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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 101333
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
933 AM EDT MON MAR 10 2014

.SYNOPSIS...
HIGH PRESSURE WILL BE CENTERED OVER THE SOUTHEAST STATES TODAY
WHILE A COLD FRONT MOVES THROUGH THE GREAT LAKES TOWARD NEW
ENGLAND. THE AREA OF HIGH PRESSURE WILL MAINTAIN CONTROL OF THE
WEATHER ACROSS THE MID ATLANTIC REGION THOUGH TUESDAY. MEANWHILE
AN UPPER LEVEL TROUGH WILL BE MOVING THROUGH THE
ROCKIES...RESULTING IN THE DEVELOPMENT OF AN AREA OF LOW PRESSURE
OVER THE CENTRAL PLAINS TUESDAY. THIS LOW PRESSURE SYSTEM IS
EXPECTED TO MOVE EAST...IMPACTING THE WEATHER ACROSS THE EASTERN
UNITED STATES ON WEDNESDAY. HIGH PRESSURE FOLLOWS THIS SYSTEM FOR
THE END OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 930 AM EDT MONDAY...

NO WEATHER WORRIES TODAY. HIGH PRESSURE IS SITUATED TO OUR SOUTH
AND A COLD FRONT IS MOVING THROUGH THE GREAT LAKES. WE WILL RESIDE
BETWEEN THESE TWO WEATHER FEATURES...THE MAIN SIDE EFFECT SHOWING
UP IN THE FORM OF GUSTY WESTERLY WINDS. THE PRESSURE GRADIENT WILL
PERSIST THROUGH TONIGHT...THE WINDS PERSISTING ALONG THE RIDGE
TOPS FOR THE OVERNIGHT TOO.

THE ONLY MOISTURE TO BE FOUND TODAY WILL RESIDE ABOVE 15KFT.
COMBINE THIS WITH THE WESTERLIES ALOFT AND WE WILL LIKELY SEE A
PERSISTENT AREA OF MOUNTAIN WAVE CLOUDINESS ALONG AND EAST OF THE
BLUE RIDGE...ESP FROM VIRGINIA NORTHWARD CLOSER TO THE MOISTURE
SOURCE...THE UPPER LEVEL JET. FOR NOW WILL ENTERTAIN PARTLY SUNNY
CONDITIONS FROM ROA/LYH NORTHWARD...OR DIRTY SUNSHINE.

THE WEATHER AS A WHOLE WILL REMAIN DRY THROUGH THE NEAR TERM. LOW
LEVEL MOISTURE IS NOT TO BE FOUND...AND IF ANYTHING...THE DEEPER
MIXING FROM THE WESTERLY WINDS OVER THE MOUNTAINS WILL BRING DOWN
LOWER DEWPOINTS OR EVEN DRIER AIR FOR THE AFTERNOON. SIMILAR TO
YESTERDAY THE MINIMUM HUMIDITY MAY TEST 20 PCNT DURING THE PEAK
HEATING PART OF THE AFTN WHEN THE LOW LEVEL MIXING IS AT ITS MAX.

TEMPERATURES TODAY WILL BE SIMILAR TO WHAT HAPPENED SATURDAY. 850
MB TEMPS OF +5 TO +7 DEG C SUPPORTING SURFACE TEMPERATURES IN THE
60S...POSSIBLY TESTING 70 IN THE PIEDMONT. LOWS TONIGHT WILL BE
THE COOLEST IN THE VALLEYS...WINDS OVER THE RIDGES KEEPING THE
HIGHER ELEVATIONS WARMER. MODEL GUIDANCE KEEPS ALL LOCAL CLIMATE
STATIONS ABOVE FREEZING TONIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 400 AM EDT MONDAY...

ZONAL WESTERLY FLOW ALOFT WILL RESULT IN VERY MILD TUESDAY ON THE
BACKSIDE OF SURFACE HIGH PRESSURE TO THE SOUTHEAST. THE DEEP
MOISTURE WILL REMAIN TO THE NORTH AND WEST INTO LATE TUESDAY WITH
MID/HIGH CLOUDS LIKELY WITHIN THE WARM ADVECTION AND WITH WEAK
SHEARED ENERGY ALOFT. SHAPED CLOUD COVER TOWARDS THE NAM. HIGH
TEMPERATURES TUESDAY WILL BE ABOVE NORMAL WITH READINGS FROM THE MID
60S IN THE NORTHWEST TO THE LOWER TO MID 70S IN PIEDMONT.

