FXUS61 KILN 231142
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
642 AM 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/...
PRECIP IS OVERSPREADING MUCH OF EASTERN INDIANA AND WESTERN OHIO
THIS MORNING IN RESPONSE TO WEAK ISENTROPIC LIFT. SURFACE TEMPS
ARE BELOW FREEZING NEAR AND NORTH OF THE I-70 CORRIDOR. SEEING
REPORTS OF SNOW AND ICE ACROSS THIS AREA...WITH SOME REPORTS OF
ICY ROADS ACROSS EASTERN INDIANA...WHERE A WINTER WEATHER ADVISORY
HAS BEEN ISSUED. MODELS SHOWING THE PRECIP HAVING A DIFFICULT
TIME MAKING IT MUCH FURTHER EAST THIS MORNING. WHILE PRECIP SHOULD
DECREASE IN INTENSITY AS IT PUSHES INTO CENTRAL OHIO...DO NOT
EXPECT IT TO TOTALLY DISSIPATE GIVEN THE MOIST LOW LEVELS ACROSS
THIS AREA. THEREFORE WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR
AREAS ROUGHLY ALONG THE I-70 CORRIDOR FROM EASTERN
INDIANA...THROUGH THE MIAMI VALLEY...AND INTO THE COLUMBUS METRO
THROUGH NOON. DID NOT INCLUDE AREAS NORTH OF THE DAYTON OR
COLUMBUS METROS SINCE PRECIP APPEARS TO BE PRIMARILY SNOW FURTHER
NORTH...AND PRECIP RATES ARE WEAKER ACROSS THAT AREA AS WELL. TO
THE SOUTH OF I-70...SFC TEMPS ABOVE FREEZING SHOULD KEEP PRECIP
PRIMARILY RAIN...BUT THERE MAY BE SOME SLEET OR SNOW MIXED IT AT
TIMES THIS MORNING.
AFTER THIS INITIAL BATCH OF PRECIP MOVES THROUGH THIS
MORNING...BULK OF PRECIP WILL BE CONCENTRATED TO THE WEST OF THE
CWA BY AFTERNOON WHERE THE BETTER LIFT WILL BE FOCUSED. ANY
LINGERING PRECIP OVER THIS AREA WILL BECOME ALL RAIN THIS
AFTERNOON AS SFC TEMPS WARM ABOVE FREEZING.
&&
.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 TUESDAY/...
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 /12Z WEDNESDAY THROUGH SUNDAY/...
ISENTROPIC LIFT HELPING TO PRODUCE SOME FAIRLY WIDESPREAD PCPN
ACROSS OUR AREA THIS MORNING. PCPN ALONG AND NORTH OF INTERSTATE
70 HAS BEEN MAINLY SNOW WITH THEN A NARROW BAND OF SNOW...SLEET
AND FREEZING RAIN ACROSS CENTRAL PORTIONS OF OUR FA AND THEN JUST
RAIN ACROSS OUR SOUTH. THE ISENTROPIC LIFT IS FORECAST TO WEAKEN
ACROSS OUR AREA THROUGH 18Z SO EXPECT TO SEE A GRADUAL DECREASE IN
INTENSITY/COVERAGE THROUGH LATE MORNING. INCREASING WAA OFF THE
SURFACE WILL LIKELY ALLOW THE EDGE OF MIXED PCPN TO INCH ITS WAY
NORTHWARD THROUGH THE REST OF THE MORNING. NOT SURE IF IT WILL
MAKE IT ALL THE WAY UP INTO THE COLUMBUS AREA THOUGH SO WILL KEEP
PCPN ALL SNOW THERE FOR NOW. FOR KDAY/KILN WILL KEEP A MIXED BAG
OF PCPN GOING THIS MORNING WITH ALL RAIN AT KCVG/KLUK. GENERALLY
EXPECT LOW VFR TO MVFR CIGS WITH THE PCPN THROUGH THIS MORNING.
LOW LEVEL SOUTHERLY FLOW WILL INCREASE THIS AFTERNOON AS MID/UPPER
LEVEL RIDGING DEVELOPS OVERHEAD. MODELS ARE INDICATING SOME DECENT
LOW LEVEL DRYING WITH THIS SO WILL JUST HANG ON TO SOME AC ON
INTO TONIGHT. SOME WEAK ISENTROPIC LIFT DOES TRY TO WORK BACK INTO
THE WEST LATE TONIGHT. SUPPOSE THIS MAY BE ENOUGH FOR A AN
ISOLATED SHOWER BUT CHANCE APPEARS LOW ENOUGH TO LEAVE OUT OF THE
TAFS.
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...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR OHZ042-
051>056-060>065-072.
KY...NONE.
IN...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR INZ050-058-
059.
&&
$$
SYNOPSIS...HAWBLITZEL
NEAR TERM...HAWBLITZEL
SHORT TERM...HAWBLITZEL
LONG TERM...CONIGLIO
AVIATION...JGL
