FXUS61 KILN 250223
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
923 PM EST THU DEC 24 2009

.SYNOPSIS...
A STRONG SURFACE LOW WILL LIFT NORTH UP THE MISSISSIPPI VALLEY
TONIGHT...SENDING AN OCCLUDED FRONT ACROSS THE REGION ON CHRISTMAS
DAY. THE LOW WILL MEANDER IN THE VICINITY OF IOWA CHRISTMAS DAY
AND SATURDAY...BEFORE LIFTING EAST INTO THE GREAT LAKES ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
SEVERAL CONCERNS THIS EVENING...BUT OVERALL FORECAST IS ON TRACK
WITH MINOR ADJUSTMENTS TO SPEED UP RAIN ARRIVAL A BIT IN THE
SOUTH/WEST...AND BUMP WINDS UP LATE. 

990MB CYCLONE NOW DEEPENING QUICKLY OVER SRN MO AS PHASING OF
ENERGY IS OCCURRING OVER THE CENTRAL CONUS. 25.00Z RUC HAS GOOD
HANDLE ON THIS...AND ANOMALOUS 70-80KT SELY LOW LEVEL JET OVER
AL/TN BRINGING COPIOUS MOISTURE NORTHWARD IN A HURRY THIS EVENING.
PRECIPITABLE WATER OFF THE KILN 25.00Z SOUNDING ALREADY 180
PERCENT OF NORMAL WITH LOWER MS VALLEY RAOBS ALL CONTAINING
175-200 PERCENT NORMAL. AS LOW PIVOTS NORTH INTO NRN MO AND SERN
IA BY SUNRISE...LOW LEVEL JET ON THE SERN QUAD OF THE CYCLONE WILL
SWING NORTHEAST AND FOCUS INTENSE MOISTURE TRANSPORT INTO THE OHIO
VALLEY. THIS SHOULD CONTINUE TO PROMOTE DEVELOPMENT OF RAIN BANDS
ON THE ERN SIDE /GRADIENT/ OF THE MOISTURE TRANSPORT REGION...AN
AREA ALSO RIPE WITH ISENTROPIC /290-300K/ ASCENT STRONG Q/G
FORCING. GIVEN THE LOW WILL BE 985MB...AND STRONG GRADIENT OVER
OHIO BY 12Z...WENT AHEAD AND BUMPED UP SUSTAINED WINDS OVERNIGHT
IN MOST LOCATIONS. STILL DON/T THINK A WIND ADVISORY IS
NEEDED...THANKS TO THE VERY STRONG INVERSION WHICH SHOULD KEEP
HIGH GUSTS ALOFT ESPECIALLY CONSIDERING WARM ADVECTION/LIFT IN THE
LOWEST 1-2KM. INITIAL RAIN BAND JUST INCHING INTO FAR SWRN CWA
NOW...SO ADJUSTED RAIN WORDING/GRIDS IN THESE AREAS...AND STILL
LOOK FOR STRONGEST PUSH OF RAIN OVERNIGHT FROM SSW TO NNE.
TEMPERATURES HANGING TOUGH IN THE MID 30S BUT STRONG WAA WILL WIN
OUT IN TIME AND SHOULD SEE A STEADY OR SLOWLY RISING SCENARIO
OVERNIGHT. 

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
12Z MODELS ARE IN GOOD AGREEMENT...PLACING THE SFC LOW IN NE MO
BY 12Z FRI. OCCLUDED FRONT WILL LIFT NORTHEAST ACROSS THE FA FRI.
GFS/ECMWF/CANADIAN ARE A LITTLE QUICKER WITH THE FROPA THAN THE
NAM/UKMET. LEANED TOWARDS THE GFS/EC TIMING. AS OCCLUDED FNT LIFTS
NE ACRS FA...IT SHOULD BRING AN END TO THE WIDESPREAD RAIN. THERE
WILL BE A CHANCE OF LINGERING R BEHIND THE FNT...WITH PLENTY OF
LOW LEVEL MOISTURE AND WEAK LOW LEVEL CONVERGENCE. MIGHT SEE SOME
SNOW TRY TO MIX IN ACROSS THE NW COUNTIES IN THE AFTERNOON...BUT
LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED.

