000
FXUS61 KILN 240244
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
944 PM EST MON NOV 23 2009

.SYNOPSIS...
A WEAK UPPER SHORTWAVE OVER THE OHIO VALLEY WILL MOVE EAST OF THE
REGION THIS EVENING. A STRONGER UPPER TROUGH WILL DIG INTO THE
MIDWEST ON TUESDAY AND WEDNESDAY...FOLLOWED BY AN EVEN DEEPER
SYSTEM WEDNESDAY NIGHT AND THURSDAY.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AREA OF CLOUDS ACROSS NRN PORTION OF THE FA...THAT HAD BEEN VFR
SAW CIGS DROP TO IFR AS THE COLUMN COOLED. THIS HAS SLOWED THE NE
PROGRESSION OF THE CLEARING. EXPECT THE ST TO EXPAND OVERNIGHT AS
THE LOW LEVELS COOL. LOOKS MORE LIKE A ST SITUATION THAN A DENSE
FOG ONE TONIGHT. SO WENT WITH MOSTLY CLOUDY OR CLOUDY
SKIES...EXCEPT IN THE W WHERE IT CLEARED. WENT BECOMING MOSTLY
CLOUDY THERE.

TD ARE STILL IN THE MID TO UPPER 40S IN THE E. WITH THE
CLOUDS...DONT SEE THEM FALLING A LOT OVER NIGHT. RAISED TEMPS IN
THE E 4 TO 5 DEGREES. SPOTS IN THE W HAVE COOLED OFF DUE TO THE
CLEARING...SO LOWERED TEMPS A BIT THERE.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
BRIEF UPPER RIDGING WILL MOVE OVERHEAD ON TUESDAY...THOUGH ENOUGH
LOW LEVEL MOISTURE SHOULD STAY BEHIND TO KEEP SKIES PARTLY TO
MOSTLY CLOUDY. 

DEEPENING SHORTWAVE DIGGING INTO THE MIDWEST WILL LEAD TO
CYCLOGENESIS OVER NORTHERN ILLINOIS TUESDAY NIGHT. SFC LOW WILL
TRACK INTO WESTERN MICHIGAN BY 12Z WEDS AND WILL PUSH A WEAK
FRONTAL BOUNDARY ACROSS THE CWA WEDS MORNING. NAM CONTINUES TO BE
THE SLOW OUTLIER WITH THE TIMING OF THIS SYSTEM...SO TRENDED
TOWARD A GFS/ECMWF BLEND WHICH ARE IN REASONABLE AGREEMENT. WEAK
ISENTROPIC LIFT WILL SPREAD IN AHEAD OF THE FRONT WEDS NIGHT...SO
KEPT CHANCE POPS GOING AREA WIDE TUES NIGHT AND EARLY WEDS...WITH
HIGHEST POPS ACROSS THE NORTH IN CLOSER PROXIMITY TO BEST UPPER
LEVEL FORCING. LINGERING ELEVATED ISENTROPIC LIFT MAY PRODUCE A
FEW LIGHT SHOWERS BEHIND THE FRONT WEDS EVENING. DEEPER SYSTEM
WILL DIG INTO THE MIDWEST WEDS NIGHT WITH ANOTHER WEAK FRONT
PUSHING INTO THE CWA BY 12Z THURS. THIS SYSTEM WILL BE MORE
MOISTURE STARVED...SO KEPT POPS LIMITED TO LOW-END CHANCE THROUGH
12Z THURS.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
LONG RANGE MODELS ARE FAIRLY SIMILAR IN TERMS OF SYNOPTIC POSITIONS 
THROUGH AT LEAST SUNDAY. HAVE MAINLY RELIED ON A 00Z/12Z GFS BLEND 
THROUGH THIS PERIOD.

MODELS CONTINUE TO DEPICT A DIGGING UPR LVL CLOSED LOW WHICH IS 
FORECAST TO DROP FROM THE NRN PLAINS TO THE WESTERN GREAT LAKES BY 
THURSDAY.  THIS FEATURE WILL PUSH ANOTHER COLD FRONT THROUGH THE 
REGION THURSDAY MORNING. WILL MAINTAIN A 30 TO 50 PERCENT CHANCE FOR 
SHOWERS.

