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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 050242
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
942 PM EST WED DEC 4 2013

.SYNOPSIS...
A COLD FRONT WILL PUSH EAST ACROSS THE REGION LATE TONIGHT THROUGH
THURSDAY. SEVERAL WAVES OF LOW PRESSURE MOVING ALONG THE FRONT
WILL RESULT IN WIDESPREAD PRECIPITATION THROUGH THE END OF THE WORK WEEK.
AS COLD AIR MOVES IN BEHIND THE FRONT...PRECIPITATION WILL
TRANSITION FROM RAIN TO A WINTRY MIX AND THEN TO SNOW LATE
THURSDAY NIGHT THROUGH FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
A SOUTHERLY LOW LEVEL FLOW WILL PERSIST THROUGH TONIGHT AHEAD OF
AN APPROACHING COLD FRONT. THE COMBINATION OF CONTINUED MOISTURE
ADVECTION AND INCREASING LOW LEVEL CONVERGENCE ALONG THE COLD
FRONT WILL RESULT IN AN INCREASING CHANCE OF SHOWERS OVERNIGHT.
DEVELOPING RADAR ECHOES OVER INDIANA SUPPORT THIS. IN WAA PATTERN
AHEAD OF THE COLD FRONT...DO NOT EXPECT TEMPERATURES TO FALL OFF
ALL THAT MUCH OVERNIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
THE COLD FRONT WILL PUSH THROUGH OUR AREA DURING THE DAY ON
THURSDAY AND SHOULD BE SITUATED JUST TO OUR SOUTHEAST BY 00Z FRI.
A SERIES OF SURFACE WAVES WILL RIDE EAST ALONG THE FRONT THURSDAY
INTO FRIDAY AND WITH COLD AIR SPILLING IN FROM THE NORTHWEST
BEHIND THE FRONT...WE WILL END UP WITH AN EXTENDED PERIOD OF
DECENT FRONTOGENETIC FORCING THURSDAY NIGHT THROUGH FRIDAY.
FURTHERMORE...AS THE LOW LEVELS COOL OFF WE WILL TRANSITION OVER
TO SNOW ACROSS THE NORTHWEST LATER THURSDAY NIGHT...WORKING DOWN
ACROSS THE REMAINDER OF OUR FA THROUGH THE DAY ON FRIDAY. THE 12Z
NAM HAS TRENDED A LITTLE COOLER AND IS NOW TRYING TO BRING THE
COLD AIR IN A LITTLE FASTER THAN THE REMAINING MODELS INCLUDING
THE 12Z GFS. THIS MAY BE A LITTLE ON THE FAST SIDE...BUT MODELS
TYPICALLY HAVE A DIFFICULT TIME HANDLING LOW LEVEL COLD AIR. AS A
RESULT...DO NOT WANT TO COMPLETELY DISMISS THE NAM AND WILL GO
WITH MORE OF A GFS/NAM BLEND FOR THIS FORECAST CYCLE.

AS THE INITIAL WAVE MOVES ALONG THE FRONT...EXPECT FAIRLY
WIDESPREAD PRECIPITATION THURSDAY MORNING. MARGINAL INSTABILITIES
ACROSS OUR EAST COULD RESULT IN AN ISOLATED THUNDERSTORM...BUT
THINK CHANCE IS LOW ENOUGH TO LEAVE MENTION OUT OF THE FORECAST.
WE COULD THEN GET INTO A BIT OF A BREAK THURSDAY AFTERNOON BEFORE
THE NEXT WAVE ARRIVES THURSDAY EVENING. THIS WILL ALLOW FOR
PRECIPITATION TO OVERSPREAD THE AREA FOR THURSDAY NIGHT. FORECAST
SOUNDINGS ARE SUGGESTING A CHANGEOVER TO SNOW ACROSS OUR NORTHWEST
AFTER MIDNIGHT. AS THE LOW LEVEL COLD AIR CONTINUES TO SAG IN
THROUGH THE DAY ON FRIDAY...EXPECT PCPN TO CHANGE OVER TO SNOW
ACROSS ALL BUT OUR FAR SOUTHEAST THROUGH FRIDAY AFTERNOON.
FORECAST SOUNDINGS ARE INDICATING AT LEAST A BRIEF TRANSITION PERIOD
OF A WINTRY MIX WITH SLEET AND POSSIBLY FREEZING RAIN...ESPECIALLY
ACROSS SOUTHEAST PORTIONS OF OUR FA. THE DURATION OF THIS IS
SOMEWHAT IN DOUBT THOUGH AND WILL ULTIMATELY DEPEND ON HOW FAST
THE COLD AIR WORKS IN. SURFACE TEMPERATURES ACROSS OUR SOUTHEAST
MAY VERY WELL REMAIN JUST ABOVE FREEZING INTO FRIDAY AFTERNOON
WHICH WOULD ALSO LIMIT THE FREEZING RAIN THREAT IN THOSE AREAS.

