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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 081704
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1204 PM EST SAT MAR 8 2014

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE ACROSS THE SOUTHEAST STATES WILL MAINTAIN A WARMER
WESTERLY FLOW OF AIR OVER THE AREA THIS AFTERNOON. THE HIGH WILL
WEAKEN AND PASS OFFSHORE TONIGHT AS A WEAK COLD FRONT TO THE
NORTHWEST DROPS SOUTHEAST THROUGH THE MID ATLANTIC REGION BY EARLY
SUNDAY. HIGH PRESSURE SHOULD FOLLOW THE FRONT LATER SUNDAY INTO
TUESDAY AHEAD OF ANOTHER COMPLEX STORM SYSTEM THAT WILL BRING THE
NEXT CHANCE OF PRECIPITATION BY MID WEEK.
-- End Changed Discussion --
&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 930 AM EST SATURDAY...

QUICK TURN AROUND IN STORE THIS AFTERNOON WITH QUITE A WARM UP TO
TAKE SHAPE AS HIGH PRESSURE TO THE SOUTH PROVIDES A WELL MIXED
WESTERLY FLOW OF DRY/MILD AIR ALOFT AHEAD OF THE FRONT TO THE NW.
WILL SEE SOME PASSING BANDS OF HIGH CLOUDS FROM TIME TO TIME
MAKING FOR MORE IN THE WAY OF MILKY SUNSHINE BUT OVERALL MOSTLY
SUNNY. OBSERVED MORNING THICKNESS VALUES SUPPORT HIGHS 57-64 MOST
SPOTS...AND WITH ADDED DOWNSLOPE UNDER THE INCREASING SUN ANGLE
THINK CAN ADD ON A FEW DEGREES IN SPOTS EXCLUDING THE FAR SOUTH
WHERE SNOW COVER MAY HOLD VALUES DOWN A BIT. THUS BUMPED UP HIGHS
ESPCLY ALONG/EAST OF THE BLUE RIDGE WHERE COULD BE A LATE DAY
SURGE INTO THE MID/UPPER 60S. ALSO BUMPED UP WINDS SOME ALONG THE
RIDGES GIVEN THE JET ALOFT THIS MORNING AND GOOD MIXING.

PREVIOUS DISCUSSION AS OF 400 AM EST SATURDAY...

WILL MAINTAIN FREEZING FOG ADVISORY UNTIL 8AM FOR SOUTHSIDE VA
INTO THE PIEDMONT OF NC. TEMPERATURE/DEWPOINT SPREADS REMAIN NEAR
ZERO FROM MARTINSVILLE AND DANVILLE SOUTHWARD INTO NORTH CAROLINA.
AS SUCH...EXPECT THIN SHEEN OF ICE TO DEVELOP ON SURFACES...IN
ADDITION TO UNTREATED ROADS AND SIDEWALKS. ONCE THE SUN COMES
UP...THREAT WILL END.

TEMPERATURES THIS MORNING ARE COOLEST IN THE PIEDMONT WHERE
TEMPERATURES WERE IN THE 20S. READINGS WERE WARMER ACROSS THE
MOUNTAINS...ESP ACROSS THE RIDGE PEAKS...WERE WARM WESTERLY WINDS
WERE KEEPING TEMPERATURES IN THE 40S. THESE WEST WINDS WILL MIX TO
THE SURFACE AFTER SUNRISE...ALL AREAS ACROSS THE CWA PARTAKING IN
WARM CONDITIONS TODAY...WINDS GUSTING 15 TO 20 MPH ATTMS.

SURFACE HIGH PRESSURE...1018 MB...WAS CENTERED OVER ALABAMA THIS
MORNING. A COLD FRONT STRETCHED FROM ONTARIO CANADA THROUGH THE
WESTERN OHIO VALLEY...SOUTHWEST INTO THE STATE OF TEXAS. THIS
FRONT WILL BE APPROACHING OUR AREA TODAY. AS SUCH WE WILL BENEFIT
FROM THE WARM SOUTHWEST FLOW AHEAD OF THE FRONT. 850MB
TEMPERATURES ARE PROGGED AROUND +5 DEG C TODAY. THIS COMBINED WITH
THE ADIABATIC WARMING OVER THE MOUNTAINS FROM THE WESTERLY
DOWNSLOPE WIND SHOULD GIVE US A NICE TEMPERATURE BOOST...MOST
AREAS GETTING WELL INTO THE 50S...AND TESTING 60 FOR A FEW HOURS
MID AFTERNOON.

