FXUS61 KRLX 260749
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
248 AM EST THU NOV 26 2009
.SYNOPSIS...
A GENERALLY DRY COLD FRONT MOVES THROUGH TODAY. COLD NORTHWEST FLOW
LEADS TO ACCUMULATING SNOW IN THE MOUNTAINS INTO FRIDAY NIGHT. HIGH
PRESSURE RETURNS FOR THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
A REINFORCING COLD FRONT PUSHES THROUGH THE REGION TODAY. MOISTURE
IS LIMITED HOWEVER...SO WILL REMOVE POPS FROM THE SOUTH AND ONLY
HAVE VERY SMALL POPS IN THE NORTH. COLDER AIR MOVES INTO THE REGION
TODAY...SETTING UP A NORTHWEST FLOW EVENT LATE TONIGHT. NOT THE BEST
SETUP HOWEVER. MOISTURE DEPTH INCREASES BEHIND THE STRONG VORTICITY
LOBE...SO THE LOBE DOES NOT HELP MUCH IN AIDING THE PRECIPITATION.
DENDRITIC GROWTH ZONE IS WELL ABOVE THE MOUNTAIN FORCING LAYER AND
NEAR THE TOP OF THE MOISTURE LAYER. OVERALL...FEEL ONLY THE HIGHEST
ELEVATIONS WILL SEE MUCH ACCUMULATION WITH ONLY A SUGAR COATING IN
THE LOWER ELEVATIONS OF THE MOUNTAINS. BOUNDARY LAYER THURSDAY NIGHT
MAY BE TOO WARM FOR SNOW IN THE LOWLANDS.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
MAIN UPPER LEVEL SYSTEM AND ASSOCIATED FORCING MECHANISMS SHOULD BE
EAST OF REGION EARLY FRIDAY. MODELS DO INDICATE A WEAK SHORTWAVE
WILL SWING EAST ON FRIDAY. IN ADDITION...COLD WNW UPSLOPE WINDS
WILL BE IN PLACE SUGGESTING THE POSSIBILITY OF HEAVY SNOW ACROSS THE
HIGHER ELEVATIONS.
H8 TEMPS OF MINUS 6 TO MINUS 8 C ARE EXPECTED ALONG WITH WNW WINDS
OF 30-35 KT. HOWEVER...BUFKIT SOUNDINGS INDICATE MOISTURE WILL NOT
BE THAT DEEP...WITH MINUS 10 C ISOTHERM RIGHT AT THE TOP OF THE
MOISTURE COLUMN.
THESE CONDITIONS ARE EXPECTED TO CONTINUE FRIDAY INTO EARLY FRIDAY
NIGHT...AS HIGH PRESSURE BUILDS IN. AS A RESULT...THE MOISTURE IS
EXPECTED TO DECREASE. CURRENT THINKING IS THAT PRECIPITATION WILL
END FROM THE WEST FRIDAY EVENING THRU SATURDAY NIGHT...WITH ENTIRE
AREA DRY BY LATE FRIDAY NIGHT.
CURRENT THINKING IS THAT AREAS ABOVE 3500 FT COULD SEE AROUND 8
INCHES OF SNOW WITH LESSOR AMOUNTS ACROSS THE REMAINDER OF THE
MOUNTAINS. MANY LOWLAND LOCATIONS WILL LIKELY SEE THEIR FIRST
SNOWFLAKES OF THE SEASON. HOWEVER...NO ACCUMULATIONS ARE
ANTICIPATED.
STILL FEEL THERE IS NO NEED FOR ANY WINTER WEATHER HEADLINES AS
COUNTY AVERAGE CRITERIA SHOULD NOT BE MET DURING THIS EVENT.
WEAK HIGH PRESSURE AND A WARMING TREND ARE EXPECTED SATURDAY THROUGH
SUNDAY. AN APPROACHING COLD FRONT SHOULD RESULT IN INCREASING CLOUDS
SUNDAY NIGHT...ALONG WITH THE POSSIBILITY OF A FEW RAIN SHOWERS
ACROSS SOUTHEAST OHIO AND NORTHEAST KENTUCKY AS WELL AS WEST
VIRGINIA COUNTIES NEAR THE OHIO RIVER.
