237  
FXUS63 KMKX 190231  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
931 PM CDT MON MAR 18 2024  
   
KEY MESSAGES
 
 
- POLAR AIRMASS OVER THE REGION FOR MUCH OF THE WEEK WITH THE  
EXCEPTION OF A BRIEF MILD PERIOD ON TUESDAY.  
 
- SNOW ACCUMULATIONS ARE POSSIBLE LATE THURSDAY THROUGH THURSDAY  
NIGHT. THE NEXT SYSTEM DEVELOPS SATURDAY NIGHT AND CONTINUES  
THROUGH SUNDAY NIGHT.  
 

 
   
UPDATE
 
 
ISSUED 930 PM CDT MON MAR 18 2024  
 
NO MAJOR CHANGES TO THE FORECAST THIS EVENING. MID-LEVEL CLOUDS  
ASSOCIATED WITH 850HPA WAA HAVE BEGUN TO MAKE THEIR WAY INTO  
SOUTHERN WISCONSIN WHICH MAY KEEP LOW TEMPERATURES A FEW DEGREES WARMER  
OVERNIGHT, ESPECIALLY IN AREAS CLOSER TO CENTRAL WISCONSIN.  
OTHERWISE, DRY AND WINDY CONDITIONS ARE STILL EXPECTED ON  
TUESDAY.  
 
FALKINHAM  
 

 
   
SHORT TERM
 
 
ISSUED 421 PM CDT MON MAR 18 2024  
 
TONIGHT THROUGH WEDNESDAY:  
 
WESTERLY WINDS WILL DIMINISH INTO THIS EVENING BEFORE SHIFTING  
TO SOUTHWESTERLY AND INCREASING LATE TONIGHT AHEAD OF A LOW  
PRESSURE SYSTEM PROGRESSING ACROSS SOUTHERN ONTARIO LATE TONIGHT  
INTO THURSDAY MORNING. EXPECT LOWS IN THE UPPER 20S TO NEAR 30  
DEGREES TONIGHT. A BRIEF PERIOD OF CLOUD COVER ASSOCIATED WITH  
THE INITIATION OF WAA LATE TONIGHT MAY KEEP TEMPERATURES  
FROM FALLING INTO THE 20S IN CENTRAL WISCONSIN.  
 
TUESDAY MORNING, DRY AND GUSTY CONDITIONS ARE EXPECTED, WITH A  
COLD FRONT DRAPED SOUTH OF THE LOW PRESSURE SYSTEM PROGRESSING  
THROUGH SOUTHERN WISCONSIN TUESDAY AFTERNOON AND SHIFTING WINDS  
NORTHWESTERLY. GENERALLY EXPECTING DRY AND WINDY CONDITIONS,  
WITH DEWPOINT DEPRESSIONS AS THE MAIN FORECAST CHALLENGE. A  
POCKET OF SUBSIDING MOIST AIR RIDING ALONG THE BACK SIDE OF THE  
EXITING SHORTWAVE AND MIXING HEIGHTS RISING TO NEAR 5000 FT  
AHEAD OF THE COLD FRONT MAY RESULT IN DEWPOINT TEMPERATURES  
RISING TO THE UPPER 20S. ON THE OTHER HAND, DEWPOINT  
TEMPERATURES IN THE LOWER TEENS ARE EXPECTED TO ADVECT INTO THE  
AREA AND MAY KEEP MOISTURE LEVELS LOWER THAN MODELING INDICATES  
DURING PEAK MIXING HOURS. THE MAIN IMPACT OF THIS CONCERN IS THE  
RELATIVE HUMIDITY VALUES FALLING INTO THE 20 PERCENT RANGE IF  
DRY CONDITIONS PREVAIL, WHICH COULD LEAD TO FIRE WEATHER  
CONCERNS. EXPECT HIGH TEMPERATURES IN THE UPPER 40S TO NEAR 50  
DEGREES.  
 
TUESDAY NIGHT, CLEAR SKIES AND NORTHWESTERLY WINDS WILL LEAD TO  
LOWS IN THE LOWER 20S.  
 
WEDNESDAY, NORTHWESTERLY WINDS AND MIXING HEIGHTS UP TO 5000 FT  
WILL BRING IN DRIER AND COOLER AIR, WITH HIGHS IN THE MID-30S.  
RELATIVE HUMIDITY VALUES MAY FALL TO NEAR 20 PERCENT IN  
SOUTHWESTERN WISCONSIN.  
 