APPROACH OF THE SURFACE FRONT WILL BRING INCREASING CLOUD
COVER...BEGINNING AS SOME THIN UPPER LEVEL HIGH CLOUDS
TODAY...THEN THICKENING AND LOWERING TONIGHT. THERE WILL BE A BAND
OF RAIN SHOWERS ASSOCIATED WITH THE FRONT...BUT THE EXPECTATION IS
FOR THIS PRECIPITATION TO DRY UP AS IT TRIES TO PASS OVER THE
MOUNTAINS. MODEL QPF IS LESS THAN A TENTH OF AN INCH AND CONFINED
TO OUR WESTERN CWA...OCCURRING MAINLY WEST OF A LWB-MKJ-TNB
LINE...WEST OF LEWISBURG-MOUNTAIN EMPIRE-BOONE. CAN`T RULE OUT A
BRIEF SPRINKLE AS FAR EAST AS THE BLUE RIDGE...BUT THIS WILL
LIKELY BE A NULL EVENT FOR FOLKS EAST OF THE BLUE RIDGE.

THE FRONTAL PASSAGE IS EXPECTED TO PLAY OUT AFTER MIDNIGHT...INTO
EARLY SUNDAY MORNING. CONSIDERABLE CLOUDINESS AND FRONTAL WINDS
SHOULD KEEP THE BOUNDARY LAYER MIXED...SUGGESTING MOST AREAS TO
REMAIN ABOVE FREEZING TONIGHT. THE ONLY EXCEPTION WILL BE THE
HIGHER ELEVATIONS OF WEST VIRGINIA...WEST OF LEWISBURG...WHERE
TEMPERATURES MAY DIP TO 32 DEG F POST FRONTAL. MOST IF NOT ALL THE
PRECIP SHOULD BE OVER WITH BY THAT TIME...SO EVEN FOR THE HIGHEST
ELEVATIONS OF WV...NOT EXPECTING MUCH SNOW SUNDAY MORNING...MAYBE
A DUSTING FOR QUINWOOD...RUPERT...AND RICHWOOD.
-- End Changed Discussion --

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
AS OF 300 AM EST SATURDAY...

A WEAK COLD FRONT WILL DROP SOUTHEAST ACROSS OUR AREA SUNDAY
MORNING. MOISTURE LOOKS QUITE LIMITED WITH THIS BOUNDARY AS IT
PUSHES INTO LOW LEVEL WESTERLY FLOW AND CONFLUENCE ALOFT...WITH BEST
CHANCES ALONG THE WESTERN SLOPES. WEAK LEE TROUGH OUT EAST MAY
PRODUCE AN ISOLATED SHRA EAST OF THE BLUE RIDGE. A DRIER WESTERLY
FLOW EXPECTED BEHIND THE FRONT SUNDAY AFTERNOON INTO MONDAY WITH
WEAK HIGH PRESSURE TO THE SOUTH AND TROFFINESS TO THE NORTH.

A SHORTWAVE DROPS SOUTHEAST MONDAY NIGHT WITH ADDITIONAL CLOUD COVER
ALONG THE WEST SLOPES. THE GFS APPEARS OVERDONE WITH THE LIGHT QPF
IN THE FAR WESTERN SLOPES...COMPARED TO THE NAM AND ECMWF.

HIGH ON MONDAY WILL RANGE FROM THE LOWER 40S IN THE NORTHWEST
MOUNTAINS TO THE LOWER 60S IN THE SOUTHEAST. LOWS SUNDAY NIGHT WILL
VARY FROM THE MID 20S IN THE COLDER MOUNTAINS VALLEYS TO AROUND 40
DEGREES. TEMPERATURES WILL MODERATE ON MONDAY WITH DOWNSLOPE
     WARMING ALOFT AND SUNSHINE. HIGHS MONDAY WILL WARM TO THE MID 50S
IN THE NORTHWEST TO NEAR 70 DEGREES IN THE SOUTHEAST. LOWS MONDAY
NIGHT WILL ONLY DROP INTO THE MID 30S TO AROUND 40 DEGREES. THE
WARMING TREND CONTINUES TUESDAY AHEAD OF THE STRONG COLD LOW WITH
HIGHS TUESDAY FROM AROUND 60 DEGREES IN THE MOUNTAINS TO THE LOWER
70S IN THE SOUTHEAST.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
AS OF 300 PM EST FRIDAY...

