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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 100609
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
109 AM EST WED FEB 10 2010

.SYNOPSIS...
SURFACE LOW WILL TRACK FROM NORTHEAST OHIO TO CENTRAL LAKE ERIE
TONIGHT...WHILE A NEGATIVELY-TILTED UPPER TROUGH SWINGS THROUGH
THE OHIO VALLEY. HIGH PRESSURE WILL BUILD INTO THE OHIO AND
TENNESSEE VALLEYS LATE WEDNESDAY AND PERSIST THROUGH SATURDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
ARCTIC FRONT WAS QUICKLY MOVING EAST ACRS CENTRAL OHIO AND SOUTH
CENTRAL OHIO AND NORTHEAST KENTUCKY THIS EVENING. A BURST OF HEAVY
SNOW AND WIND GUSTS BETWEEN 30 TO 40 MPH WERE ACCOMPANYING THIS
FRONT. TEMPERATURES WILL DROP INTO THE 10 TO 15 RANGE BEHIND THE
FRONT.

MOISTURE IS STILL FORECAST TO WRAP AROUND LOW PRESSURE AS IT MOVES
TO CENTRAL LAKE ERIE BY MORNING. THIS MOISTURE WILL BE ASSOCIATED
WITH A SFC TROF AXIS. THIS WILL PROVIDE A SECONDARY AREA OF SNOW
LATE TONIGHT INTO WEDNESDAY. ADDITIONAL SNOW ACCUMULATIONS
OVERNIGHT WILL RANGE BETWEEN 1 AND 2 INCHES. WINDS WILL SHIFT TO
THE NORTHWEST LATE TONIGHT INTO WEDNESDAY...BRINGING WIND GUSTS
BETWEEN 30 AND 40 MPH. THIS WILL RESULT IN BLOWING AND DRIFTING OF
SNOW. WINTER STORM WARNING WILL CONTINUE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
LEADING EDGE OF WAA WILL BE ALIGNED WITH A LOW-LEVEL TROUGH
EXTENDING SOUTHWESTWARD FROM AFOREMENTIONED SFC LOW...WHICH WILL
BE OVER SE LAKE ERIE BY 12Z WEDS. CONVERGENCE ASSOCIATED WITH THE
LOW-LEVEL TROUGH AND THE NOSE OF AN INTENSIFYING LOW-LEVEL JET
WILL BE MORE THAN ADEQUATE FOR SNOW SHOWERS TO DEVELOP NEAR THE
SFC TROUGH. LIFT WILL BE ENHANCED BY LOW-LEVEL WARM AIR ADVECTION
ON THE BACK SIDE OF THE SURFACE COLD POCKET. IN ADDITION...MODELS
ARE HINTING AT AN AREA OF LOW-LEVEL FRONTOGENESIS NEAR THE SFC
TROUGH...JUST UNDERNEATH A ZONE OF NEGATIVE EPV NEAR 850 HPA...
WHICH IS THE RESULT OF A LOW-LEVEL TROWAL-LIKE FEATURE ON THE BACK
OF THE SFC COLD POCKET UNDERCUTTING COLD TEMPS ALOFT. IF THIS WERE
TO OCCUR THROUGHOUT A DEEP LAYER OF THE ATMOSPHERE...BANDED HEAVY
SNOW WOULD BE LIKELY. HOWEVER...THIS FORCING WILL ALL BE CONFINED
BELOW 700-HPA...WITH DEEP MOISTURE ONLY EXTENDING TO 600-HPA. THIS
MAKES IT TRICKY TO ASSESS THE POTENTIAL FOR ADDITIONAL SNOWFALL
ON WEDNESDAY. HOWEVER...AS UPPER COLD POCKET MOVES THROUGH...MAX
DENDRITIC GROWTH ZONE WILL DROP TO NEAR 850-800 HPA...SO THIS MAY
ALLOW FOR BURSTS OF HEAVY SNOW SHOWERS ASSOCIATED WITH SFC TROUGH
AND BACK EDGE DEPARTING COLD POOL. THIS ACTIVITY WOULD MOST
LIKELY MAKE IT TO ROUGHLY THE I-75 CORRIDOR BTWN 09Z AND 11Z...AND
INTO CNTRL OHIO BY 13Z-15Z. EXPECT SNOW ACCUMULATION OF 1 TO 2
INCHES WITH THIS ACTIVITY...THOUGH THERE MAY BE LOCALLY HIGHER
AMOUNTS IF SNOW SHOWERS GET HEAVY ENOUGH.