MH  
 

 
   
LONG TERM
 
 
ISSUED 421 PM CDT MON MAR 18 2024  
 
WEDNESDAY NIGHT THROUGH MONDAY:  
 
AFTER A QUIET AND COOL WEDNESDAY NIGHT AND THURSDAY, THE PATTERN  
SHIFTS TO BECOME MORE ACTIVE THURSDAY NIGHT THROUGH THE WEEKEND.  
THE FIRST SYSTEM TO KEEP AN EYE ON IS A CAA DRIVEN TROUGH  
PROPAGATING SOUTHWARD THROUGH SOUTHERN WISCONSIN THURSDAY NIGHT  
INTO FRIDAY. THE GFS APPEARS TO BE THE OUTLIER AND PRODUCES A  
CLOSED LOW, LEADING TO A DEFORMATION BAND AND POTENTIALLY HIGHER  
PRECIPITATION AMOUNTS. MEANWHILE, THE ECMWF AND CANADIAN KEEP  
THE TROUGH OPEN WITH MUCH LESS PRECIPITATION. FOR THE TIME  
BEING, CONFIDENCE REMAINS IN ACCUMULATING SNOWFALL DURING THE  
MORNING COMMUTE ON FRIDAY, WITH SNOW LIKELY (70 TO 90 PERCENT  
CHANCE) THROUGHOUT THE OVERNIGHT HOURS THURSDAY INTO EARLY  
FRIDAY MORNING. SNOW TAPERS OFF THROUGH FRIDAY.  
 
THE NEXT SYSTEM IN THE LONG RANGE DEVELOPS SATURDAY, WITH MODEL  
DISCREPANCY REMAINING QUITE HIGH. GFS DEEPENS THE PREVIOUS  
SYSTEM OFF THE GULF STREAM AND DRAGS AN ARCTIC AIRMASS INTO  
WISCONSIN AHEAD OF THE NEXT SYSTEM, LEADING TO DEEP, COLD AIR  
AND SNOW POTENTIAL ALONG THE WARM FRONT. HOWEVER, ECMWF AND  
CANADIAN FAVOR A LESS INTENSE ATLANTIC SYSTEM AND THEREFORE LESS  
COLD AIR IN PLACE AHEAD OF THE WARM FRONTAL FEATURE. THIS WOULD  
LEAD TO MORE OF A RAINFALL CONCERN. ALL SOLUTIONS REMAIN  
CONSISTENT WITH A BLOCKING GREENLAND HIGH, LEADING TO A  
PERSISTENT PRECIPITATION PATTERN THROUGH EARLY NEXT WEEK.  
 
MH  
 

 
   
AVIATION
 
 
ISSUED 930 PM CDT MON MAR 18 2024  
 
MID-LEVEL CEILINGS AROUND 10KFT ASSOCIATED WITH WAA HAVE BEGUN  
TO MAKE THEIR WAY INTO SOUTHERN WISCONSIN THIS EVENING. THESE  
CLOUDS ARE EXPECTED TO MOSTLY DISSIPATE BY TUESDAY MORNING, WITH DIURNAL  
CUMULUS AROUND 5KFT THEN EXPECTED TO DEVELOP TUESDAY AFTERNOON.  
HOWEVER, VFR CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD.  
 
LOW LEVEL WIND SHEAR IS EXPECTED AT MSN AND JVL LATE TONIGHT  
INTO TUESDAY MORNING AS 850HPA WINDS OF 40-45KT MOVE THROUGH  
SOUTHWESTERN WISCONSIN. GUSTY NORTHWESTERLY WINDS OF AROUND 25KT  
ASSOCIATED WITH BOUNDARY LAYER MIXING OF THESE HIGHER WIND  
SPEEDS AND A COLD FRONT PROGRESSING THROUGH WISCONSIN WILL  
IMPACT ALL SITES ON TUESDAY. WINDS WILL THEN DECELERATE TUESDAY  
NIGHT.  
 
FALKINHAM  
 

 
   
MARINE
 
 
ISSUED 421 PM CDT MON MAR 18 2024  
 
NORTHWESTERLY WINDS WILL CONTINUE TO SLOWLY DIMINISH THROUGH THIS  
AFTERNOON, SHIFTING TO BECOME WESTERLY THIS EVENING AND INCREASING  
OVERNIGHT AS HIGH PRESSURE BUILDS SOUTHWARD INTO THE LOWER  
MISSISSIPPI VALLEY AND LOW PRESSURE MOVES SOUTHEASTWARD ACROSS  
SOUTHERN ONTARIO. A FEW GUSTS MAY APPROACH GALE FORCE ACROSS THE  
SOUTHERN HALF OF THE LAKE TUESDAY MORNING. WINDS WILL SHIFT TO  
NORTHWESTERLY TUESDAY AFTERNOON AS AN ASSOCIATED COLD FRONT  
SINKS SOUTHEAST ACROSS THE LAKE. A SMALL CRAFT ADVISORY IS IN  
EFFECT EARLY TUESDAY MORNING THROUGH TUESDAY EVENING DUE TO  
ELEVATED WINDS. BUILDING HIGH PRESSURE IN THE NORTHERN GREAT  
PLAINS MAY RESULT IN A FEW GALES IN THE NORTHERN HALF OF THE  
LAKE WEDNESDAY AS THE LOW EXITS.  
 
WINDS WILL REMAIN NORTHWESTERLY THROUGH WEDNESDAY, SLOWLY  
DIMINISHING INTO THURSDAY.  
 
MH  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
LM...GALE WARNING...LMZ080-LMZ673-LMZ675-LMZ777-LMZ779-LMZ874-  
LMZ876-LMZ878...4 AM TUESDAY TO 1 PM TUESDAY.  
 
SMALL CRAFT ADVISORY...LMZ643-LMZ644-LMZ645-LMZ646...4 AM  
TUESDAY TO 7 PM TUESDAY.  
 

 
 

 
 
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