FXUS61 KILN 231738
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1238 PM EST WED DEC 23 2009
.SYNOPSIS...
UPPER LEVEL RIDGING WILL BUILD INTO THE OHIO VALLEY TODAY AND MOVE
EAST OF THE AREA ON THURSDAY. A STRONG UPPER LOW WILL DIG INTO THE
CENTRAL U.S. THURSDAY AND FRIDAY...BRINGING WIDESPREAD RAIN INTO
THE OHIO VALLEY BY THURSDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CHAOTIC PATTERN WILL CONTINUE IN THE NEAR TERM.
HAD CANCELLED WINTER WX ADVISORY THAT WAS ORIGINALLY IN EFFECT FOR
THE WHITEWATER VALLEY...THE MIAMI VALLEY AND CENTRAL OHIO UNTIL NOON.
HOWEVER...BASED ON LATEST RADAR MOSAIC...IT APPEARS THAT PCPN IS
MOVING BACK INTO THE FAR WRN CWFA. THIS AREA MAY GET AFFECTED BY A
MIXED BAG OF PCPN INTO THE AFTN HOURS. MAY HANDLE THIS WITH AN SPS
OR MAY HAVE TO ISSUE A BRAND NEW WINTER WEATHER ADVISORY IF
ROADS/SIDEWALKS ETC. BECOME A PROBLEM. OTHERWISE...MAIN BULK OF
PCPN TODAY SHOULD REMAIN ACRS INDIANA. THE REMAINDER OF THE
FORECAST AREA...MAINLY THE ERN ZONES...SHOULD BE MOSTLY CLOUDY
AND DRY.
TEMPERATURES WILL STRUGGLE TO WARM INTO THE LOWER 30S NORTH AND
EAST WITH SOME LOWER 40S EXPECTED TO BULGE NE INTO THE FAR SWRN
CWFA THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
UPPER RIDGE WILL BECOME CENTERED OVER THE OHIO VALLEY TONIGHT...AS
UPPER LEVEL PATTERN AMPLIFIES AND DEEP UPPER LOW DIGS INTO THE
CENTRAL PLAINS. THIS WILL RESULT IN A RAPIDLY DEEPENING SURFACE
LOW OVER THE OZARKS ON THURSDAY...WHICH WILL OCCLUDE AS IT DRIFTS
NORTH INTO NEBRASKA AND IOWA THROUGH FRIDAY. THIS WILL KEEP MOST
PRECIP FOCUSED ACROSS THE MISSISSIPPI VALLEY WEDS NIGHT...WITH
MOST MODELS KEEPING THE CWA DRY THROUGH EARLY THURSDAY.
HOWEVER...THERE WILL BE SOME WEAK ISENTROPIC LIFT ACROSS AREAS
NEAR AND WEST OF I-75 TONIGHT AND EARLY THURSDAY. GIVEN A
RELATIVELY SATURATED COLUMN...THIS MAY BE ENOUGH TO PRODUCE SOME
LIGHT PRECIP ACROSS THE WESTERN CWA WEDS NIGHT AND THURS MORNING.
THERMAL PROFILES WOULD SUPPORT A MIXTURE OF SNOW AND SLEET ACROSS
THE NORTHWEST HALF OF THE CWA...WITH SLEET AND FREEZING RAIN
ACROSS THE SOUTHWEST. HOWEVER GIVEN THE LIMITED LIFT...THE
CHANCES FOR MEASURABLE WINTRY PRECIP ARE LOW...AND ONLY INCLUDED
A SLIGHT CHANCE ACROSS AREAS WEST OF I-75 WEDS NIGHT.