FOR THE PERIOD THURSDAY NIGHT INTO FRIDAY...AS THE UPR LVL CLOSED 
LOW CONTINUES TO TREK EAST TOWARD THE EASTERN GREAT LAKES...IT WILL 
UNDERGO SOME DEEPENING. THIS WILL ALLOW THE ATMOSPHERE TO COOL AS 
WELL AS ADVECT COLDER AIR INTO OUR REGION. WRAP AROUND/LAKE INDUCED 
RAIN SHOWERS WILL MIX WITH SNOW SHOWERS THURSDAY NIGHT...BECOMING 
ALL SNOW SHOWERS BY FRIDAY MORNING. SOME DIURNAL HEATING ON FRIDAY 
WILL ALLOW THE SNOW TO MIX WITH OR CHANGE BACK TO RAIN DURING FRIDAY 
AFTN. PCPN WILL TAPER OFF FRIDAY NIGHT. SHOWERS THURSDAY NIGHT INTO 
FRIDAY NIGHT WILL BE SCATTERED AND LIGHT IN NATURE. ANY SNOW THAT 
FALLS WILL HAVE A HARD TIME ACCUMULATING DUE TO THE LIGHT NATURE OF 
THE SHOWERS AND A FAIRLY WARM GROUND FOR LATE NOVEMBER. LITTLE TO NO 
SNOW ACCUMULATION IS EXPECTED ATTM.

AFOREMENTIONED DEEPENING UPR LVL CLOSED LOW IS FORECAST TO PIVOT NE 
INTO THE NEW ENGLAND REGION BY SATURDAY. THIS WILL ALLOW HIGH 
PRESSURE AT THE SFC AND ALOFT TO BUILD INTO THE GREAT LAKES AND OHIO 
VALLEY FROM THE WEST. HIGH PRESSURE WILL MOVE EAST OF THE REGION ON 
SUNDAY...ALLOWING A COLD FRONT TO DROP FROM THE NW TOWARD OUR AREA 
LATE IN THE DAY. 

FOR MONDAY...HAVE KEPT CONTINUITY BY ALLOWING THE COLD FRONT TO 
SLOWLY DROP SOUTH OF THE OHIO RIVER. LATEST OPERATIONAL MODELS ARE 
STILL UNCERTAIN ABOUT THE WEATHER PATTERN INTO NEXT WEEK AS DEPICTED 
BY THEIR RUN TO RUN INCONSISTENCY.

HIGH TEMPERATURES WILL FALL TO BELOW NORMAL READINGS THURSDAY AND 
FRIDAY WITH A RECOVERY TO NEAR NORMAL TEMPERATURES OVER THE WEEKEND.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
H5 S/W PUSHING THRU THE FA IS ALSO PUSHING THE MID AND HIGH
LEVELS CLOUDS ASSOCIATED WITH IT OUT OF THE AREA. AREA OF CLEARING
HAS WORKED INTO THE SE IN/SW OH/NRN KY. EXPECT THIS DEEPER
MOISTURE TO PUSH NE OF THE TAFS BY 04Z.

LOW LEVELS REMAIN VERY MOIST. EXPECT ST TO EITHER FORM OR MOVE N
FROM KY AROUND 04Z. CIGS ARE EXPECTED TO LOWER IN MVFR RANGE.
EXPECT SOME SCT IFR BR ALSO.

MODELS ARE INDICATING THAT MIXING WILL OCCUR AFT 14Z AND THAT
CIGS AND VSBYS SHOULD BECOME VFR BY LATE MORNING.

OUTLOOK...MVFR CIGS/VSBYS POSSIBLE TUESDAY NIGHT INTO FRIDAY.

&&

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

&&

$$
SYNOPSIS...HAWBLITZEL
NEAR TERM...SITES
SHORT TERM...HAWBLITZEL
LONG TERM...HICKMAN
AVIATION...SITES