BOTH THE ECMWF AND THE EVER IMPROVING CANADIAN...INDICATE A LOW
CENTER AROUND 995 MB WILL PASS JUST TO THE NW OF THE REGION LATE
TUESDAY NIGHT OR WEDNESDAY AFTERNOON...SPREADING A SWATH OF
STRATIFORM RAIN AHEAD OF IT...BEFORE HEAVIER SHOWERS AND PERHAPS A
FEW THUNDERSTORMS DEVELOP AHEAD OF A STRONG COLD FRONT ON WEDNESDAY.
IT`S DEFINITELY GETTING CLOSER TO SPRING WHEN H85 TEMPS CAN FALL
ABOUT 10C IN A 24HR TIMEFRAME...AS VALUES ARE CLOSE TO -15C AT H85
THROUGH SE WEST VA BY 12Z/7A THURSDAY. CONSIDERING THE POTENTIAL
STRENGTH OF THE UPPER WAVE WITH THIS VERY COLD AIR...UPSLOPE SNOWS
GETTING UNDERWAY WEDNESDAY NIGHT MAY PERSIST INTO
THURSDAY...POTENTIALLY WITH ACCUMULATIONS ACROSS SE WEST VA. NEXT
FRIDAY MORNING LOOKS VERY COLD...WITH LOWS POTENTIALLY IN THE TEENS
AT THE COLDEST LOCATIONS. LACK OF HIGH LATITUDE BLOCKING ALLOWS THE
ANOMALOUSLY COLD AIRMASS TO DEPART AS QUICK AS IT ARRIVES...WITH A
MORE TEMPERATE WEEKEND TO FOLLOW.
&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
AS OF 1145 AM EST SATURDAY...

WIDESPREAD VFR CONDITIONS EXPECTED THIS AFTERNOON...PERSISTING
THROUGH ABOUT MIDNIGHT. WEST WINDS MAY INCREASE ACROSS THE RIDGES
WITH HEATING PUSHING GUSTS TO 20-25 KTS AT TIMES THROUGH THE
AFTERNOON. SURFACE COLD FRONT WILL CROSS THE AREA AFTER MIDNIGHT
RESULTING IN MVFR TO PERHAPS OCNL IFR CIGS IN THE MOUNTAINS...MID
AND HIGH CLOUDINESS ELSEWHERE. SCATTERED RAIN SHOWERS WILL
ACCOMPANY THE FRONT OVERNIGHT...BUT THESE SHOWERS ARE EXPECTED TO
DISSIPATE BEFORE THEY GET EAST OF THE MOUNTAINS.

THUS CONTINIUING SUB-VFR CONDITIONS AT KBLF/KLWB...MAINLY AFTER
MIDNIGHT AND PERSISTING THROUGH EARLY SUNDAY MORNING. COULD SEE A
PERIOD OF IFR AT KBLF WITH UPSLOPE FLOW SO INCLUDED A MENTION
OTRW CLIPPED OFF THE MVFR CIGS AT KBCB AND POINTS WEST LATE
TONIGHT. TERMINALS EAST OF THE MOUNTAINS SHOULD REMAIN VFR. EXPECT
PASSAGE OF THE FRONT AND DRIER AIR TO ERODE ANY LOW CIGS BY MID OR
LATE MORNING SUNDAY ALLOWING FOR VFR TO RETURN BY SUNDAY AFTERNOON
INTO SUNDAY NIGHT.

EXTENDED AVIATION DISCUSSION...

VFR CONTINUES FOR EARLY NEXT WEEK BEFORE ANOTHER COMPLEX STORM
SYSTEM APPROACHES FROM THE WEST TUESDAY NIGHT AND
WEDNESDAY...BRINGING THE POSSIBILITY OF WIDESPREAD SUB-VFR. HIGH
PRESSURE FOLLOWING THIS SYSTEM SHOULD PROVIDE A RETURN TO VFR FOR
THE END OF THE WEEK.
-- End Changed Discussion --

&&

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

&&

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