FXUS61 KRLX 271457
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
957 AM EST FRI NOV 27 2009
.SYNOPSIS...
COLD NORTHWEST FLOW BRINGS RAIN AND SNOW SHOWERS...WITH ACCUMULATING
SNOW IN THE MOUNTAINS THROUGH TONIGHT. HIGH PRESSURE RETURNS FOR
THIS WEEKEND. COLD FRONT WITH RAIN MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRETTY MUCH AT MAX COVERAGE OF -SHSN ACROSS THE CWA RIGHT NOW.
WINDS ARE TURNING MORE WNW WITH TIME...AND EXPECT TRANSITION TO A
PURE UPSLOPE SNOW EVENT OVER THE NEXT SEVERAL HOURS. ACCUMULATIONS
SO FAR HAVE GENERALLY BEEN AROUND AN INCH IN THE HIGHER
ELEVATIONS...WITH LITTLE TO NONE IN THE LOWLANDS. WARM GROUND AND
MOSTLY ABOVE FREEZING TEMPERATURES ARE THE REASONS FOR LITTLE
ACCUMULATION. BUMPED UP POPS IN THE LOWLANDS FOR A FEW HOURS BASED
ON CURRENT COVERAGE. MOISTURE STARTS TO WANE AFTER MIDDAY AS VORT
LOBE ROTATES OUT...AND EXPECT LITTLE ACTIVITY OUTSIDE OF THE MOUNTAINS
BY SUNSET. STILL COULD SEE 1-3 INCHES ON THE HIGHER PEAKS
TODAY...AROUND AN INCH IN LOWER AREAS IN THE MOUNTAINOUS
COUNTIES...AND NO ACCUMULATION ELSEWHERE. TEMPERATURES IN DECENT
SHAPE AND ONLY TWEAKED HERE AND THERE.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
AS THE NORTHWEST FLOW WINDS DOWN...A DRY ATMOSPHERE TAKES OVER WITH
BROAD SCALE UPPER LEVEL HIGH PRESSURE. SURFACE HIGH PRESSURE WILL
CONTROL MORE OF THE SOUTHEASTERN CONUS AND ALLOW THE CWA TO BE
AFFECTED BY THE NEXT INCOMING FRONTAL SYSTEM. UNTIL THIS
POINT...HIGH LEVEL CLOUDS BEGIN TO INCREASE AS THE UPPER LEVEL FLOW
BEGINS TO TURN MORE SOUTHWESTERLY WITH THE RIDGE NOW DOWNSTREAM.
COLD FRONT WILL BE A LATE SUNDAY NIGHT AND MONDAY FEATURE...AND
LOOKS TO BE BOTH WELL ORGANIZED AND STRONG ENOUGH TO PASS THROUGH
THE MOUNTAINS TO THE EAST. COLD AIR ADVECTION BRINGS MILD WEATHER
BACK DOWN BELOW NORMAL BEHIND THE FRONT INTO WEDNESDAY AS HIGH
PRESSURE INFLUENCES MAKE A COMEBACK.
SATURDAY NIGHT LOOKS LIKE A SCENARIO FOR EFFICIENT RADIATIONAL
COOLING...ESPECIALLY IN THE SHELTERED VALLEYS WITHIN THE HIGHER
ELEVATIONS. THIS WILL BE OFFSET A BIT LATER WITH CIRRUS ADVECTION.
TIMING WILL BE CRUCIAL HERE IN DETERMINING JUST HOW FAR DOWN TO TAKE
LOCATIONS LIKE ELKINS.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
ALL THE MODELS HAVE NORTHERN STREAM FLOW DOMINATING EARLY NEXT WEEK.
PER HPC...WE ARE FOLLOWING THE OPERATIONAL ECMWF FOR DETAILS AS
OTHER MODELS...ALONG WITH MUCH OF THEIR ENSEMBLES...HAVE TRENDED
TOWARD THIS MOST CONSISTENT ECMWF...WHICH SHOWED THIS SCENARIO
FIRST.
THIS ACCEPTED SCENARIO HAS A COLD FRONT IN THIS NORTHERN STREAM
MOVING STEADILY ACROSS THE OHIO VALLEY ON MONDAY...EXITING THE
MOUNTAINS BY MONDAY NIGHT. MODELS SHOWING A GOOD SLUG OF MOISTURE
AND MILD AIR AHEAD OF THIS FRONT...BUT INSTABILITY REMAINS ALMOST
NIL. THUS...EXPECT A GOOD SLUG OF RAIN MONDAY...WHICH BEING ON THE
LAST DAY OF NOVEMBER WILL LIKELY ERASE OUR POTENTIAL DRIEST NOVEMBER
ON RECORD. WITH MUCH OF THE RAIN BEING POST FRONTAL...HAVE CONTINUED
POPS MONDAY NIGHT...AND INTO TUESDAY MORNING IN THE MOUNTAINS. LOOKS
LIKE ENOUGH COLD AIR ALOFT COMES IN FOR SOME CHANGEOVER TO SNOW
SHOWERS IN THE HIGHER ELEVATIONS OF THE NORTHERN WEST VIRGINA
MOUNTAINS LATER MONDAY NIGHT AND EARLY TUESDAY...WITH LITTLE
ACCUMULATION. THEN...LOOK FOR A BREAK WITH HIGH PRESSURE BUILDING
ACROSS ON TUESDAY AND TUESDAY NIGHT.
MEANWHILE...WHILE THE NORTHERN STREAM HAS MOVED RIGHT ALONG...
SOUTHERN ENERGY IN THE FORM OF A CLOSED UPPER LOW HANGS BACK OVER
THE SOUTHERN PLAINS EARLY NEXT WEEK. THIS SOUTHERN SYSTEM IS THEN
PROGGED TO LIFT NORTHEASTWARD TOWARD THE OHIO VALLEY WEDNESDAY AND
THURSDAY...AS A NEW POWERFUL NORTHERN STREAM SYSTEM DIVES INTO THE
PLAINS STATES. THIS WILL BRING ANOTHER SURGE OF MILD AIR AND A GOOD
SLUG OF MOISTURE FOR RAIN DURING WEDNESDAY INTO THURSDAY TO OUR AREA.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
RADAR IMAGES CONTINUE TO SHOW LIGHT RAIN/SNOW MIX ACROSS THE
LOWLANDS...AND SNOW SHOWERS ACROSS THE EASTERN MOUNTAINS WHERE
TEMPERATURES ARE BELOW 32F. IFR VISIBILITIES WILL BE AROUND 2 MILES
AND CEILINGS AROUND 900 FEET UNDER LIGHT SNOW SHOWERS. OUTSIDE
SHOWERS...CEILINGS CAN BE AROUND 1200 FEET THIS MORNING. EXPECT
CONDITIONS TO IMPROVE TO VFR AT MOST SITES AS CLEARING SPREADS FROM
SOUTH TO NORTH THIS AFTERNOON WHILE THE UPPER LEVEL SYSTEM EXITS
NORTHEAST.
GUSTY WINDS WILL CONTINUE ACROSS MOST SITES EXCEPT FOR THOSE
PROTECTED BY MOUNTAINS LIKE EKN. BUT EVEN EKN WILL BE GUSTY UNDER
SNOW SHOWERS DURING THE MORNING HOURS. FLOW SHIFTS WNW AND REMAIN
SOMEWHAT GUSTY MOST OF THE DAY.
AFTER 12Z SATURDAY...
NO SIGNIFICANT IFR CONDITIONS ARE EXPECTED AT THIS TIME.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...26/ARJ
NEAR TERM...CL
SHORT TERM...26
LONG TERM...JMV
AVIATION...ARJ