ALL MODELS ARE TRYING TO BRING A DRY SLOT IN FRI NGT...AS OCCLUDED
FNT CONTINUES TO LIFT N...SO DRIED OUT THE FA AFT MIDNIGHT. H5 AND
SFC LOW BEGIN TO KICK OUT THE MS VLY ON SAT. THIS WILL GIVE SOME
LIFT TO THE WRN AREAS...SO WILL NEED A SMALL POP. THE OVERALL
FLOW IS SW...SO THIS IS NOT FAVORABLE TO SHSN EVERYWHERE. AS THE
LOWS KICK E SAT NGT...CHC OF SHSN WILL INCREASE.

MAV/MET TEMP GUIDANCE WERE VERY SIMILAR...SO DIDNT STRAY VERY FAR.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
WITH THE GFS COMING IN LINE WITH THE ECMWF...SNOW SHOWERS WILL BE 
LIKELY SUNDAY DUE TO A POTENT SHORT WAVE THAT WILL DROP DOWN FROM 
THE WESTERN GREAT LAKES. MODEL QPF IS RATHER SKIMPY AS USUAL WITH 
THIS TYPE OF SYSTEM...BUT THERE IS THE POTENTIAL FOR LIGHT SNOW 
ACCUMULATIONS. A FEW SNOW SHOWERS MAY PERSIST ON MONDAY WITH A 
LITTLE HELP FROM LAKE MICHIGAN MOISTURE CARRIED BY A NORTHWEST 
FLOW.  

HIGH PRESSURE WILL PROVIDE DRY WEATHER AS IT TRAVELS ACROSS THE 
REGION TUESDAY AND WEDNESDAY. A COLD FRONT AND ASSOCIATED WAVE OF 
LOW PRESSURE WILL BRING A CHANCE OF SNOW NEXT THURSDAY.

TEMPERATURES WILL BE BELOW NORMAL THROUGH THE PERIOD WITH HIGHS IN 
THE 20 AND 30S AND LOWS IN THE TEENS AND 20S.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR CIGS WILL CONTINUE THROUGH THE EVENING BUT STRONG MOISTURE
TRANSPORT AND WARM ADVECTION ON NOSE OF STRONG LOW LEVEL JET IS
SENDING INITIAL RAIN BANDS NORTH THROUGH THE TN VALLEY RIGHT
NOW...AND THIS IS EXPECTED TO OVERSPREAD TAF SITES LATER THIS
EVENING WITH GENERALLY VFR LIGHT RAIN. STRONGER PUSH OF MOISTURE
COMES AFTER MIDNIGHT WITH A BAND OF MODERATE RAIN WHICH WILL TAKE
VSBYS/CIGS INTO MVFR CATEGORY. IN ADDITION...THE STRONG LOW LEVEL
JET /60KT AT 2KFT/ OUT OF THE SOUTHEAST...ON TOP OF EASTERLY WINDS
AT THE SFC WILL GENERATE THE THREAT FOR NON-CONVECTIVE LOW LEVEL
WIND SHEAR FOR MUCH OF THE OVERNIGHT INTO EARLY FRIDAY MORNING.
RAIN/SHOWERS AND MVFR CONDS EXPECTED TO CONTINUE WITH STRONG
SOUTHEAST WINDS ON FRIDAY MORNING BEFORE COLD FRONT SWINGS THROUGH
IN THE AFTERNOON...WITH A WIND SWITCH TO THE SOUTHWEST. THIS MAY
ALLOW CIGS TO RISE...BUT KEPT A MORE PESSIMISTIC VIEW PER NAM-WRF
SOUNDINGS AND GFS LAMP DATA. CIGS WILL LIKELY STAY MVFR THROUGH
FRIDAY NIGHT.

OUTLOOK...MVFR CIGS POSSIBLE SATURDAY INTO MONDAY. MVFR/IFR
VSBYS POSSIBLE SUNDAY INTO SUNDAY NIGHT.

&&

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

&&

$$
SYNOPSIS...SITES
NEAR TERM...BINAU
SHORT TERM...SITES
LONG TERM...CONIGLIO
AVIATION...BINAU