MODELS CONTINUE TO SLOW THE EASTWARD MOVEMENT OF NEXT POTENT
SHORTWAVE PROGGED TO EJECT EAST FROM THE NATIONS MID SECTION.
THUS...SLOWED THE ARRIVAL TIME OF THE MOISTURE TUESDAY NIGHT. LEAD
AREA OF MOISTURE SHOULD BRING SOME SHOWERS IN LATE TUESDAY NIGHT
AFTER 06Z WITH THE MAIN AXIS OF LIFT PASSING ACROSS THE NORTHWEST
WEDNESDAY MORNING...FOLLOWED BY THE PRE-FRONTAL SHRA BAND INTO THE
AFTERNOON. LEANED TUESDAY NIGHT LOW TEMPERATURES TOWARDS THE
ADJMAV WITH VALUES FROM THE LOWER 40S IN THE COLDER MOUNTAINS
VALLEYS TO AROUND 50 ALONG THE SOUTHERN BLUE RIDGE.

A DEEPENING SURFACE LOW TO PASS JUST NORTHWEST OF OUR REGION BY
WEDNESDAY AFTERNOON. WHILE A STRONG COLD FRONT WILL MARCH EAST
PASSING THROUGH THE AREA BY WEDNESDAY EVENING. STRONG DYNAMICS ALOFT
COULD SUPPORT LOW TOPPED CONVECTION WEDNESDAY AFTERNOON MAINLY
ALONG/EAST OF THE BLUE RIDGE MOUNTAINS. SWODY3 HAS ADDED OUR CWA TO
THE THUNDERSTORM OUTLOOK FOR DAY 3 WITH NO SEVERE THUNDERSTORMS
EXPECTED. PLAYED HIGH TEMPERATURES ON WEDNESDAY FROM THE MID 50S IN
THE NORTHWEST MOUNTAINS TO NEAR 70 DEGREES IN THE PIEDMONT.

BEHIND THE FRONT...STRONG CAA WILL RESULT IN TEMPERATURES
PLUMMETING WEDNESDAY EVENING INTO WEDNESDAY NIGHT. WINTRY WEATHER
RETURNS AS RAIN SHOWERS BECOME SNOW SHOWERS AND FLURRIES IN THE
MOUNTAINS. THERE IS POTENTIAL FOR WIND HEADLINES AND FLASH FREEZE.
GUSTY NORTHWEST WINDS ARE POSSIBLE IN THE MOUNTAINS WITH VERY STRONG
PRESSURE RISES WITH THE COLD ADVECTION. AT THIS POINT LOOKS LIKE
WIND ADVISORIES WILL BE NEED ACROSS THE HIGHER TERRAIN WEDNESDAY
EVENING INTO THURSDAY MORNING. THERE IS THE POTENTIAL FOR A FLASH
FREEZE SCENARIO IN THE WEST WHERE SHOULD SEE A DECENT WINDOW OF WIND
BLOWN ACCUMULATING SNOW SHOWERS ESPECIALLY THE NORTHWEST RIDGES
OVERNIGHT. LIGHT SNOW ACCUMULATIONS OF HALF INCH TO 3 INCHES ARE
POSSIBLE WEDNESDAY NIGHT INTO THURSDAY MORNING IN THE FAVORED
LOCATIONS IN THE WESTERN UPSLOPE AREAS. GET YOUR WINTER COATS BACK
OUT FOR WEDNESDAY NIGHT INTO THURSDAY MORNING. LOW TEMPERATURES
WEDNESDAY NIGHT WILL CRASH INTO THE TEENS AND 20S.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 AM EDT MONDAY...

STRONG LOW PRESSURE WILL BE EXITING OFF NEW ENGLAND ON THURSDAY
WITH ONGOING UPSLOPE SNOW SHOWERS WINDING DOWN AS THE DEEP 5H
TROF PIVOTS EAST AND THE COLDEST AIR ALOFT STARTS TO LIFT OUT.
HOWEVER WILL BE QUITE A CHANGE FROM THE EARLIER MILD WEATHER WITH
TEMPS/WINDS MAKING THURSDAY MORE LIKE A MID WINTER DAY VS MID
MARCH.

SNOW SHOWERS CONTINUE IN THE WEST MAINLY DURING THE MORNING...THEN
CUT POPS OFF IN THE AFTERNOON GIVEN FASTER MODEL DRYING. ELSW SHOULD
BE CLEARING OUT UNDER STRONG DOWNSLOPE BUT COLD EVEN IN THE
PIEDMONT. STRONG NW WINDS ALSO A CONCERN INTO EARLY THURSDAY OVER
THE MOUNTAINS WHERE GUIDANCE SHOWS 45-50 KTS AT 85H IN THE WAKE OF A
DEEP DEPARTING UPPER VORT. FOLLOWED CLOSER TO THE SLIGHTLY COLDER EC
MOS TEMPS ESPCLY FAR WEST GIVEN RESIDUAL SNOW/CLOUDS AND MORE WITH
THE SLIGHTLY HIGHER MEX VALUES EAST PER DOWNSLOPE AND ONSET OF
WARMING ALOFT.

