165  
FXUS63 KMKX 192344  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
644 PM CDT FRI OCT 19 2018  
   
UPDATE
 
 
NO MAJOR CHANGES TO FORECAST FOR THE REST OF THIS EVENING. CLOUDS  
WILL CONTINUE TO CLEAR FROM THE NORTHWEST OVER THE NEXT FEW HOURS,  
WITH TEMPERATURES FALLING INTO THE UPPER 30S TO AROUND 40 BY  
DAYBREAK SATURDAY. EXPECT WINDS TO REMAIN BREEZY FROM THE WEST AND  
NORTHWEST OVERNIGHT, WITH VERY WINDY CONDITIONS EXPECTED ON  
SATURDAY, WITH FREQUENT NORTHWEST GUSTS TO AROUND 40 MPH.  
 

 
   
AVIATION(00Z TAFS)
 
 
MVFR CLOUDS WILL CLEAR OVER THE NEXT FEW HOURS. NORTHWEST WINDS  
WILL REMAIN BREEZY OVERNIGHT, WITH LLWS DEVELOPING AS WINDS REMAIN  
STRONG JUST OFF THE SURFACE. VERY WINDY CONDITIONS ARE EXPECTED ON  
SATURDAY, WITH FREQUENT NORTHWEST GUSTS TO AROUND 30 KNOTS. SOME  
SHOWERS WILL BE POSSIBLE ON SATURDAY AS WELL, BUT CONDITIONS ARE  
EXPECTED TO REMAIN VFR.  
 

 
   
MARINE
 
 
OPEN WATERS... HAVE UPGRADED THE GALE WATCH FOR SATURDAY TO A  
GALE WARNING, MERGING IT WITH THE EXISTING GALE WARNING. AS A  
RESULT, A GALE WARNING IS IN EFFECT FROM NOW THROUGH LATE SATURDAY  
EVENING. THERE WILL LIKELY BE A SHORT LULL AFTER MIDNIGHT WHERE  
WINDS MAY NOT QUITE REACH GALE FORCE, BUT THIS WILL BE SHORT LIVED  
BEFORE WINDS PICK UP AGAIN SATURDAY MORNING. A FEW GUSTS TO 40  
KNOTS WILL BE POSSIBLE AT TIMES ON SATURDAY, ESPECIALLY ACROSS THE  
EASTERN PORTIONS OF THE LAKE.  
 
WATERSPOUTS ARE ALSO POSSIBLE ON SATURDAY, ESPECIALLY OVER THE  
SOUTHERN HALF TO 2/3 OF LAKE MICHIGAN.  
 
NEARSHORE...GUSTY WINDS WILL CONTINUE TONIGHT, WITH A SMALL CRAFT  
ADVISORY IN EFFECT THROUGH 10 AM ON SATURDAY. WINDS WILL THEN  
INCREASE FROM THE NORTHWEST, WITH GALES EXPECTED THROUGH SATURDAY  
EVENING.  
 

 
   
PREV DISCUSSION
 
(ISSUED 237 PM CDT FRI OCT 19 2018)  
 
DISCUSSION...  
 
TONIGHT AND SATURDAY...FORECAST CONFIDENCE IS HIGH.  
 
A COLD FRONT WILL SWEEP ACROSS THE AREA THIS EVENING WITH CLEARING  
SKIES IN ITS WAKE. A REINFORCING SHOT OF COLDER AIR ARRIVES ON  
SATURDAY AS A VERY STRONG MID LEVEL SHORT WAVE PLOWS SOUTHEAST  
ACROSS THE AREA SATURDAY MORNING. IT WILL EXIT SOUTH OF WISCONSIN  
BY 18Z SATURDAY, TAKING ANOTHER SURFACE COLD FRONT ALONG WITH IT.  
 
WE SHOULD SEE SOME SHOWERS PUSH THROUGH THE AREA SATURDAY MORNING.  
THE SOUNDINGS LOOK JUST WARM ENOUGH IN THE LOW LEVELS TO KEEP IT  
ALL RAIN BEFORE THE PRECIP EXITS LATER IN THE MORNING. THERE  
COULD BE A BRIEF MIX WITH SNOW NORTHWEST OF MADISON, BUT NOT  
ENOUGH TO HIGHLIGHT. STEEP LOW LEVEL LAPSE RATES WILL HELP BRING  
STRONG/GUSTY NORTHWEST WINDS TO THE AREA IN THE AFTERNOON. HIGH  
TEMPS WOULD LIKELY OCCUR IN THE MORNING, THEN FALL DURING THE  
AFTERNOON.  
 
EXPECT THE WINDS TO DIMINISH QUICKLY SATURDAY EVENING.  
 
SATURDAY NIGHT THROUGH MONDAY - CONFIDENCE...MEDIUM  
A COLDER AIRMASS WILL CONTINUE TO SETTLE IN SATURDAY NIGHT.  
ON SUNDAY A RETURN SOUTHWEST WIND SETS UP THAT WILL RESULT IN A  
WAA REGIME SHUNTING TO THE EAST THE LOW LEVEL THERMAL TROUGH. THE  
WAA CONTINUES INTO MONDAY AHEAD OF THE NEXT DRY COLD FRONT.  
 
MONDAY NIGHT THROUGH WEDNESDAY NIGHT - CONFIDENCE...MEDIUM  
NEXT COLD FRONT ARRIVES MONDAY NIGHT WITH A THERMAL RIDGING BEING  
REPLACED BY A COLD AIR ADVECTION ON NORTH WINDS. HIGH PRESSURE  
WILL BUILD IN ON TUESDAY AND DOMINATE FOR THIS PERIOD.  
 
THURSDAY AND FRIDAY - CONFIDENCE...MEDIUM  
THE HIGH WILL SHIFT THROUGH THE EASTERN LAKES/OHIO VALLEY TO THE  
EASTERN SEABOARD THIS PERIOD AND THIS WILL SET UP A MILDER RETURN  
FLOW. THE 00Z ECMWF WAS QUICKER ON BRINGING RAIN INTO THE AREA  
WHILE THE CORRESPONDING RUINS OF THE GFS AND GEM WERE SHOWING A  
LONGER INFLUENCE OF THE RETREATING HIGH. THE 12Z GFS HAS SPED UP A  
BIT SHOWING SOME RAIN MOVING INTO PARTS OF THE AREA LATER  
THURSDAY NIGHT INTO FRIDAY HOWEVER THE 12Z HAS NOW BACKED OFF  
BEING MORE IN LINE WITH THE OVERALL TRENDS OF THE GFS.  
 

 
   
MKX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
LM...GALE WARNING UNTIL 10 PM CDT SATURDAY FOR LMZ080-669-671-673-675-  
777-779-870-872-874-876-878-261-362-364-366-563-565-567-868.  
 
SMALL CRAFT ADVISORY UNTIL 10 AM CDT SATURDAY FOR LMZ643>646.  
 
GALE WARNING FROM 10 AM TO 10 PM CDT SATURDAY FOR LMZ643>646.  
 

 
 

 
 
UPDATE...BOXELL  
TONIGHT/SATURDAY AND AVIATION/MARINE...BOXELL  
SATURDAY NIGHT THROUGH FRIDAY...99  
 
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