FXUS61 KRLX 301933
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
233 PM EST MON NOV 30 2009
.SYNOPSIS...
PRECIPITATION AND FRONT MOVE EAST. HIGH PRESSURE RETURNS LATER
TONIGHT AND TUESDAY. LOW PRESSURE PASSES THURSDAY MORNING. COLDER
THURSDAY NIGHT AND FRIDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
SURFACE PRECIPITATION AND FRONT MOVING EAST WITH CONSISTENCY IN THE
MODELS. UPPER TROUGH WILL MOVE ACROSS THE FORECAST AREA BY AROUND
06Z. POSITION OF HIGH BUILDING INTO THE REGION AND MORE WESTERLY
ORIENTATION OF UPPER FLOW WILL MEAN CLEARING RATHER THEN THE NORMAL
WINTER NORTHWEST FLOW CLOUDINESS. AS COLD AIR COMES IN THE RAIN WILL
BRIEFLY SWITCH TO SNOW SHOWERS IN THE MOUNTAINS BEFORE SWITCHING
OVER BUT ANY ACCUMULATIONS WILL BE LIGHT IN THE HIGHER ELEVATIONS.
HIGH WILL MEAN CLEAR SKIES FOR TUESDAY.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
SFC HIGH PRESSURE PROVIDES DRY WEATHER THROUGH TUESDAY NIGHT. PLENTY
OF SUNSHINE WILL BRING MILD TEMPERATURES DURING THE DAY...BUT NEAR
FREEZING TEMPERATURES TUE NIGHT INTO WED MORNING DUE TO RADIATIONAL
COOLING. WENT WITH THE BIAS CORRECTED SREF FOR TEMPS THRU TUE NIGHT.
A LOW PRESSURE SYSTEM DEVELOPS ALONG THE GULF OF MEXICO STATES
WED...TRACKING NORTH NORTHEAST INTO THE TN VALLEY. THE GFS AND SREF
HAVE SIMILAR TIMING OF THE ONSET OF PCPN REACHING SOUTHERN WV BY WED
12Z...SPREADING NORTHEAST WITH TWO AREAS OF MAX PCPN...ONE ALONG THE
EASTERN MOUNTAINS...THE OTHER ALONG SOUTHEAST OH. THE NAM AND ECMWF
LAG ABOUT 6-12 HOURS...WITH BULK OF PCPN TARGETING SOUTHEAST OH AND
LESS PCPN ACROSS THE EASTERN MOUNTAINS. ADJUSTED CATEGORICAL POPS
WED NIGHT.
MODELS SHOW MODERATE TO STRONG SOUTHERLY FLOW AT H8. THIS IMPLIES
STRONG WARM ADVECTION PERHAPS NOT HANDLED WELL BY MODELS.
THEREFORE...DECIDED TO GO FEW DEGREES WARMER THAN GUIDANCE FOR HIGH
TEMPERATURES ON WED. IN ADDITION...INCREASE WIND GUSTS ON WED
AFTERNOON AND NIGHT PER MOST MODELS SHOWING H8 WIND FROM 50 TO 70
KNOTS. ALTHOUGH FLOW LOOKS UPGLIDING IN ISENTROPIC SFC...KEPT
HIGHEST WIND GUSTS ALONG THE WESTERN SLOPES AND HIGHER RIDGES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
MODELS DIFFER IN TIMING OF SYSTEMS THROUGH THE PERIOD.
NORTHWESTERLY FLOW TURNS MORE WESTERLY ON FRIDAY AND ANY SNOW
SHOWER ACTIVITIY WILL GRADUALLY DIMINISH...EXCEPT FOR THE EASTERN
MOUNTAINS OF WV. COLDEST TEMPERATURES OF THE SEASON SO FAR ARE ON
TAP AS 85H TEMPS OF -7 TO -12 MOVE IN DURING THE DAY ON FRIDAY.
UNCERTAINY IN THE TIMING OF FORECAST SYSTEMS..AS GFS BRINGS
ANOTHER SHORT WAVE AROUND THE MEAN TROF AND OVER THE REGION ON
FRIDAY NIGHT AND SATURDAY. HOWEVER ECMWF IS SLOWER BUT STILL HAS
SAME WAVE MOVING THROUGH ON SATURDAY. ONLY KEPT SLGHT CHC POPS IN
DUE TO UNCERTAINY. TEMPS WILL HOVER AROUND FREEZING IN THE
LOWLANDS AND 20S IN THE HIGHER ELEVATIONS OF THE EASTERN
MOUNTAINS..AS 85H TEMPS -13 TO -14 RANGE.
MODELS BRING IN HIGH PRESSURE FOR SUNDAY AND MONDAY WITH
TEMPERATURES MODERATING BACK INTO THE 30S AND LOWER 40S.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
MVFR CONDITIONS WITH POST FRONTAL MOISTURE INTO THIS EVENING. LOCAL
IFR IN SHOWERS. AFTER UPPER TROUGH PASSES EAST OF FORECAST AREA
DURING THE NIGHT AND HIGH PRESSURE BUILDS INTO THE REGION FROM THE
SOUTHWEST...CONDITIONS WILL IMPROVE TO VFR REMAINING THAT WAY
TUESDAY.
AFTER 18Z TUESDAY...
IFR POSSIBLE IN RAIN WEDNESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...AAR
NEAR TERM...AAR
SHORT TERM...JMV
LONG TERM...JS
AVIATION...AAR