WHILE 1 TO 2 INCHES WOULD NOT NORMALLY BE ENOUGH TO KEEP A WARNING
GOING...THE SNOW SHOWER ACTIVITY WILL BE ACCOMPANIED BY INCREASING
NORTHWEST WINDS BEHIND THE SFC TROUGH...WHICH WILL GUST UP TO 40
MPH AT TIMES. COMBINED WITH SNOW ON THE GROUND...THIS WILL BRING
WIDESPREAD BLOWING SNOW TO MUCH OF THE AREA...ESPECIALLY TO
NORTHERN SECTIONS OF THE AREA WHERE SNOW ON THE GROUND REMAINS
POWDERY IN NATURE. IF SNOW SHOWERS BECOME HEAVY...WITH VSBYS BELOW
1/2 MILE...THE COMBINATION OF BLOWING SNOW AND FALLING SNOW MAY
LEAD TO OCCL SNOW SQUALLS WITH NEAR WHITE-OUT CONDITIONS. FOR
THIS REASON...WINTER STORM WARNING WILL CONTINUE AREA WIDE THRU
WEDS AFTERNOON.

MOST SNOW WILL TAPER OFF FROM WEST TO EAST THRU THE AFTERNOON BUT
THERE MAY BE SOME LINGERING SNOW SHOWERS THRU EARLY EVENING. WINDS
WILL CONTINUE TO GUST IN THE 25-35 MPH RANGE THROUGH LATE
AFTERNOON WHICH WILL CAUSE BLOWING SNOW PROBLEMS TO PERSIST. ANY
LINGERING SNOW SHOWERS AND WINDS WILL SUBSIDE AFTER DARK WEDS.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGH PRESSURE WILL BE WORKING INTO THE AREA FOR THE BEGINNING OF THE
PERIOD.  HIGH PRESSURE WILL STICK AROUND THE FA THROUGH SATURDAY
AFTERNOON.  THE GFS IS TRYING TO BRING A WEAK UPPER LEVEL
DISTURBANCE ACROSS SW PORTIONS OF THE AREA FRIDAY NIGHT.  HAVE LEFT
THIS OUT OF THE FA FOR NOW WITH THE GFS THE ONLY MODEL PICKING UP ON
THIS FEATURE.  MODELS START TO DIVERGE FOR THE LATE WEEKEND STORM
SYSTEM SATURDAY NIGHT INTO SUNDAY.  THE GFS IS FAR MORE PRONOUNCED
WITH THIS FEATURE WHILE THE ECMWF IS WEAKER.  HAVE INCREASED CHANCE
OF PRECIPITATION OVERNIGHT SATURDAY NIGHT INTO SUNDAY FOR NOW.
THERE HAS BEEN A LOT OF RUN TO RUN VARIABILITY WITH THIS SYSTEM AND
THEREFORE WILL HAVE TO CONTINUE TO MONITOR.  TEMPERATURES WILL BE
COLD ENOUGH FOR ALL SNOW WITH THIS SYSTEM.  SNOW WILL BEGIN TO TAPER
OFF ON MONDAY WITH HIGH PRESSURE BUILDING IN LATE IN THE PERIOD.
FOR TEMPERATURES GENERALLY WENT ON THE COOL SIDE OF GUIDANCE WITH
SNOW ON THE GROUND.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
H5 LOW IS E OF THE TAFS AND INTO NE KY. AS H5 LOW PULLS E AREA OF
WRAP AROUND SNOW IN INDIANA WILL WORK INTO THE TAFS. CIGS/VSBYS
ARE MVFR IN THE SN...WITH SOME ISOLATED IFR. WINDS ARE NOT REAL
STRONG HOWEVER...SO CUT BACK ON THEM FOR THE NEXT FEW HOURS. WINDS
SHOULD PICK UP AGAIN WHEN SECONDARY TROF SWINGS THRU AROUND 12Z.
EXPECT GUSTS OVER 30KT CAUSING MORE BLSN.

CYCLONIC FLOW AROUND SFC AND H5 LOWS WILL CONTINUE DURING THE
DAY...PULLING MOISTURE OFF LAKE MI. MVFR CIGS AND VSBYS WILL
AFFECT THE TAFS THRU THE DAY. BY LATE AFTN...H5 FLOW BECOMES LESS
CYCLONIC...SO EXPECT SHSN TO BEGINS TO TAPER OFF...BUT SHOULD STILL
SEE SOME FLURRIES.

OUTLOOK...MVFR CIGS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY. MVFR
CIGS/VSBYS POSSIBLE SUNDAY.
-- End Changed Discussion --

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
OH...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR OHZ026-
     034-035-042>046-051>056-060>065-070>074-077>082-088.
KY...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR
     KYZ089>100.
IN...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR INZ050-
     058-059-066-073>075-080.
-- End Changed Discussion --

&&

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