FOR THE MOST PART...LATEST TEMP GUIDANCE IS CLOSE TO PREVIOUS
FORECAST NUMBERS AND WILL BE FOLLOWED. THE EXCEPTIONS ARE SUNDAY
AND SUNDAY NIGHT...WHERE NEW GUIDANCE SUGGESTS WARMER TEMPERATURES
SHOULD PREVAIL. HAVE TWEAKED NUMBERS UP A LITTLE TO REFLECT THIS
THINKING.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WITH DRY WEATHER AND A WARMING TREND FOR THE WEEKEND
IS EXPECTED.
THERE IS MUCH DIVERSITY IN THE MODELS IN HANDLING THE LOW PRESSURE
SYSTEM AFFECTING OUR AREA EARLY NEXT WEEK. WHILE ALL THE MODELS
SPLIT THE ENERGY TO SOME DEGREE IN THE HIGHLY AMPLIFIED UPPER TROUGH
THAT APPROACHES US FROM THE WEST...THE PREFERRED SOLUTION PER
HPC...WHICH IS SUPPORTED BY MAJORITY OF ENSEMBLES...WOULD BE THE
OPERATIONAL ECMWF. THIS MODEL HAS THE NORTHERN PORTION OF THE UPPER
TROUGH AND ASSOCIATED COLD FRONT MOVING RIGHT ALONG...WHILE SOUTHERN
ENERGY CLOSES OFF OVER THE SOUTHERN MISSISSIPPI VALLEY BY TUESDAY.
THIS SCENARIO THEN HAS THE COLD FRONT CROSS OUR AREA MONDAY AND
MONDAY NIGHT...THEN STALLING OVER THE SOUTHEASTERN STATES TUESDAY. A
SURFACE WAVE ALONG THE FRONT WITH THE SOUTHERN ENERGY THEN LIFTS
NORTH AND EAST TOWARD THE MID ATLANTIC STATES FOR MID WEEK.
THIS ACCEPTED SOLUTION WOULD HAVE THE BULK OF THE RAIN WITH THIS
FRONT COMING ACROSS MONDAY AND MONDAY NIGHT...FOLLOWED BY SCATTERED
POST FRONTAL RAIN SHOWERS MAINLY SOUTHEAST TUESDAY. GOOD INFLUX OF
MOISTURE WILL BRING A GOOD SLUG OF RAIN...BUT INSTABILITY FOR
THUNDER REMAINS LOW. RAIN THEN WORKS BACK NORTHWARD WITH THE FRONTAL
WAVE ACROSS AT LEAST THE EASTERN HALF OF WEST VIRGINIA WEDNESDAY.
TEMPERATURES WILL BE QUITE MILD AHEAD OF THE FRONT MONDAY. COLD AIR
INTRUSION BEHIND THE FRONT WILL TEMPERED BY THE SOUTHERN SYSTEM
LIFTING UP FOR MID MEEK. THUS...TEMPERATURES WILL FALL BACK TO NEAR
NORMAL BEHIND THE FRONT...WITH SOME REALLY COLD AIR WAITING FOR THE
MID WEEK SYSTEM TO MOVE OUT.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR STRATUS DECK FORMING AGAIN OVER THE REGION EARLY THIS MORNING.
THIS SHOULD HELP TO RAISE VISIBILITIES IN THE MOUNTAIN VALLEYS WHERE
FOG WAS STARTING TO FORM. A REINFORCING COLD FRONT WILL PUSH THROUGH
THIS MORNING...BUT MOISTURE IS LIMITED WITH THE FRONT. CEILINGS WILL
GENERALLY REMAIN VFR...WITH ONLY A SLIGHT CHANCE OF A MVFR SHOWER.
AS COLDER AIR FILTERS INTO THE REGION TONIGHT...CEILINGS WILL BE
DROPPING.
AFTER 06Z FRIDAY...
IFR CONDITIONS EXPECTED LATE THURSDAY NIGHT AND FRIDAY IN
RAIN/SNOW OR SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/JMV/RPY
NEAR TERM...RPY
SHORT TERM...JSH
LONG TERM...JMV
AVIATION...RPY
