FXUS61 KRNK 281728
AFDRNK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1228 PM EST SAT NOV 28 2009
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION THIS AFTERNOON AND
TONIGHT...ALLOWING WINDS TO DIMINISH AND A MODERATION IN
TEMPERATURES FOR THE WEEKEND. A COLD FRONT WILL MOVE THROUGH THE
APPALACHIANS EARLY MONDAY...BRINGING A BRIEF PERIOD OF LIGHT RAIN
FOR MOST LOCATIONS. A POTENTIALLY WETTER STORM SYSTEM WILL IMPACT
THE REGION BY MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE WILL BUILD EAST ACROSS OUR AREA TODAY INTO TONIGHT.
THE MID-ATLANTIC REGION IS LOCATED IN A ZONE OF STRONG SYNOPTIC
SUBSIDENCE UPSTREAM OF THE OFFSHORE TROUGH AND DOWNSTREAM OF THE
MIDWEST RIDGE. THICKNESS VALUES WITH FULL SUN SUPPORT HIGH
TEMPERATURES FROM THE LOWER 50S TO AROUND 60. WILL MAKE A FEW MINOR
ADJUSTMENTS IN TEMPERATURES FOR THIS AFTERNOON.
.PREVIOUS DISCUSSION...
WINDS CONTINUE TO DIMINISHING ACROSS EVEN THE HIGHER RIDGES EARLY THIS
MORNING...WITH A FEW GUSTS BETWEEN 20 TO 30 MPH AT THE MOST. THUS WILL
CANCEL THE HIGH WIND WARNING AND WIND ADVISORY BEFORE THE 6AM
EXPIRATION TIME. OTHERWISE...SOME LOW CLOUDS STILL BANKED UP
AGAINST THE UPSLOPE RIDGES IN THE FAR NORTHWEST...AND AS THE UPPER
RDG BUILDS IN THROUGHOUT THE MORNING EVEN THESE SHOULD DISSIPATE BY
SOON AFTER SUNRISE. WITH DRY HIGH PRESSURE IN CONTROL THROUGH
TONIGHT...WILL RESULT IN MAINLY CLEAR SKIES. WEAK SHORT WAVE LIFTING
OUT THROUGH FLAT UPPER RDG TOWARD SUNDAY MORNING MAY BRING A FEW
CIRRUS ACROSS THE SOUTHERN PART OF THE FCST AREA...BUT NOT
EXPECTED TO BE ENOUGH AT THIS POINT TO IMPACT MIN TEMPS.
WITH WARMEST THICKNESSES BUILDING IN ACROSS THE SOUTHWEST
TODAY...SOME LOCATIONS IN THE MTN EMPIRE REGION COULD BE AS WARM OR
WARMER THAN THE NORTHEAST PIEDMONT. NORTH CENTRAL NC PIEDMONT AND SOUTHSIDE
VA WILL BE UNDER SUNNY SKIES AND DOWNSLOPING BREEZES...SO COULD
SEE READINGS INTO THE LOW 60S...BUT FOR NOW ONLY WENT ABOUT 3-4 DEG
ABOVE GUIDANCE...OR AROUND 60. DECOUPLING EXCEPT FOR THE RIDGES
TONIGHT AND GOOD RADIATIONAL COOLING WILL BE BALANCED BY WEAK WARM
ADV AND INCREASES IN DEW PTS SO NOT VERY CONFIDENT THAT TEMPS WILL
BOTTOM OUT BELOW GUIDANCE. ACTUALLY LEANED TOWARD SLIGHTLY WARMER
MET GUIDANCE FOR MINS TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
A HIGH PRESSURE SYSTEM OVER THE SOUTHEAST STATES WILL PUSH EAST OVER
THE ATLANTIC THROUGH SUNDAY NIGHT AS A COLD FRONT APPROACHES THE
REGION MONDAY. LATEST RUN OF THE GFS IS STILL MORE PROGRESSIVE WITH
PUSHING THE FRONT THROUGH BY MONDAY NIGHT WHILE THE ECMWF REMAINS
SLIGHTLY SLOWER. LEANED TOWARD A BLEND OF BOTH MODELS AND HAVE
POPS ENDING BY 12Z TUESDAY.
TEMPERATURES FOR SUNDAY AND SUNDAY NIGHT WILL CONTINUE TO BE MILD
BEFORE THE INFLUENCE OF THE SURFACE FRONT IMPACTS THE FORECAST AREA.
