537  
FXUS63 KIWX 272240  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
540 PM EST THU NOV 27 2014  
   
SYNOPSIS
 
 
ISSUED AT 530 PM EST THU NOV 27 2014  
 
LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO IMPACT SOUTHWESTERN  
LOWER MICHIGAN AND NORTHWESTERN INDIANA TONIGHT. EXPECT SLICK  
ROADS AND REDUCED VISIBILITIES ASSOCIATED WITH THE HEAVIEST SNOW  
BANDS...ESPECIALLY ALONG I-94 BETWEEN BENTON HARBOR AND NEW  
BUFFALO AND ALONG I 80-90 WEST OF I-69. OTHERWISE...EXPECT CLOUDY  
SKIES AND LOWS IN THE TEENS.  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH FRIDAY)  
ISSUED AT 346 PM EST THU NOV 27 2014  
 
A SINGLE BAND OF HEAVY SNOW THAT HAD BEEN WORKING ITS WAY SOUTH  
ALONG THE EAST SHORE OF LAKE MICHIGAN WAS MOVING INLAND OVER  
SOUTHERN LOWER MICHIGAN...AND HAD GENERALLY WEAKENED WHERE THE BAND  
HAD MOVED OVER LAND. THIS BAND HAD PRODUCED UP TO 8 INCHES OF SNOW  
BETWEEN LUDINGTON AND MUSKEGON. OTHER SNOW BANDS WERE DEVELOPING  
OVER THE LAKE NORTHWEST OF BERRIEN COUNTY WERE DELTA T VALUES HAD  
RISEN TO AROUND 20C. THERE WAS GOOD DENDRITIC GROWTH IN THE THE  
CLOUD LAYER PRODUCING LARGE FLAKES THAT HAD FALLEN EARLIER TODAY. AM  
PLANNING TO KEEP THE LAKE EFFECT SNOW ADVISORY IN EFFECT THROUGH  
EARLY THIS EVENING FOR BERRIEN...CASS AND ST JOSEPH COUNTIES IN  
LOWER MICHIGAN. INVERSION HEIGHTS WILL FALL RAPIDLY THIS EVENING AS  
WINDS BACK TO THE WEST CAUSING LAKE EFFECT SNOW SHOWERS TO DIMINISH.  
 
ALTHOUGH LAKE EFFECT SNOW WILL BE DIMINISHING...12KM NAM SUPPORTS A  
CHANCE FOR SNOW OVER NORTHERN AREAS FRIDAY DURING THE DAY AS  
ISENTROPIC LIFT INCREASES PER 290K SURFACE AND MIXING RATIOS RISE TO  
NEAR 3 G/KG. THEREFORE...KEPT A CHANCE FOR SNOW OVER NORTH AND  
NORTHEAST AREAS FRIDAY.  
 

 
   
LONG TERM
 
(FRIDAY NIGHT THROUGH THURSDAY)  
ISSUED AT 346 PM EST THU NOV 27 2014  
 
RELATIVELY BENIGN SYNOPTIC WEATHER PATTERN STILL EXPECTED THROUGH  
THE LONG TERM. WARM AIR ADVECTION UNDERWAY FRI NIGHT. BEST FORCING  
FOR ANY PCPN LOOKS TO MOVE NORTH OF THE AREA BUT DID MAINTAIN A VERY  
LOW CHANCE POP FAR NORTHEAST. IMPRESSIVE WARM AIR ADVECTION ON TAP  
FOR SATURDAY WITH 850MB TEMPS RISING INTO THE TEENS.  
HOWEVER...SURFACE WARMING WILL STILL BE TEMPERED AS MODEL SOUNDINGS  
SHOW A VERY STRONG INVERSION AND INDICATIONS OF LOW CLOUD DECK  
REMAINING ACROSS THE AREA. STILL SHOULD FEEL MUCH WARMER WITH  
READINGS WELL INTO THE 40S AND RUN AT LOWER 50S MOST PLAUSIBLE IN  
THE SOUTHWEST WHERE WARMER THERMAL RIDGE AND POTENTIAL FOR MIXING  
AND CLEARING ARE BEST. A WARM SATURDAY NIGHT EXPECTED WITH LOWS  
STAYING IN THE 40S. 850MB TEMPS COOL ON SUNDAY AHEAD OF MAIN SURFACE  
COLD FRONT BUT VERY WARM START TO THE DAY SHOULD HELP MAX TEMPS  
REACH THE 50S BEFORE FALLING LATE SUNDAY INTO SUNDAY NIGHT. PCPN  
CHANCES REMAIN LOW BUT LIGHT SHOWERS OR QPF STILL INDICATED BY  
MODELS SO AGAIN ALLOWED LOW CHANCE POPS TO RIDE.  
 
UNCERTAINTY CONTINUES FOR NEXT WEEK...ESPECIALLY MID TO LATE WEEK  
WITH SIGNIFICANT MODEL DIFFERENCES. COLD FRONT SHOULD SAG SOUTH OF  
AREA ON MONDAY WITH COOLER TEMPS...A CHANCE FOR LIGHT PCPN NEAR  
FRONT...AND A VERY LOW CHANCE FOR LIGHT LAKE EFFECT SHOWERS BEHIND  
FRONT MONDAY. GEM AND ECMWF SHOW A REINFORCED SHOT OF COLD AIR  
COMING IN MID WEEK WHILE GFS DEVELOPS A STRONG LOW IN THE PLAINS AND  
SURGES A WARM FRONT NORTH. PREFERENCE AT THIS TIME LIES CLOSER TO  
ECMWF AND GEM SO TRENDED FORECAST VARIABLES IN THIS DIRECTION.  
GFS SOLUTION WOULD INDICATE A CHANCE FOR MODERATE RAINFALL WHILE  
ECMWF/GEM WOULD BE COLD WITH SNOW SHOWERS.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)  
ISSUED AT 1256 PM EST THU NOV 27 2014  
 
A SINGLE BAND HAD FORMED NEAR THE EAST SHORE OF LAKE MICHIGAN.  
GIVEN EXTRAPOLATION AND MODEL DATA...EXPECT THIS BAND WILL  
EVENTUALLY TRANSITION TO MULTIPLE BANDS AND MOVE INLAND OVER FAR  
SW LOWER MICH. HAVE ADJUSTED THE TIMING OF SNOW SHOWERS...ESPECIALLY  
AT SBN. CONDITIONS SHOULD IMPROVE AS WINDS BACK.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
MI...LAKE EFFECT SNOW ADVISORY UNTIL 9 PM EST THIS EVENING FOR  
MIZ077>079.  
 
OH...NONE.  
LM...SMALL CRAFT ADVISORY UNTIL 4 AM EST FRIDAY FOR LMZ043-046.  
 

 
 

 
 
SYNOPSIS...MCD  
SHORT TERM...SKIPPER  
LONG TERM...LASHLEY  
AVIATION...SKIPPER  
 
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