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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 240135
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
935 PM EDT THU MAY 23 2013

.SYNOPSIS...
-- Changed Discussion --
A STRONG COLD FRONT WILL CROSS THE AREA FROM THE NORTHWEST
OVERNIGHT WITH DRIER AND COOLER AIR PUSHING IN FOR FRIDAY INTO
THE WEEKEND. A WARM FRONT WORKS NORTH FROM THE GULF COAST EARLY
NEXT WEEK...FOLLOWED BY STRONG HIGH PRESSURE BRINGING MORE SUMMER
LIKE WEATHER BY MID TO LATE WEEK.
-- End Changed Discussion --
&&

.NEAR TERM /THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 920 PM EDT THURSDAY...

WIND SHIFT FRONT NOW NEARING THE BLUE RIDGE PRECEDED BY A NARROW
LINE OF SHALLOW SHRA/TSRA THAT WILL CROSS THE EASTERN EDGE OF THE
CWA IN THE NEXT HOUR. ACTUAL DEWPOINT FRONT LAGS BACK ALONG THE
OHIO RIVER DENOTED BY ANOTHER BAND OF -SHRA PER REGIONAL RADAR
LOOPS. ONCE THE EASTERN BAND OF SHRA EXITS...MODELS KEEP CLOUDS
PACKED IN ACROSS THE FAR WEST AS THE FLOW TURNS MORE NW WHILE
GETTING MORE CLEARING EAST AS DOWNSLOPE INCREASES LATE. THUS WILL
KEEP CAT/LIKELY POPS OUT EAST A BIT LONGER AND HANG ONTO CURRENT
CHANCES NW SLOPES OVERNIGHT ESPCLY GIVEN THE ARRIVAL OF THE STRONG
5H UPPER SYSTEM TOWARD DAYBREAK.

OVERNIGHT LOWS APPEAR ON TRACK WITH COLD AIR ADVECTION SURGING IN
BEHIND THE SECONDARY FRONT BUT WILL SEE CLOUDS AND MIXING HINDER
BIG DROP IN TEMPS. LOOK FOR LOWS IN THE UPPER 40S ACROSS THE WV
MTNS INTO THE NC MTNS...TO MID 50S NEW RIVER VALLEY/ROANOKE AND
UPPER 50S/NEAR 60 EAST.

MODELS KEEP CLOUDS OVER THE WEST TONIGHT INTO FRIDAY MORNING WHILE
STRONG DOWNSLOPE WORKS TO DRY THINGS OUT TO THE EAST.

PRESSURE RISES ON THE ORDER OF 4-6 MB PER 6 HOURS WILL BE MOVING
INTO THE AREA LATE TONIGHT/EARLY FRIDAY WHERE SOME GUSTS COULD
EXCEED 40 KNOTS. LOW LVL WINDS ARE MARGINAL FOR WIND ADVISORY...BUT
WILL HAVE TO MONITOR TRENDS TO SEE IF AN ADVISORY MAY BE NEEDED OVER
THE HIGHER ELEVATIONS OF FAR SW VA INTO NW NC FRIDAY.

AIRMASS WILL BE NOTICEABLY DRIER AND COOLER FRIDAY WITH THE
BREEZE...WITH HIGHS ONLY MANAGING THE 60S WEST TO LOWER 70S EAST.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 350 PM EDT THURSDAY...

COLD ANOMALOUS UPPER LEVEL TROUGH WILL MOVE ACROSS THE EASTERN CONUS
THIS WEEKEND PROVIDING DOWNRIGHT COOL CONDITIONS FOR THE MEMORIAL
DAY WEEKEND. TEMPERATURES THIS WEEKEND ARE EXPECTED TO BE 15 TO 20
DEGREES BELOW NORMAL WITH AN OPPORTUNITY FOR LOW TEMPERATURES TO
TEST THE 30S BOTH SATURDAY AND SUNDAY MORNING.

1030 MB SURFACE HIGH IS PROGGED TO MOVE ACROSS THE OHIO VALLEY AND
GREAT LAKES FRIDAY...SLIDING SOUTH AND EAST ACROSS THE MID ATLANTIC
REGION SATURDAY AND SUNDAY. COLD AIR ADVECTION RIDING INTO THE AREA
ON BRISK NORTHWEST WINDS FRIDAY NIGHT WILL OVERTAKE THE ENTIRE REGION...DEWPOINTS
SLIPPING INTO THE 20S. IN SPITE OF THE UNSEASONABLY COOL
TEMPERATURES...MIXING FROM THE WIND FRIDAY NIGHT AND ABUNDANCE OF
VEGETATION...ESPECIALLY THE TREE CANOPY...SHOULD TRAP ENOUGH LONG
WAVE RADIATION AT NIGHT TO PREVENT A FROST OR FREEZE. THE ONLY
AREA ATTM THAT WE THINK TEMPS MAY SLIP BLO FREEZING FOR A FEW
HOURS WOULD BE THE WV MTNS NORTHWEST OF LEWISBURG.
ELSEWHERE...UNLESS YOU JUST LIVE IN A DEEP HOLE...UNPROTECTED
MOUNTAIN VALLEY...WOULD THERE BE A NEED TO TAKE ANY PRECAUTION
FROM A FROST OR FREEZE. EVEN IN THESE AREAS...WOULD THINK PLANTS
NEAR BUILDINGS OR UNDERNEATH A PORCH WOULD FAIR JUST FINE.