A PUSH OF COLD AIR WILL ARRIVE LATE MONDAY WITH 850MB TEMPS LOWERING
TO +1 IN THE PIEDMONT AREAS TO -7 IN SOUTHEAST WEST VIRGINIA AND THE
ALLEGHANY HIGHLANDS. AS A RESULT OF CLOUD COVER AND COLDER 850MB
TEMPS...HAVE DROPPED MAX TEMPERATURES A COUPLE DEGREES FOR MONDAY
ACROSS THE AREA. MIN TEMPS FOR MONDAY NIGHT WILL AGAIN LOWER TO NEAR
FREEZING WEST OF THE BLUE RIDGE.
BUFKIT SOUNDINGS SUPPORT RAIN CHANGING OVER TO SNOW LATE MONDAY
NIGHT IN THE NORTHWESTERN PORTION OF THE COUNTY WARNING AREA AND
REACHING AS FAR EAST AS THE NEW RIVER VALLEY. MOISTURE IS LIMITED
BUT SHOULD BE ENOUGH TO SQUEEZE A FEW LIGHT SNOW SHOWERS TO THE
GROUND. A FEW LINGERING SNOW SHOWERS ARE EXPECTED THROUGH LATE
MORNING MAINLY IN THE GREENBRIER AND ALLEGHANY HIGHLAND AREA AND
THEN TAPERING OFF BY EARLY AFTERNOON.
HIGH PRESSURE WILL THEN QUICKLY BUILD INTO THE FORECAST AREA
FROM THE WEST IN THE WAKE OF THE COLD FRONT TUESDAY. DRY WEATHER
WILL RETURN FOR TUESDAY AFTERNOON INTO TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
DRY SEASONABLE WEATHER WILL BE BRIEF AS THE NEXT STORM SYSTEM BRINGS
RAIN TO THE AREA WEDNESDAY. A DISTURBANCE WILL MOVE OUT OF THE GULF
AND OVER THE AREA BY WEDNESDAY NIGHT. OVER RUNNING COLD RAIN
SHOULD START WEDNESDAY MORNING ALONG THE VA/NC BORDER...THEN SPREAD
TO THE NORTHEAST THROUGH THE DAY. MODELS STILL IN DISAGREEMENT TO
WHETHER THE UPPER LEVEL LOW IS THE DOMINATE FEATURE MOVING ACROSS
THE OHIO VALLEY...OR THE SURFACE LOW TRACKING ACROSS THE SOUTHEAST
AND OFF THE VA/NC COAST WEDNESDAY/THURSDAY MORNING. EITHER
WAY...MEASURABLE RAIN EXPECTED FOR THE ENTIRE AREA WITH BELOW NORMAL
TEMPERATURES EXPECTED WEDNESDAY. THE BASIC QUESTION TO BE ANSWERED
WILL BE THE AMOUNTS OF RAIN DURING THE EVENT. IF THE SURFACE LOW
DOES DOMINATE...BULK OF THE HEAVIER SHOWERS WILL BE EAST OF THE BLUE
RIDGE AND POSSIBLY NOT IN THE AREA AND MORE TOWARDS THE COAST.
TEMPERATURES ARE EXPECTED TO REMAIN ABOVE FREEZING FOR THIS EVENT TO
BE ALL RAIN. THURSDAY NIGHT INTO FRIDAY...MOISTURE ON THE BACK SIDE
OF THE SYSTEM AND COLD AIR FILTERING IN...COULD PRODUCE A FEW
MOUNTAIN SNOW SHOWERS/FLURRIES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS EXPECTED UNDER NORTHERN NOSE OF HIGH PRESSURE THROUGH
THE NEXT 36 HRS. WINDS MAY STILL BE A LITTLE GUSTY THIS AFTERNOON
ACROSS THE HIGH TERRAIN. RIDGE TOP WINDS IN VCNTY OF TAF SITES MAY
STILL GUST TO 25 TO 30 KTS THROUGH FIRST HALF OF TODAY.
HIGH PRESSURE REMAINS ACROSS OUR AREA THROUGH SUNDAY. NEXT FRONTAL
SYSTEM WILL MOVE INTO THE WEST EARLY MONDAY BUT RAIN IS EXPECTED TO
BE LIGHT THROUGHOUT THE DAY MONDAY. MVFR CIGS/VSBYS CERTAINLY
POSSIBLE..ESPECIALLY AT LWB/BLF...BUT ANY IFR CONDITIONS SHOULD BE
VERY BRIEF. ALSO QUICK PERIOD OF SNOW SHWS AGAIN AT BLF AND LWB
BEHIND FRONT BY MONDAY NIGHT. ANOTHER GOOD CHANCE FOR RAIN BY
MIDWEEK...AND LOOKS LIKE A BETTER CHANCE FOR MORE WIDESPREAD IFR
CONDITIONS WITH THIS SYSTEM.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...SK
NEAR TERM...KK/SK
SHORT TERM...REB
LONG TERM...RCS
AVIATION...KK/SK
