FXUS61 KILN 260101
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
801 PM EST FRI DEC 25 2009
.SYNOPSIS...
INTENSELY STRONG SYNOPTIC LOW PRESSURE SYSTEM IN THE UPPER MIDWEST WILL
WEAKEN AS IT MOVES INTO THE GREAT LAKES REGION ON SATURDAY. AS IT
MOVES NORTHEAST INTO CANADA IT WILL SLOWLY LOSE ITS PUNCH BY LATE
SUNDAY. IN THE OHIO VALLEY...THE LEFTOVER UPPER LEVEL TROUGH WILL
CROSS ON SUNDAY NIGHT...LIMITING ANY SIGNIFICANT CHANCE FOR
PRECIPITATION AFTER THIS TIME.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
UPDATED THE FORECAST TO HANG ON TO SHOWERS IN CENTRAL OHIO THROUGH
LATE EVENING AS FINAL BAND OF SHOWERS HAS SLOWED AS IT HAS BEGUN
TO WEAKEN. EXPECT THIS ACTIVITY TO BE MOSTLY DIMINISHED/SHIFTED
EAST BY 10 PM OR SO. ALSO WATCHING LARGE AREA OF VERY LIGHT
SNOW/FLURRIES OVER CNTL IL/WRN IN BUT TRAJECTORY IS TO TAKE THIS
MORE NORTHEAST INTO NERN IN/NW OHIO. MENTIONED FLURRIES IN
WESTERN/NRN CWA AND WILL WATCH THIS A FEW MORE HOURS AND SEE
WHETHER WE/LL NEED A HIGHER COVERAGE WORDING BUT NOT EXPECTING
ACCUMULATIONS. TEMPS/WINDS LOOKED ROUGHLY ON TRACK.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
CANNOT DEFINITVELY RULE OUT A STRAY SNOW SHOWER ON
SATURDAY...PARTICULARLY IN NWRN FCST AREA CLOSER TO THE UPPER
LEVEL DYNAMICS. OHIO VALLEY STAYS ON THE WARM SECTOR OF THIS
LOW...LIMITING ANY EXTREME TEMPERATURE FALLS ADVECTING IN FROM
SUCH AN ENERGETIC SYSTEM. THE CHANCE FOR SNOW WILL INCREASE ON
SUNDAY AFTERNOON AS THE UPPER LEVEL AXIS OF THE LEFTOVER LOW
CROSSES W-E THROUGH OHIO VALLEY...FOLLOWING WHAT IS STILL A CUTOFF
LOW FROM LAKE MICH TO ERN LERI. AFTER THIS TIME...UPPER LEVEL
SUPPORT IS UNFAVORABLE OUTSIDE OF IMMEDIATE GREAT LAKE INFLUENCES
AND PRECIP IN REMAINDER OF OHIO SHOULD DROP OFF TO NOTHING.
TEMPERATURES WILL RETURN TO MORE SEASONAL VALUES WITH HIGHS IN THE
MID TO UPPER 30S AND LOWS STARTING OFF AROUND 30 TONIGHT...
DROPPING TO AROUND 20 BY SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
A FEW SNOW SHOWERS MAY OCCUR ACROSS NORTHERN COUNTIES ON MONDAY
IN A WEST NORTHWEST FLOW BEHIND A STRONG SHORT WAVE. SOME MOISTURE
FROM LAKE MICHIGAN MAY ENTER THE PICTURE. SKIES WILL BE MOSTLY
SUNNY ON TUESDAY AS HIGH PRESSURE TRAVELS THROUGH OHIO. CLOUDS
WILL INCREASE ON WEDNESDAY AHEAD OF AN APPROACHING COLD
FRONT...THOUGH PRECIPITATION MAY NOT SPREAD IN AS QUICKLY AS
SUGGESTED BY THE ECMWF. WENT WITH A CHANCE OF SHOW SHOWERS
THURSDAY ACCOMPANYING FRONTAL PASSAGE. LATEST RUN OF ECMWF HAS
HIGH PRESSURE MOVING IN NEXT FRIDAY SO WENT WITH A DRY FORECAST.
TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE PERIOD WITH HIGHS
MAINLY IN THE 30S AND LOWS IN THE TEENS AND 20S.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
MAIN TREND IN NEW 00Z TAFS WAS TO INCREASE CIGS A LITTLE SOONER
INTO VFR RANGE...WITH MIX OF MVFR/VFR CIGS ALREADY SPREADING INTO
CVG THANKS TO DRYING SOUTHWESTERLY FLOW OF MODEST STRENGTH.
UPSTREAM OBSERVATIONS SUPPORT A PRETTY GOOD PROBABILITY OF GOING
VFR FROM SOUTHWEST TO NORTHEAST ACROSS OUR TAF SITES THROUGH THE
NIGHT...SO TRENDED THE FORECAST THIS WAY. KEPT THE GUSTY WINDS
THROUGH THE NIGHT PER NAM-WRF BUFR SOUNDINGS SHOWING STEEP LAPSE
RATES AND CONTINUED GRADIENT AROUND WEAKENING IOWA WINTER STORM.
RESIDUAL RAIN NEAR CVG/LCK WILL BE DONE BY 03Z...WITH ANY FLURRIES
OVERNIGHT NOT EXPECTING TO REDUCE VSBYS. ALSO WATCHING MORE RECENT
TRENDS OF EVEN SOME SCATTERING OUT OF THE CIGS ACROSS TN/KY...AND
THIS MAY /BRIEFLY/ HAPPEN AT CVG/CMH/LUK/LCK.
OUTLOOK...MVFR CIGS POSSIBLE SUNDAY INTO MONDAY AND AGAIN ON
WEDNESDAY. MVFR/IFR VSBYS POSSIBLE SUNDAY INTO SUNDAY NIGHT.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...BINAU
SHORT TERM...FRANKS
LONG TERM...CONIGLIO
AVIATION...BINAU
