION THAT BEGAN ACROSS THE CENTRAL  
PLAINS WILL EVENTUALLY ARC TO THE NORTHEAST AND REACH OUR AREA.  
ONCE AGAIN THESE STORMS WILL POSE A THREAT FOR RAINFALL -  
POTENTIALLY HEAVY AT TIMES THROUGH THE NIGHT. WIDESPREAD 0.3-0.5"  
IS LIKELY WITH 0.5-1.0" TOTALS POSSIBLE IN STRONGER STORMS OR  
WHERE STORMS TREK OVER MULTIPLE TIMES.  
 
SUNDAY AND ONWARDS:  
 
SUNDAY IS THE DAY WITH THE LEAST AMOUNT OF CONFIDENCE IN WHAT MAY  
TRANSPIRE. BY THIS POINT IN TIME THE EML FROM THE SW WILL HAVE  
BEEN WORKED OUT TO SOME DEGREE BY THE OVERNIGHT. WE ARE LIKELY TO  
SEE CONVECTION THROUGH THE MORNING PERIOD BEFORE SOME TYPE OF  
CLEARING ON SUNDAY APPEARS HEADING INTO THE AFTERNOON. THERE WILL  
ENOUGH SHEAR FOR ORGANIZED STORMS AND ONCE AGAIN SEVERE STORMS IF  
ENOUGH CAPE CAN BUILD IN BEFORE SOME BOUNDARY MOVES THROUGH.  
ANOTHER PERIOD OF HEAVY RAIN IS POSSIBLE SUNDAY AFTERNOON AND INTO  
THE EVENING. THE COLD FRONT WILL FINALLY MOVE THROUGH OUR AREA  
EARLY MONDAY FINALLY PUTTING AN TO OUR ACTIVE WEATHER AS A RIDGE  
BUILDS IN OVER THE AREA.  
 
HYDROLOGICAL CONCERNS:  
ALL IN ALL, TOTAL RAINFALL VALUES WILL LIKELY BE IN THE 1-2.5"  
OVER THE WEEKEND WITH LOCALIZED HIGHER VALUES. WHILE MOST OF OUR  
RIVERS ARE NOT OF CONCERN RIGHT NOW, LOCALIZED PONDING AND  
ISOLATED FLOODING IS POSSIBLE IF WE SEE STORMS FIRE OVER THE  
SAME AREAS ON CONSECUTIVE DAYS. TO THAT DEGREE, THE WPC HAS  
PLACED OUR ENTIRE AREA IN A MARGINAL RISK FOR EXCESSIVE RAINFALL  
ON FRIDAY, SATURDAY, AND SUNDAY.  
 
CRONCE  
 

 
   
AVIATION
 
 
ISSUED 344 PM CDT WED APR 24 2024  
 
VFR CONDITIONS WILL PREVAIL TONIGHT THROUGH THURSDAY WITH HIGH  
PRESSURE OVERHEAD. LOOK FOR SHOWERS AND STORMS TO SPREAD IN FROM  
WEST TO EAST FRIDAY, PROBABLY LATER THAN FORECAST.  
 
CRONCE  
 

 
   
MARINE
 
 
ISSUED 344 PM CDT WED APR 24 2024  
 
WINDS WILL CONTINUE TO DIMINISH OVER LAKE MICHIGAN THIS EVENING  
AND BECOME LIGHT AND VARIABLE THROUGH THURSDAY AFTERNOON AS HIGH  
PRESSURE DRIFTS ACROSS THE GREAT LAKES. LINGERING HIGH WAVES  
WILL CONTINUE TO SUBSIDE SO THE SMALL CRAFT ADVISORY WILL BE  
ALLOWED TO EXPIRE AT 10 PM.  
 
STRONG SOUTHEAST WINDS WILL DEVELOP OVER LAKE MICHIGAN FRIDAY  
AFTERNOON AND BECOME SOUTHERLY SATURDAY MORNING, THEN DIMINISH  
SATURDAY NIGHT. GALES ARE POSSIBLE FRIDAY AFTERNOON THROUGH  
SATURDAY, BUT CONFIDENCE IS LOW DUE TO AN INVERSION AND  
STABILITY FROM WARM AIR FLOWING OVER THE COOL WATER.  
 
CRONCE  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...FREEZE WARNING...WIZ046-WIZ047-WIZ051-WIZ052-WIZ056-WIZ057-  
WIZ058-WIZ059-WIZ060-WIZ062-WIZ063-WIZ064-WIZ065-WIZ066-  
WIZ067-WIZ068-WIZ069-WIZ070-WIZ071-WIZ072...MIDNIGHT  
THURSDAY TO 8 AM THURSDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646 UNTIL 10 PM  
WEDNESDAY.  
 

 
 

 
 
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