FXUS61 KILN 290616
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
116 AM EST SUN NOV 29 2009

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL SLIDE OFF TO THE EAST...BUT WILL
CONTINUE TO CONTROL THE REGIONS WEATHER INTO EARLY SUNDAY. A COLD
FRONT WILL MOVE INTO THE OHIO VALLEY BRINGING RAIN TO THE REGION
SUNDAY AFTERNOON INTO MONDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MID LVL RIDGING IS FCST TO FLATTEN OVERNIGHT. SKIES WILL BE MAINLY
CLEAR WITH SOME INCREASING THIN CIRRUS LATE. ALTHOUGH A SFC SWRLY
GRADIENT WL CONTINUE TONIGHT...CLEAR SKIES HAVE ALREADY RESULTED IN
SOME DECOUPLING...LEADING TO A WIDE RANGE IN TEMPERATURES. CASE IN
POINT IS A 12 DEGREE DIFFERENCE BETWEEN KCMH AND KVTA AT 03Z.
LOCATIONS THAT HAVE ALREADY DECOUPLED SHOULD NOT DROP BELOW
30 DEGREES...WHILE OTHER LOCATIONS CURRENTLY IN THE MID AND 
UPPER 40S SHOULD DROP INTO THE 35 TO 40 DEGREE RANGE BY MORNING.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
IN SPLIT FLOW PATTERN THE FLOW OVER THE OHIO VALLEY TO BACK AHD OF
NRN STREAM TROF WHICH DIGS INTO THE UPR MS VLY/WRN GREAT LAKES ON
SUNDAY. ASSOCIATED SURFACE LOW TO TRACK THRU THE GREAT LAKES WITH
SOUTHWARD TRAILING COLD FRONT INTO WRN OHIO BY 00Z MONDAY AND
ACROSS ILN/S FA MONDAY NIGHT. AXIS OF FAVORABLE LOW LEVEL FORCING
TO DEVELOP INTO WEST CENTRAL OHIO SUNDAY AFTN AND THEN WORKS ACROSS
THE FA SUNDAY EVENING. WL CONTINUE CURRENT FCST TREND BRINGING CHC
POPS INTO WRN OHIO LATE SUN AFTN AND THEN INCREASE POPS SUNDAY EVENING
TO LKLY AND CATEGORICAL. HAVE TRENDED SUNDAYS HIGHS A LTL COOLER THAN
MAV GUID.

DUE TO THE PROGRESSIVE NATURE OF THIS SYSTEM WILL TAPER OFF PRECIP
FROM NW TO SE MONDAY MORNING. MEAN UPPER LEVEL TROF TO PIVOT THRU
THE GREAT LAKES ON MONDAY. A FEW POST FRONTAL SHOWERS WILL BE POSSIBLE
ACRS THE NORTH MONDAY AFTN INTO MONDAY EVENING. THE NAM IS DRY WHILE
THE GFS AND ECMWF BRING PRECIP BACK ACRS THE NORTH. AT THIS TIME HAVE
ELECTED TO BRING SLIGHT CHC POPS AND UNDER INFLUENCE OF CAA HAVE INDICATED
A MIX OF RAIN/SNO SHOWERS. SFC RIDGING TO BUILD IN AS UPPER LEVEL FLOW
BECOMES NWRLY LATE MONDAY NIGHT INTO TUESDAY.

FOR THE PERIOD SUNDAY NIGHT THRU MONDAY NIGHT HAVE OPTED TO GO ON
THE COOL SIDE OF GUIDANCE ENVELOPE.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE TO BEGIN PERIOD WITH SEASONABLY COLD TEMPS. HIGH 
SHIFTS EAST BY WEDNESDAY. DEVELOPING LOW WILL SPREAD MOISTURE BACK 
INTO CWA WED AFTN AND WED NIGHT. MODELS HAVE BROUGHT SURFACE LOW 
CLOSER TO AREA AND THUS MORE QPF IS BEING FCST THAN PREVIOUS MODEL 
RUNS WHICH HAD A MORE EAST COAST SYSTEM. WILL BUMP POPS UP A BIT FOR 
NOW. TRANSITION TO CAA APPEARS CERTAIN BEHIND SYSTEM LATE
WEDNESDAY NIGHT AND THURSDAY BUT HOW FAST AND IF ANY LINGERING
MOISTURE IS BIG QUESTION MARK. SHOULD SEE SOME LIGHT SNOW SHOWERS
AND PERHAPS SOME LIGHT ACCUM IF MODEL FCST IS ACCURATE. WILL GO
WITH A CHANGE OVER FOR NOW AND KEEP CHC POPS GOING INTO THURSDAY
WITH CAA AND PROBABLY LAKE ENHANCED SNOW SHOWERS. HAVE LOWERED
PREVIOUS FCST MAX TEMPS FOR THURSDAY BASED ON NEW MODELS. MAY SEE
TEMPS FALL DURING THE DAY INSTEAD OF RISE BUT WILL LET LATER FCST
HANDLE THE DETAILS. MORE SNOW SHOWERS POSSIBLE INTO THURSDAY NIGHT
AND FRIDAY BUT WILL ONLY GO SLIGHT CHC POPS FOR NOW UNTIL MORE
CERTAIN. TEMPS AGAIN AT OR BELOW GUID WITH COLDEST AIR IN PLACE.
NEW MODELS SHOWING NEXT SYSTEM BY SATURDAY BUT WILL WAIT TO SEE
FURTHER MODEL GUIDANCE BEFORE INSERTING ANY PRECIP FOR NOW.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
COLD FRONT WILL CROSS THE OHIO VALLEY...REACHING TAF SITES BETWEEN
1Z AND 3Z. AHEAD OF THIS...CIGS WILL PRIMARILY BE VFR UNTIL JUST
BEFORE FROPA WHERE MVFR CIGS COME IN WITH THE MOISTENING COLUMN.
RAIN WILL LIKELY HOLD OFF UNTIL AFTER 0Z. WIND WILL GUST FROM THE
SSW TO OVER 20KT IN THE WARM SECTOR THIS AFTERNOON...TURN W AND SW
IMMEDIATELY POST FRONTAL WITH FEWER GUSTS...AND THEN KICK BACK IN
WITH A STRONGER SUSTAINED 12-14+KT AND HIGHER GUSTS WHEN THEY TURN
NW IN THE COLD AIR ADVECTION. THIS COLD AIR WILL LIKELY INTRODUCE
A MORE SOLID OVC MVFR DECK. THERE IS A CHANCE FOR IFR CIGS BLO
1KFT IN THE COLD AIR...BUT THERE SHOULD BE ENOUGH MIXING THAT THEY
STAY MVFR OVERNIGHT TOMORROW.

OUTLOOK...MVFR CIGS TO LINGER INTO MONDAY. 

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.

&&

$$
SYNOPSIS...HICKMAN
NEAR TERM...HICKMAN
SHORT TERM...AR
LONG TERM...
AVIATION...FRANKS