-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KILN 081756
AFDILN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1256 PM EST SUN DEC 8 2013

.SYNOPSIS...
LOW PRESSURE TRAVELING UP THE APPALACHIANS WILL BRING A MIXTURE OF
WINTRY PRECIPITATION TODAY INTO TONIGHT. HIGH PRESSURE WILL TRY TO
BUILD IN ON MONDAY...BUT ANOTHER WEAK SYSTEM WILL AFFECT THE
REGION ON TUESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
DECENT ISENTROPIC LIFT COMBINING WITH UPR LEVEL DIVERGENCE FROM
THE RR QUAD ENTRANCE REGION OF UPR LEVEL JET WILL PRODUCE
WIDESPREAD PCPN ACRS THE REGION THIS MORNING INTO THE FIRST PART OF
THIS AFTERNOON. WAA WILL GRADUALLY WARM ATMOSPHERIC COLUMN ALOFT FROM
SE TO NW THROUGH THE DAY. AS THIS OCCURS...SNOW WILL TRANSITION TO
A MIXTURE OF SLEET AND FREEZING RAIN. IT SHOULD WARM UP ENOUGH IN
THE FAR SE LATE THIS AFTERNOON FOR LIQUID PCPN. UPDATE THIS
MORNING WAS TO BUMP UP SNOWFALL AMOUNTS A BIT IN THE SE CWFA AS
SOME BURSTS OF MODERATE SNOW HAS ALREADY RESULTED IN ACCUMS AROUND
AN INCH. SO...2 TO 3 LOOKS GOOD HERE WITH 1 TO 2 FARTHER NORTH IN
DAYTON AND COLUMBUS METROS AND LESS THAN AN INCH NORTHWEST. LATEST
MODEL INDICATE THAT WE COULD END UP WITH LIGHTER PCPN THIS
EVENING/OVERNIGHT OVER MUCH OF THE REGION DUE TO DEEP MOISTURE
EXITING AND FORCING REMAINING FOCUSED NEAR THE SE WITH A LOW LEVEL
JET. WITH WARM TEMPS ALOFT AND SFC TEMPS NEAR OR SLIGHTLY BELOW
FREEZING WILL RESULT IN EITHER LIGHT FREEZING RAIN OR FREEZING
DRIZZLE. HEADLINES WILL HAVE TO BE ADJUSTED AT SOME POINT. TOSSED
AROUND ADDING OUR NW CWFA IN AN ADVISORY...BUT WILL WAIT FOR SOME
NEWER MODEL RUNS TO SEE IF PCPN WILL BE ENOUGH TO DO SO. TEMPS
STARTING OUT COLD WITH ANY LIGHT LIQUID PCPN WITH SFC TEMPS BELOW
FREEZING COULD CAUSE SOME ISSUES ON UNTREATED SIDEWALKS AND ROADS.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
THE DEEP MOISTURE BEGINS TO BE SHUNTED E AT THE BEGINNING OF THE
PERIOD...LEAVING THE W WITH VERY SHALLOW MOISTURE AND WEAKENING
LIFT. THIS IS A SETUP FOR MORE OF A FZDZ/FZRA SCENARIO AS
COMPARED TO SN/PL. THEREFORE BEGAN TO LOWER THE POPS IN THE W AND
INTRODUCED MORE OF THE FZDZ/FZRA. EXPECT MUCH OF THE AREA TO MAKE
THE CHANGE OVER AS TONIGHT PROGRESSES. THE EXCEPTION WILL BE THE
SE/E WHERE TEMPERATURES MIGHT STAY UP ALL NIGHT THEREFORE STAYING
ALL RAIN. THE ADVISORY IN THOSE LOCATIONS MIGHT BE TOO LONG...BUT
WILL NOT CHANGE THE TIMING RIGHT NOW. INSTEAD WILL LET LATER
SHIFTS CANCEL IT IF IT IS NOT NEEDED. LOWS TONIGHT SHOULD STAY UP
IN THE LOWER TO MID 30S IN THE SE...BUT WILL FALL INTO THE UPPER
20S BACK TO THE W AS THE COOLER AIR WORKS IN ON THE BACKSIDE OF
THE SYSTEM

AS THE SYSTEM SLIDES E EARLY MONDAY...THE REGION WILL BE STUCK
UNDER A SUBSIDENCE INVERSION...WHICH SHOULD KEEP LOW CLOUDS IN
THROUGHOUT THE DAY. RIGHT NOW ENDED THE DZ/FZDZ MONDAY MORNING...BUT
WITH THE LOW CLOUDS THE LIGHT PCPN COULD LINGER.