IT LOOKS LIKE ONE FINAL WAVE COULD WORK EAST ACROSS THE AREA
FRIDAY AFTERNOON INTO FRIDAY EVENING AS PRECIPITATION BECOMES ALL
SNOW ACROSS OUR FA. THE SNOW SHOULD THEN TAPER OFF FROM WEST TO
EAST OVERNIGHT FRIDAY AS THE WAVE PUSHES OFF TO THE EAST.
SNOWFALL ACCUMULATIONS WILL BE DEPENDENT ON HOW FAST THE
TRANSITION TO SNOW OCCURS AND HOW MUCH ANY SLEET CUTS INTO THE
SNOW ACCUMULATION. IT DOES LOOK LIKE THERE SHOULD BE A SOUTHWEST
TO NORTHEAST ZONE SOMEWHERE ACROSS OUR CENTRAL FA WHERE THE
COMBINATION OF COLDER AIR/HEAVIER PCPN WILL RESULT IN WARNING
CRITERIA ACCUMULATIONS....WITH 4 TO 6 INCHES POSSIBLE ALONG AND
JUST NORTHWEST OF THE I-71 CORRIDOR. SOUTHEAST OF THIS LINE...MIXED
PCPN COULD COMBINE WITH SNOWFALL AMOUNTS TO ALSO RESULT IN WARNING
CRITERIA. AS A RESULT WILL GO AHEAD AND ISSUE A WINTER STORM WATCH
FOR LATE THURSDAY NIGHT THROUGH FRIDAY NIGHT ACROSS MUCH OF OUR
AREA. OUR NORTHERN AREAS HAVE HIGHER WARNING CRITERIA SO WILL
LEAVE SOME OF OUR NORTHERN COUNTIES OUT OF THE WATCH AS THEY WILL
LIKELY BE IN MORE OF AN ADVISORY TYPE SITUATION.

THE OTHER CONCERN IS HEAVY RAIN AS PWS ARE FORECAST TO PUSH UP INTO
THE 200 TO 250 PERCENT OF NORMAL RANGE. WITH AN EXTENDED PERIOD
OF GOOD MOISTURE ADVECTION...LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE. FFG VALUES ARE SOMEWHAT ON THE HIGHER SIDE FOR THIS TIME
OF YEAR...WITH 3 HOUR FFG VALUES GENERALLY IN THE 1.5 TO 2.5 INCH
RANGE. BETWEEN THIS AND THE FACT THAT THE HEAVIEST RAIN THREAT
ACROSS OUR SOUTHEAST IS MORE IN THE THURSDAY NIGHT TO FRIDAY
PERIOD...WILL HOLD OFF ON ANY FFA HEADLINES ATTM.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
COLD AIR OVER THE REGION WILL BE PULLED IN ON SATURDAY AS HIGH
PRESSURE NOSES INTO THE WESTERN OHIO VALLEY FROM THE NORTHERN
PLAINS. LOW PRESSURE WILL DEVELOP AND STRENGTHEN OVER THE GULF
STATES AND THEN MOVE NORTHEAST TO THE OHIO VALLEY. THIS SYSTEM WILL
OVERSPREAD RAIN INTO KENTUCKY AND SOUTHERN CWA EARLY SUNDAY AND PUSH
INTO THE REST OF OHIO AND INDIANA LATER SUNDAY. TEMPERATURES AT THIS
TIME WOULD BE SUPPORTIVE OF THIS RAIN TO FREEZE ON CONTACT WITH THE
COLDER GROUND.

RAIN AND FREEZING RAIN WILL WARM IN THE SOUTHEAST DURING THE LATE
DAY AND SUNDAY EVENING AS WARM AIR GETS PULLED IN AND THEN CHANGE
BACK TO SNOW AS ANOTHER ROUND OF VERY COLD AIR IS PULLED IN FROM THE
WEST BY DAYBREAK MONDAY.

MONDAY AND TUESDAY WILL BOTH SEE A VERY MINIMAL REBOUND ON DAYTIME
HIGHS AND THEN DROP INTO THE TEENS AND EVEN SINGLE DIGITS OVERNIGHT.

&&

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
CONDITIONS ARE VFR TO START. THAT WILL CHANGE TONIGHT AS A COLD
FRONT APPROACHING FROM THE WEST BRINGS SHOWERS WITH MVFR. A BREAK
IN PRECIPITATION AROUND 15Z WILL BE FOLLOWED BY MORE SHOWERS AROUND
19Z AS A WAVE OF LOW PRESSURE AND ASSOCIATED MOISTURE SURGE ALONG
THE FRONT. WINDS WILL SHIFT FROM SOUTH TO NORTHWEST AS THE FRONT
PROGRESSES ACROSS THE AREA.

OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE LIKELY THURSDAY.
IFR ON FRIDAY WITH PRECIPITATION TURNING WINTRY AND ACCUMULATING.
MVFR TO IFR CEILINGS AND VISIBILITIES WILL BE POSSIBLE AGAIN ON
SUNDAY IN WINTRY PRECIPITATION.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH LATE
     FRIDAY NIGHT FOR OHZ042-051>053-060>062-070.
     WINTER STORM WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY
     NIGHT FOR OHZ054-055-063>065-071>074-077>080.
KY...WINTER STORM WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY
     NIGHT FOR KYZ089>097.
IN...WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH LATE
     FRIDAY NIGHT FOR INZ050-058-059-066-073-074.
     WINTER STORM WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY
     NIGHT FOR INZ075-080.

&&

$$
SYNOPSIS...JGL
NEAR TERM...CONIGLIO/JGL
SHORT TERM...JGL
LONG TERM...FRANKS
AVIATION...CONIGLIO