FXUS61 KRLX 221847
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
147 PM EST TUE DEC 22 2009
.SYNOPSIS...
HIGH PRESSURE GIVING WAY TO A LOW PRESSURE SYSTEM FOR CHRISTMAS.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
WEAK ISENTROPIC LIFT THIS AFTERNOON GIVING SOME FLURRIES. LIFT DIES
THIS EVENING. UNTIL LOW GETS CLOSER LATER IN THE WEEK THE LOW LEVEL
MOISTURE WILL STILL BE AROUND SO SOME CLOUDS WILL CONTINUE. PLAYED
MIN TEMPS TONIGHT A BIT HIGHER THEN MOS WITH LOW LEVEL MOISTURE
AROUND. ALSO WENT A BIT BELOW MAX WED WITH SNOW STILL IN PLACE.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS ARE GENERALLY CONSISTANT WITH TRACKING SFC LOW FURTHER WEST
AND BRINGING OCCULUDED FRONT THROUGH THE REGION DURING THE DAY ON
FRIDAY. TIMING DIFFERENCES ARE STILL PREVIELENT WITH NAM BEING THE
SLOWEST AND OVERALL ALL MODELS A TAD SLOWER. SO HELD OFF ON THE START OF
PRECIP ON THURSDAY TIL LATE AFERNOON AND BRING POPS IN FROM SW TO
NE DURING THURSDAY NIGHT AND CAT POPS ON FRIDAY. 85H TEMPERATURES
WARM AS WELL THROUGH THE PERIOD. INITIALLY TEMPERATURES AT THE
SURFACE WILL BE COLD ENOUGH IN THE EASTERN MOUNTAIN VALLEYS TO
HAVE PRECIP START OUT AS FREEZING RAIN THURSDAY NIGHT AND CONTINUE
INTO CHRISTMAS MORNING BEFORE CHANGING TO ALL RAIN. FRONTAL
PASSAGE FAIRLY QUICK AND ONLY EXPECTING 1/4 TO 1/2 INCHES OF RAIN
AT THE MOST ON THE SNOW PACK. WE WILL SEE SOME RISES IN THE
RIVERS WITH SOME SNOWMELT...BUT NOT EXPECTING ANY MAJOR PROBLEMS
RIVER WISE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
FRIDAY NIGHT IS BEGINNING TO LOOK LIKE A MESSY NIGHT AS LATEST
MODELS DO NOT BRING IN THE COLD AIR ALOFT UNTIL AFTER 00Z IN THE
WEST AND 06Z IN THE EAST. WITH THIS IN MIND...APPEARS PRECIPITATION
IN THE MOUNTAINS COULD BE A WINTRY MIX OF RAIN...TO FREEZING
RAIN/SLEET TO SNOW WITH THE PRECIPITATION. ACROSS THE LOWLANDS...
THE PRECIPITATION SHOULD GENERALLY CHANGING TO A MIX OF RAIN/SNOW
AND THEN ALL SNOW. HAVE GONE WITH A NON-DIURNAL TEMP CURVE AS TEMPS
SHOULD NOT FALL ACROSS THE HIGHER ELEVATIONS UNTIL LATER.
THE REGION SHOULD THEN REMAIN UNDER THE INFLUENCE OF AN UPPER LEVEL
LOW...WITH CONTINUED CHANCES OF SNOW SHOWERS THRU THE WEEKEND.
SURFACE HIGH PRESSURE THEN BUILD IN LATE IN THE PERIOD...SHUTTING
OFF ANY PRECIP CHANCES.
GENERALLY USED HPC TEMP GUIDANCE...WITH SOME TWEAKS TO REFLECT
LATEST ENSEMBLE GUIDANCE.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
THERE WILL BE ENOUGH LOW LEVEL MOISTURE STILL AROUND TO KEEP CLOUDS
THROUGH THE PERIOD. CIGS WILL BE VFR SOUTH TO MVFR ACROSS CENTRAL
WEST VIRGINIA AND NORTH. VSBYS WILL LOWER TO MVFR LEVELS WITH A BIT
OF FOG AROUND TONIGHT. SOME IFR VSBYS WILL BE ENCOUNTERED IN RIVER
VALLEYS 06Z TO 14Z.
AFTER 18Z WEDNESDAY...
SYSTEM IMPACTS AREA THURSDAY NIGHT INTO FRIDAY...WITH RAIN AND
POSSIBLE IFR. FREEZING RAIN ALSO A THREAT IN THE WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...AAR/SL/JS
NEAR TERM...AAR
SHORT TERM...JS
LONG TERM...SL
AVIATION...AAR