MONDAY NIGHT INTO TUESDAY SEES A SPLIT LEVEL FLOW DEVELOP WITH
A NRN STREAM VORT PIVOTING INTO THRU THE OHIO VALLEY LATE MONDAY
NIGHT INTO TUESDAY. MODELS PRODUCE AN RIBBON OF SNOW ALONG THE
LEADING EDGE OF THE ARCTIC AIR...WITH THE NAM THE QUICKEST AS IT
PUSHES THE SNOW IN MONDAY NIGHT. THE GFS AND ECMWF WAIT UNTIL
TUESDAY TO BRING THIS FEATURE IN. WILL LEAN TOWARD THE GFS/ECMWF
SOLUTION AND WILL KEEP A MENTION OF SNOW ACRS SE HALF OF FA
TUESDAY.

HIGHS MONDAY AND TUESDAY WILL REMAIN MUCH BELOW NORMAL. ON MONDAY
THEY WILL BE IN THE UPPER 20S IN THE NW TO THE MID 30S IN THE SE.
THEN ON TUESDAY WITH THE WEATHER SYSTEM WORKING THROUGH HIGHS WILL
ONLY REACH THE LOWE 20S IN THE N AND THE LOWER 30S IN THE S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE TO NOSE INTO THE OHIO VALLEY WEDNESDAY WITH WEAK
SYSTEM DROPPING THRU THE GREAT LAKES. THE FAVORABLE MSTR/LIFT TO
STAY TO OUR NORTH...SO HAVE MAINTAINED A DRY FCST WED. COLD
TEMPERATURES TO PERSIST WITH LOWS AROUND 10 DEGREES WEST TO 15
DEGREES SE AND HIGHS LOWER/MIDDLE 20S NW TO THE LOWER 30S SE.

SFC HIGH PRESSURE TO BUILD ACRS THE REGION THURSDAY/FRIDAY TIME
FRAME. COLD TEMPERATURES TO CONTINUE THURSDAY WITH MORNING LOWS
FROM SINGLE DIGITS OVER THE WEST WHERE SNOW COVER EXISTS TO NEAR 15
SE. HIGHS TO RANGE FROM THE LOWER 20S NW TO NEAR 30 SE.

SOME MODERATION TO TEMPERATURES EXPECTED FRIDAY ON BACK SIDE OF SFC
HIGH PRESSURE WITH HIGHS FROM LOWER 30S NW TO THE UPPER 30S SE.

MID LEVEL FLOW BACKS WITH SYSTEM EXPECTED TO DEVELOP ALONG THE
EASTERN SEABOARD LATE FRIDAY INTO SATURDAY. ILN FA IS ON THE FAR NW
FRINGE OF THIS SYSTEM AND HAVE LIMITED ANY MENTION OF PRECIP TO A
SLIGHT CHC OF A SNOW SHOWER IN THE FAR SE LATE FRIDAY NIGHT INTO
SATURDAY.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
STRONGEST WAA ASSOCIATED WITH UPPER LEVEL JET ENERGY WAS PIVOTING
NE OUT OF THE TAF REGION THIS AFTERNOON. A MIXTURE OF LIGHT
SNOW...SLEET AND FREEZING RAIN WILL TRANSITION OVER TO SOME PATCHY
LIGHT FREEZING RAIN OR LIGHT FREEZING DRIZZLE AS DEEP MOISTURE
GETS REPLACED WITH LOW LEVEL MOISTURE...WICH WILL LACK ICE
NUCLEATION FOR SNOW DEVELOPMENT.

FOR TONIGHT...A FRONTAL BOUNDARY WILL APPROACH THE REGION FROM THE
WEST AND WILL PUSH ACROSS THE TAF SITES LATE TONIGHT INTO MONDAY.
CONTINUED MOIST LOW LEVEL WAA AHEAD OF THE FRONT WILL RESULT IN
LOW CEILINGS AND VISIBILITIES...ALONG WITH SOME LIGHT FREEZING
RAIN/LIGHT FREEZING DRIZZLE OR IN THE LIQUID FORM AT SOME POINT
(KCMH/KLCK) BEFORE THE FRONT PUSHES BY. KEPT VISIBILITIES AS LOW
AS 1SM BUT WOULD NOT BE SURPRISED IF SOME POCKETS OF 1/2SM OR LESS
DEVELOP. ONCE THE FRONT MOVES THROUGH...DRIER AIR IN THE LOWER
LEVELS WILL RESULT IN A SLOW IMPROVEMENT IN VISIBILITIES AND
CEILINGS ON MONDAY...WITH MVFR CEILINGS AT LEAST CONTINUING INTO
THE AFTERNOON HOURS.

OUTLOOK...MVFR CEILINGS TO LINGER INTO MONDAY EVENING.
-- End Changed Discussion --

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR OHZ045-046-
     051>056-060>065-070>074-077>082-088.
KY...WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR KYZ089>100.
IN...WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR INZ050-058-
     059-066-073>075-080.

&&

$$
SYNOPSIS...CONIGLIO/SITES
NEAR TERM...HICKMAN/SITES
SHORT TERM...SITES
LONG TERM...AR
AVIATION...HICKMAN