801  
FXUS63 KIWX 241958  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
358 PM EDT FRI OCT 24 2014  
   
SYNOPSIS
 
 
ISSUED AT 1106 AM EDT FRI OCT 24 2014  
 
WHILE CONDITIONS ARE EXPECTED TO BE DRY...SKIES TODAY AND TONIGHT  
WILL REMAIN PARTLY TO MOSTLY CLOUDY. AFTERNOON HIGHS WILL REACH  
INTO THE LOW TO MID 60S IN MOST AREAS. LOWS TONIGHT WILL BE IN THE  
UPPER 40S. OTHERWISE...A WARM AND PLEASANT WEEKEND IS IN STORE.  
SKIES WILL BE PARTLY TO MOSTLY CLEAR...WITH HIGHS IN THE 60S AND  
LOW 70S.  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH SATURDAY)  
ISSUED AT 357 PM EDT FRI OCT 24 2014  
 
SIMILAR TO LAST NIGHT...ANOTHER WEAK SHORT WAVE WILL MOVE THROUGH  
THE REGION OVERNIGHT. 12Z MODELS DO SHOW A BIT DEEPER COLUMN OF  
MOISTURE TONIGHT BUT SATELLITE THIS AFTERNOON SHOWING LITTLE IN THE  
WAY OF SYNOPTIC CLOUDS UPSTREAM ASSOCIATED WITH THIS FEATURE.  
HOWEVER...THERE IS STILL QUITE A BIT OF LOW LEVEL STRATUS AND FOG  
ACROSS THE MIDWEST LEFT OVER FROM THIS MORNING. FEELING IS THAT 12Z  
MODELS MAY HAVE PICKED UP ON THIS LOW LEVEL MOISTURE FROM 12Z REGIONAL  
RAOBS...WHICH OTHERWISE ARE QUITE DRY....AND ARE PROJECTING IT  
DOWNSTREAM WITH SYNOPTIC WAVE. SEVERAL MODELS CAME IN WITH A FEW  
HUNDREDTHS QPF WHERE PREVIOUS FORECASTS HAD LITTLE IF ANY. NAM12 AND  
GFS40 DO SHOW A DECENT SHORT WAVE AND VORT MAX BUT MUCH LOWER THAN  
THE TYPICAL 500MB LEVEL. A NICE REFLECTION IS SEEN AROUND 850-700MB  
ALONG WITH SOME SYSTEM RELATIVE ISENTROPIC LIFT ON THE 300K SURFACE  
IN TANDEM WITH THE AFOREMENTIONED MOISTURE COLUMN. WITH A  
LACK OF SUPPORT CURRENTLY ON SATELLITE AND RADAR AND LIGHT NATURE  
EXPECTED...HAVE OPTED TO STICK WITH THE SILENT 10 TO 14 PERCENT  
POPS. HOWEVER...WILL ADD CHANCE FOR SPRINKLES AS EVEN LAST NIGHTS  
SYSTEM OVER PERFORMED WITH A FEW AREAS SEEING A FEW HUNDREDTHS OF  
AN INCH. LOWS TONIGHT WITH CLOUDS INCREASING WILL RANGE FROM MIDDLE  
40S EAST TO LOWER 50S WEST.  
 
EXPECT MAIN SURFACE FRONT WITH WIND SHIFT TO MOVE THROUGH MID  
MORNING TO EARLY AFTERNOON SATURDAY WITH CLEARING IN ITS WAKE  
THROUGH THE AFTERNOON HOURS. HIGHS WILL GENERALLY BE IN THE LOW TO  
MID 60S WITH SLIGHTLY COOLER AIR INFILTRATING THE NORTH IN THE  
AFTERNOON ONCE FLOW COMES AROUND OFF THE LAKE.  
 

 
   
LONG TERM
 
(SATURDAY NIGHT THROUGH FRIDAY)  
ISSUED AT 357 PM EDT FRI OCT 24 2014  
 
A STRONG UPPER LEVEL TROF WILL MOVE ACROSS THE CONUS EARLY NEXT WEEK  
AND IS EXPECTED TO BRING A GOOD CHANCE FOR RAIN TO THE FORECAST AREA  
BEGINNING MONDAY NIGHT. THE GFS AND ECMWF APPEAR TO HAVE A GOOD  
HANDLE ON THE INITIALIZATION AND EARLY VERIFICATION OF THE TRACK OF  
THIS SYSTEM THAT THIS AFTERNOON WAS WELL OFF THE WEST COAST OF NORTH  
AMERICA. THE GFS AND ECMWF THROUGH TUESDAY ALSO HAVE HAD REASONABLE  
RUN TO RUN CONSISTENCY...SO HAVE CONTINUED HIGH CHANCE OR LIKELY  
RAIN CHANCES TUESDAY. HAVE ADDED A SLIGHT CHANCE FOR THUNDER TUESDAY  
GIVEN VIGOROUS UPPER AIR SUPPORT...SUFFICIENT MOISTURE AND ADEQUATE  
LOW LEVEL FORCING ASSOCIATED WITH THE FRONT. AHEAD OF THIS SYSTEM...  
RAISED HIGHS OVER NORTHEAST AREAS MONDAY...WITH AFTERNOON TEMPS  
REACHING 72F TO 76F OVER ALL LAND AREAS EXCEPT VERY CLOSE TO LAKE  
MICHIGAN. OTHERWISE...MUCH COOLER AIR WILL SPREAD INTO THE AREA LATE  
IN THE WEEK. THE GFS AND ECMWF DIVERGE SIGNIFICANTLY...WITH THE GFS  
NOW COLDER THAN THE ECMWF AT 850 MB SATURDAY MORNING WITH A -10C.  
THEREFORE...TRENDED HIGHS DOWN A LITTLE FRIDAY IN LINE WITH THE  
LATEST ECMWF AND GFS LONG TERM GUIDANCE.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)  
ISSUED AT 125 PM EDT FRI OCT 24 2014  
 
SKIES BEGINNING TO PARTIALLY CLEAR THIS AFTERNOON WITH SUBSIDENCE  
BEHIND DEPARTING WEAK SHORT WAVE. EXPECT CONDITIONS TO TREND TO  
VFR THIS AFTERNOON. ANOTHER WEAK SHORT WAVE WILL APPROACH AGAIN  
TONIGHT WITH SIMILAR TIMING AS LAST NIGHT. THIS WAVE LOOKS TO HAVE  
A SLIGHTLY DEEPER MOISTURE PLUME BUT DYNAMICS NOT AS STRONG. THERE  
DOES APPEAR TO BE A NARROW WINDOW OF LIFT AND MOISTURE ALONG WEAK  
LOW LEVEL BOUNDARY THAT MAY ALLOW FOR A FEW SPRINKLES OR LIGHT  
SHOWERS. REGARDLESS...TAFS WILL HAVE MVFR CIGS AND VIS WITH MOIST  
LOWER LEVELS AS THIS WAVE APPROACHES. EXPECT SAT MORNING TO REMAIN  
CLOUDY AGAIN WITH MIXING AND CLEARING FOLLOWING MAIN FRONT BY  
AFTERNOON.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
MI...NONE.  
OH...NONE.  
LM...NONE.  

 
 

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