459  
FXUS63 KMKX 202133  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
333 PM CST MON JAN 20 2020  
   
SHORT TERM
 
 
TONIGHT THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE IS HIGH.  
 
THE LAST OF THE LOW CLOUDS ARE FINALLY SCATTERING OUT THIS  
AFTERNOON AND SKIES SHOULD BE CLEAR TONIGHT WITH HIGH PRESSURE  
NOSING IN FROM THE NORTHERN PLAINS. THE ONLY UNCERTAINTY IS THE  
POTENTIAL FOR SOME LIGHT FOG TO DEVELOP. GIVEN LOW DEWPOINTS AND  
DRY AIR IN PLACE, OPTED TO LEAVE THIS OUT OF THE FORECAST. TEMPERATURES  
SHOULD FALL INTO THE SINGLE DIGITS ACROSS SOUTHERN WI TONIGHT  
WITH AN EXPECTED INVERSION. MANY MODELS ARE LEANING TOWARD A  
SLIGHTLY WARMER FORECAST, PROBABLY DUE TO BIAS CORRECTION, SO I  
UNDERCUT THE GUIDANCE.  
 
SUNNY SKIES WILL GIVE WAY TO MID LEVEL CLOUDS MOVING IN BY TUESDAY  
EVENING. HIGHS TOMORROW WILL BE IN THE LOWER 20S, SIMILAR TO  
TODAY. LOWS TUESDAY NIGHT WILL BE MORE MILD THAN TONIGHT, WITH A  
QUICK DROP-OFF IN THE EVENING AND THEN GRADUAL WARMING OVERNIGHT.  
   
LONG TERM
 
 
WEDNESDAY AND WEDNESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM/HIGH...  
 
THE NEXT SYSTEM IS EXPECTED TO START PUSHING IN FROM THE WEST  
WEDNESDAY ALONG A FRONTAL BOUNDARY WITH SOME INFLUENCE FROM AN UPPER  
LEVEL SHORTWAVE. THERE REMAINS SOME UNCERTAINTY WITH THE TIMING AS  
THE LOW PRESSURE SYSTEM PULLS NORTHEAST BUT GENERALLY THE WESTERN  
HALF OF THE CWA SHOULD SEE SOME PRECIPITATION, LIKELY SNOW. HOWEVER,  
ACCUMULATIONS ARE EXPECTED TO REMAIN LIGHT AT THIS POINT.  
 
THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS MEDIUM...  
 
AS THE WEDNESDAY SYSTEM PULLS OUT THERE MAY BE A LULL IN THE  
PRECIPITATION AS THE NEXT SYSTEM PUSHES NORTHEAST THURSDAY INTO  
FRIDAY. THERE STILL REMAINS PLENTY OF UNCERTAINTY IN THIS PERIOD  
GENERALLY WITH THE MOST OF THE UNCERTAINTY COMING FROM INCONSISTENCY  
ACROSS MODELS IN THE FORCING ALOFT. MOSTLY SNOW IS EXPECTED FOR THIS  
PERIOD BUT WARMER TEMPERATURES MAY CAUSE SOME MIXED PRECIP. THE  
SYSTEM INITIALLY EXPECTED FRIDAY NIGHT LOOKS TO HAVE DRIFTED  
SOUTHEAST IN ITS TRACK THUS LIKELY NOT IMPACTING THE CWA AS MUCH AS  
INITIALLY EXPECTED. HOWEVER, THERE IS STILL UNCERTAINTY IN THE TRACK  
OF THIS SYSTEM AND WE EXPECTED THE TRACK TO CONTINUE TO CHANGE SO WE  
WILL CONTINUE TO MONITOR HOW THIS SYSTEM CHANGES.  
 
SUNDAY THROUGH MONDAY...FORECAST CONFIDENCE IS LOW...  
 
GIVEN THE UNCERTAINTIES IN THE SYSTEM TRACK FRIDAY NIGHT INTO  
SATURDAY, SUNDAY AND MONDAY BECOME VERY UNCERTAIN. MODELS SHOW VERY  
DIFFERENT SOLUTIONS IN THE UPPER LEVELS WITH VAST DIFFERENCES IN  
FORCING. THUS THIS PERIOD SHOULD BECOME MORE CLEAR AS MODELS BEGIN  
TO MORE CLOSELY ALIGN AS WE GET A BETTER IDEA OF WHAT WILL HAPPEN  
WITH THE SYSTEM FRIDAY NIGHT INTO SATURDAY. HOWEVER THE PERIOD LOOK  
LIKELY TO REMAIN DRY AT THIS POINT.  
 

 
   
AVIATION(21Z TAF UPDATE)
 
 
THE MVFR CLOUDS ARE DIMINISHING THIS AFTERNOON AS DRIER AIR AND  
HIGH PRESSURE WORK THEIR WAY INTO SOUTHERN WI. EXPECT CLEAR SKIES  
TONIGHT. THERE IS A CHANCE FOR PATCHY FOG, BUT WILL KEEP IT OUT OF  
THE FORECAST FOR NOW DUE TO LOW CONFIDENCE. VFR CONDITIONS  
THROUGH TUESDAY EVENING.  
 

 
   
MARINE
 
 
HIGH PRESSURE SPREADING INTO THE GREAT LAKES FROM THE  
NORTHERN PLAINS WILL BRING LIGHT WINDS TO THE REGION THROUGH  
TUESDAY MORNING. EXPECT INCREASING SOUTHWEST WINDS TUESDAY  
AFTERNOON INTO TUESDAY NIGHT WITH THE DEPARTING HIGH. GALE FORCE  
GUSTS ARE POSSIBLE OVER THE NORTH THIRD OF LAKE MICHIGAN TUESDAY  
NIGHT THROUGH WEDNESDAY.  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
LM...NONE.  

 
 

 
 
TONIGHT/TUESDAY AND AVIATION/MARINE...CRONCE  
TUESDAY NIGHT THROUGH MONDAY...ARK  
 
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