WARM AIR ADVECTION INCREASES FROM THE SOUTHWEST BY THURSDAY
AFTERNOON...WITH PRECIP BECOMING LIKELY ACROSS THE SOUTHWESTERN
CWA BY LATE THURSDAY. THERMAL PROFILES BY THIS TIME WILL SUPPORT
ALL RAIN. RAIN WILL OVERSPREAD THE REGION FROM SOUTHWEST TO
NORTHEAST THURSDAY NIGHT. 70-KT LOW LEVEL JET WILL ENHANCE LOW
LEVEL UPGLIDE AND CONVERGENCE...WHICH COMBINED WITH PRECIPITABLE
WATER VALUES NEAR ONE INCH...WILL LIKELY RESULT IN HEALTHY RAIN
AMOUNTS WHICH MAY APPROACH ONE INCH IN SPOTS. TIGHT PRESSURE
GRADIENT WILL RESULT IN A STIFF EAST-SOUTHEAST WIND THURSDAY
NIGHT. HOWEVER VERY STRONG LOW LEVEL INVERSION AND LACK OF ANY
INSTABILITY WILL PREVENT STRONG WINDS ALOFT FROM MIXING
DOWN...THOUGH GUSTS TO 35 MPH ARE POSSIBLE.
PRECIP WILL SHIFT TO THE NORTHEAST ON CHRISTMAS DAY AS UPPER LOW
MOVES IN FROM THE WEST. WILL LIKELY SEE SCATTERED SHOWERS
REDEVELOP DURING THE AFTERNOON DUE TO THE PROXIMITY OF THE UPPER
LOW AND AREAS OF PVA. BULK OF COLD AIR ADVECTION DOES NOT MOVE IN
UNTIL LATE FRIDAY...WHEN BEST MOISTURE AND LIFT WILL BE PUSHING
EAST OF THE CWA. WHILE THERE MAY BE A FEW LIGHT SHOWERS CHANGING
TO LIGHT SNOW SHOWERS OR FLURRIES FRIDAY NIGHT...THE CHANCE FOR
ANY MEASURABLE SNOW FRIDAY NIGHT LOOKS SLIM.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
CLOSED LOW WILL REMAIN OVER THE GREAT LAKES SATURDAY AND
SUNDAY...WITH LIMITED MOISTURE AND ENERGY RESULTING IN SCATTERED
SNOW SHOWERS. ADDITIONAL SNOW SHOWERS MAY BE IN STORE FOR MONDAY
WHEN THE LOW IS PROGGED TO FINALLY EJECT EASTWARD. BOTH ECMWF AND
GFS BRING HIGH PRESSURE AND DRY WEATHER NEXT TUESDAY.
TEMPERATURES WILL BE RATHER MILD FRIDAY WITH HIGHS IN THE LOW TO MID
40S. IN A PATTERN CONSISTING MAINLY OF COLD ADVECTION...HIGHS IN THE
20S AND 30S CAN BE EXPECTED SATURDAY THROUGH TUESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A MID LVL RIDGE IS FORECAST TO MOVE EAST ACROSS THE FORECAST AREA
OVERNIGHT. ANY PCPN CHC/S WILL BE SMALL AND RELEGATED NEAR THE
OHIO/INDIANA BORDER. THUS...AM FORECASTING VFR CONDITIONS...EXCEPT
SOME LOCAL IFR CIGS NEAR KILN EARLY IN THE TAF FORECAST. ON
THURSDAY...STORM SYSTEM WILL CONTINUE TO TAKE SHAPE OVER SRN/CNTRL
PLAINS. MID LVL RIDGE WILL MOVE OFF TO THE EAST. THIS WILL ALLOW
FOR SOME SHOWERS TO SKIM THE WRN TAF SITES DURING THE LATE
MORNING/AFTN HOURS. SHOWERS WILL BE LIGHT AND THUS...VFR
CONDITIONS SHOULD STILL PREVAIL. WIDESPREAD RAIN IS EXPECTED
THURSDAY NIGHT INTO FRIDAY AS A COLD FRONT APPROACHES AND
EVENTUALLY PASSES ACROSS THE AREA.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES EXPECTED THURSDAY NIGHT
INTO FRIDAY WITH PERIODS OF IFR CEILINGS AND VISIBILITIES
POSSIBLE. MVFR CEILINGS WILL LIKELY PERSIST THROUGH SUNDAY WITH
MVFR VISIBILITIES POSSIBLE.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HAWBLITZEL
NEAR TERM...HICKMAN
SHORT TERM...HAWBLITZEL
LONG TERM...CONIGLIO
AVIATION...HICKMAN