WITH AIR TEMPERATURES SUPPRESSED WELL BELOW NORMAL FOR THE
WEEKEND...COMBINED WITH LOW DEWPOINTS...A SWIM PARTY AT THE LOCAL
POOL IS NOT RECOMMENDED.  HIKING OR WORKING OUT OF DOORS HOWEVER
LOOK TO BE IDEAL...AS NO RAIN IS FORECAST AND A LOT OF FOLKS MAY
PREFER THE CRISPER COOL CONDITIONS FOR MOWING THE BACK YARD
HAYFIELDS THAT HAVE BEEN PROMOTED FROM ALL THE RAINFALL THIS PAST
WEEK.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 350 PM EDT THURSDAY

LOOKS LIKE WE WILL TRADE THE COOL UPPER TROUGH FOR A MAMMOTH RIDGE
OF UPPER LEVEL HIGH BY THE MIDDLE OF NEXT WEEK.  MONDAY AND TUESDAY
WILL BE TRANSITION DAYS WITH CLOUDS AND POTENTIAL PRECIP SPILLING
INTO THE AREA AROUND AN AMPLIFYING AREA OF UPPER LEVEL HIGH
PRESSURE...WHICH WILL MORPH FROM THE CENTRAL CONUS
MONDAY...OVERTAKING THE EASTERN CONUS BY WEDNESDAY. AT THE
SURFACE...A WARM FRONT WILL MOVE NORTHEAST...UP THROUGH THE OHIO
VALLEY...ARCING THROUGH THE MID ATLANTIC STATES. THIS FEATURE WILL
LIKELY BE THE FOCUS FOR CLOUDS AND POTENTIAL FOR SHOWERS WITH
EMBEDDED THUNDERSTORMS MONDAY AND TUESDAY. THE FRONT SHOULD GAIN
LATITUDE TUESDAY AND FINALLY PUT US COMPLETELY IN THE WARM SECTOR
BY WEDNESDAY. FOR WEDNESDAY AND THURSDAY IT WILL BE BACK TO
REALLY WARM TEMPS AND HIGHER HUMIDITY WITH THE THREAT FOR AIRMASS
SHOWERS AND THUNDERSTORMS MAINLY DURING THE PEAK HEATING HOURS.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
AS OF 725 PM EDT THURSDAY...

LINE OF SHOWERS AND STORMS HAS DEVELOPED ALONG THE BLUE RIDGE AND
WILL BE PUSHING EAST INTO THE PIEDMONT BEFORE WEAKENING IN THE
NEXT HOUR OR TWO. THUS HAVE INCLUDED A COUPLE HOURS OF MVFR IN
CONVECTION FROM KROA EAST WITH WIND GUSTS TO 40 KTS POSSIBLE AS
THIS LINE COMES OFF THE HIGHER TERRAIN. ELSW STILL EXPECTING A
SCATTERING OF SHRA/TSRA ESPCLY SE WVA SITES WHERE WILL KEEP
PREVAILING SHRA AND A VCTS MENTION UNTIL LATE THIS EVENING. LATEST
MODELS SUGGEST MOST COVERAGE SHOULD BE GONE PRIOR TO MIDNIGHT
ALTHOUGH LOWER CLOUDS MAY LINGER IN THE UPSLOPE AREAS AROUND
KBLF/KLWB OVERNIGHT. ALSO WITH SFC WINDS PICKING UP THINK IFR CIGS
AT KBLF A GOOD POSSIBILITY WHILE KLWB DROPS TO MVFR AT TIMES.

FURTHER EAST CIGS WILL BE VFR ALTHOUGH BCB COULD FALL INTO MVFR
FOR A FEW HOURS AROUND DAWN.

WINDS WILL BE PICKING UP IN EARNEST FRIDAY MORNING WITH GUSTS TO
30 KNOTS POSSIBLE ACROSS KBCB/KROA/KBLF. THE DRY AIRMASS SHOULD
BRING ABOUT VFR AT ALL SITES BY THE END OF THE TAF PERIOD.

HIGH PRESSURE TO KEEP US VFR THROUGH THE WEEKEND. MOISTURE
INCREASES AGAIN NEXT WEEK AS THE SFC HIGH MOVES EAST AND THE UPPER
RIDGE STRENGTHENS OVER THE MISSISSIPPI VALLEY. WILL BE GETTING TO
MORE HUMID WEATHER AGAIN WITH SOME THUNDERSTORM THREAT BY TUESDAY
AND FOG ISSUES AT NIGHT IN THE VALLEYS.

&&

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

&&

$$
SYNOPSIS...WP
NEAR TERM...JH/WP
SHORT TERM...PM
LONG TERM...PM
AVIATION...JH/WP