BRIEF ZONAL FLOW BEHIND THIS SYSTEM WILL QUICKLY EVOLVE BACK
INTO BROAD UPPER TROFFINESS FOR THE REMAINDER OF THE PERIOD. THIS
WILL ALLOW FOR ANOTHER CLIPPER SYSTEM TO PASS NORTH FRIDAY INTO
SATURDAY WITH A TRAILING COLD FRONT SLIDING SOUTH OF THE AREA BY
SUNDAY. MAY BE ENOUGH MOISTURE NEAR THE BOUNDARY FOR A FEW WESTERN
RAIN/SNOW SHOWERS SAT INTO SAT NIGHT...OTRW DRY THU NIGHT-FRI
NIGHT UNDER EXITING HIGH PRESSURE. HOWEVER WILL BE VERY COLD UNDER
THIS RIDGE FRIDAY NIGHT AS CLEAR SKIES...LIGHT WINDS AND VERY LOW
DEWPOINTS SHOULD SUPPORT TEENS WEST...20S EAST WITH EVEN SOME
SINGLE DIGITS OVER SNOW COVER IN THE DEEPER NW VALLEYS. TEMPS
AGAIN QUICK TO REBOUND WITH READINGS JUMPING BACK TO AT OR ABOVE
NORMAL LEVELS FRIDAY/SAT WITH SOME WARMING ALOFT AND AHEAD OF THE
NEXT FRONT. SLIGHTLY COLDER HIGH PRESSURE RIDGES IN FROM THE NORTH
SUNDAY WITH YET ANOTHER DEVELOPING AREA OF LOW PRESSURE SPREADING
MOISTURE EAST FROM THE SOUTHERN PLAINS BY LATE SUNDAY OR MORESO
SUNDAY NIGHT AT THIS POINT.

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
AS OF 445 AM EDT MONDAY...

VFR THROUGH TUESDAY. THE ONLY WEATHER CONCERN THE NEXT 24 HOURS
WILL BE THE PERSISTENT WESTERLY DOWNSLOPING WINDS OVER THE
MOUNTAINS WHICH MAY RESULT IN SURFACE WIND GUSTS OF 25 KTS AT
TIMES. THE AIRFLOW IS PERPENDICULAR OUR MOUNTAINS...SIMILAR TO
WATER FLOWING OVER A DAM...SO ANTICIPATE THE MOST TURBULENT WINDS
NEAR THE BASE OF THE DAM...OR AT THE BASE OF THE BLUE RIDGE.
MECHANICAL AND MOUNTAIN WAVE TURBULENCE WILL BE MOST PRONOUNCED
FROM KBCB-KROA.

SUB-VFR CONDITIONS RETURN FROM SOUTHWEST TO NORTHEAST LATE
TUESDAY NIGHT THROUGH WEDNESDAY MORNING AS A WARM FRONT LIFTS
THROUGH THE AREA WITH ASSOCIATED RAINFALL. WEDNESDAY AFTERNOON AND
EVENING A STRONG COLD FRONT WILL CROSS THE AREA WITH STRONGER RAIN
SHOWERS AND PERHAPS A FEW THUNDERSTORMS ACROSS THE PIEDMONT.
WEDNESDAY NIGHT INTO THURSDAY...COLD AIR BEHIND THE COLD FRONT
WITH LINGERING MOISTURE MAY BRING SOME SNOW TO THE MOUNTAINS.
ALSO...VERY STRONG WINDS ARE EXPECTED WEDNESDAY NIGHT INTO
THURSDAY BEHIND THE FRONT. BY THIS TIME...ANY SUB-VFR CONDITIONS
WILL BE CONFINED TO THE PREFERRED UPSLOPE AREAS OF SOUTHEAST WEST
VIRGINIA.

BY FRIDAY..HIGH PRESSURE WILL SETTLE OVER THE AREA AND BRING A
DECREASE IN WIND SPEED AND A RETURN TO VFR CONDITIONS FOR THE
ENTIRE AREA.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...PM
NEAR TERM...PM/RCS
SHORT TERM...KK
LONG TERM...JH/KK
AVIATION...PM