414 
FXUS63 KIWX 100801
AFDIWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
401 AM EDT FRI OCT 10 2014

.SYNOPSIS...
ISSUED AT 100 AM EDT FRI OCT 10 2014

AREAS OF LIGHT RAIN ASSOCIATED WITH A FRONT ARE EXPECTED TO LINGER
TODAY INTO TONIGHT OVER THE SOUTHERN HALF OF ILLINOIS INTO SOUTHERN
OHIO. OTHERWISE...SKIES SHOULD BE CLEAR TO PARTLY CLOUDY OVER THE
NORTHERN HALF OF THE REGION. HIGHS TODAY WITH BE IN THE MID TO
UPPER 50S. LOWS TONIGHT WILL DIP INTO THE 30S NORTH AND 40S SOUTH
WITH PATCHY FROST POSSIBLE FROM LOWER MICHIGAN INTO NORTHERN 
INDIANA.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM EDT FRI OCT 10 2014

THE FRONT HAD MOVED SOUTH OF THE OHIO RIVER EARLY THIS MORNING... 
HOWEVER...SOME LINGERING AREAS OF LIGHT RAIN EXTENDED WELL NORTH OF 
THE FRONT IN A AREA OF WEAK LIFT ACROSS CENTRAL INDIANA. THE 12KM 
NAM APPEARS TO HANDLE THIS SYSTEM REASONABLY WELL AND IS PREFERRED 
OVER THE GFS WHICH DEVELOPS LIGHT RAIN TOO FAR NORTH OF THE FRONT. A 
NAM CROSS SECTION DEPICTS INCREASING SUBSIDENCE OVER THE FORECAST 
AREA AS COOL AND DRY AIR CONTINUES TO SPREAD INTO THE WESTERN GREAT 
LAKES REGION TODAY. NOT MUCH SUPPORT FROM THE THE UPPER LEVEL JET IS 
EXPECTED...THEREFORE...KEPT THE FORECAST DRY THROUGH TONIGHT. GIVEN 
AN OPTIMUM NIGHT OF RADIATIONAL COOLING WITH LIGHT WINDS...CLEAR 
SKIES AND A COOL AND DRY AIRMASS...LOWS TONIGHT SHOULD DIP WELL 
DOWN INTO THE 30S WITH PATCHY FROST POSSIBLE FROM LOWER MICHIGAN 
INTO NORTHERN INDIANA AND NORTHWEST OHIO.

&&

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 356 AM EDT FRI OCT 10 2014

LONG TERM FORECAST REMAINS INTERESTING WITH VERY STRONG STORM SYSTEM 
STILL EXPECTED EARLY NEXT WEEK. POSSIBILITY OF HEAVY RAINFALL AND
ANY SEVERE WEATHER REMAIN THE PRIMARY CONCERNS. 

HIGH PRESSURE WILL BE MOVING ACROSS THE GREAT LAKES AND LOCAL AREA 
SATURDAY AND TO THE EASTERN LAKES ON SUNDAY. DESPITE PLENTY OF SUN 
ON SATURDAY...TEMPERATURES WILL ONLY CLIMB INTO THE UPPER 50S WITH 
LIGHT EASTERLY LOW LEVEL FLOW. LIGHT WINDS ACROSS THE EASTERN HALF 
OF THE AREA SAT NIGHT WILL ALSO ALLOW TEMPS TO FALL BACK INTO THE 
MIDDLE 30S WITH ANOTHER CHANCE FOR PATCHY FROST EARLY SUNDAY 
MORNING. 

MODELS HAVE CONTINUED TO SLOW AND WEAKEN INITIAL LEAD SHORT WAVE AND 
MOISTURE ADVECTION FOR SUNDAY. LATEST GUIDANCE INDICATES MOSTLY 
CLEAR SKIES TO START THE DAY WITH INCREASING CLOUDS BY AFTERNOON. 
WEAK LIFT ASSOCIATED WITH SUBTLE SHORT WAVE AND THETA E SURGE MAY 
STILL BE ENOUGH TO GENERATE A FEW LIGHT SHOWERS IN THE AFTERNOON SO 
WILL CONTINUE WITH LOW CHANCE POPS BUT HAVE ADJUSTED TIMING TO AFTER 
18Z AND LEFT THE MORNING HOURS DRY. MOISTURE FEED WILL CONTINUE 
SUNDAY NIGHT INTO MONDAY AS SOUTHERLY FLOW INCREASES WITH DEEPENING 
LONG WAVE TROUGH IN THE PLAINS. MODELS STILL SHOWING A VERY STRONG 
120+ KNOT UPPER LEVEL JET...CURRENTLY OVER THE NORTH PACIFIC... 
DIGGING INTO THE BASE OF THIS TROUGH. AN OPEN GOMEX WILL ALLOW PWATS 
IN EXCESS OF 1.5 INCHES TO MOVE IN SUPPORTING HEAVY RAINFALL 
POTENTIAL. GFS40 SHOWING VERY STRONG WIND FIELDS WITH 850MB LOW 
LEVEL JET IN EXCESS OF 60 KNOTS MONDAY AND MONDAY NIGHT. THIS 
LEADING TO IMPRESSIVE 0-1KM SHEAR VALUES AROUND 60 KNOTS WITH 
VEERING LOW LEVEL PROFILE. SEVERE WEATHER IS A POSSIBILITY AS THIS 
IS THE TYPICAL SETUP WE SEE FOR OUR SECONDARY FALL SEASON EPISODES 
OF HIGH SHEAR LOW CAPE ENVIRONMENTS LEADING TO QLCS STORMS AND LOW 
TOPPED SUPERCELLS. HOWEVER...CURRENT MODEL CAPES REMAIN AOB 500 J/KG 
AND TIMING OF FRONT AND POTENTIAL CONVECTIVE LINE NOT IDEAL WITH 
INDICATIONS IT COULD BE MID TO LATE EVENING OR EVEN OVERNIGHT MONDAY 
BEFORE MAIN LINE OF CONVECTION ARRIVES. THUS DETAILS REMAIN MURKY 
WITH STRONG JET ENERGY STILL OVER THE PACIFIC SO WILL CONTINUE TO 
MONITOR THIS. CERTAINLY WORTHY OF REMAINING AWARE OF POTENTIAL 
THROUGH THE HOLIDAY WEEKEND.  

TIMING ISSUES WITH FRONTAL PASSAGE AND EVENTUAL DRYING CONTINUE 
ESPECIALLY IN LIGHT OF LATEST 00Z/10 ECMWF WHICH NOW CLOSES OFF 
UPPER LOW RIGHT OVER THE LOCAL AREA AND THEN RETROGRADES IT WEST. 
THIS IN RESPONSE TO STRONG DOWNSTREAM RIDGING AND VERY STRONG JET 
DYNAMICS ALOFT. WILL NOT MAKE ANY SIGNIFICANT CHANGES TO SUPERBLEND 
INIT UNTIL WE SEE A BIT MORE CONTINUITY IN MODELS. A FEW GFS 
ENSEMBLES DO SUPPORT A SLOWER PROGRESSION WHICH MAKES SENSE. 

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1253 AM EDT FRI OCT 10 2014

VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THIS FORECAST
PERIOD AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION. 


&&

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

$$

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


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