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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 210554
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
154 AM EDT TUE MAY 21 2013

.SYNOPSIS...
LOW PRESSURE ALOFT WILL DRIFT EAST OF THE REGION OVERNIGHT. A
LARGE LOW PRESSURE SYSTEM WILL TRACK FROM THE CENTRAL PLAINS INTO
THE GREAT LAKES BY THURSDAY. THIS SYSTEM WILL PUSH A COLD FRONT
THROUGH THE AREA THURSDAY...FOLLOWED BY HIGH PRESSURE ON FRIDAY.

&&

.NEAR TERM /THROUGH TODAY/...
AS OF 1055 PM EDT MONDAY...

LAST BATCH OF SHOWERS AND STORMS OVER THE CENTRAL CWA DIMINISHED
RAPIDLY A FEW HOURS AGO AND NOW EXPECTING A DRY ALBEIT HUMID
OVERNIGHT PERIOD. AREAS OF FOG LIKELY OVERNIGHT INTO TUESDAY
MORNING ESPECIALLY WHERE RAIN HAS FALLEN. LOW TEMPERATURES CLOSE
TO ADJMAV WITH MILD READINGS FROM THE MID 50S IN THE MOUNTAINS TO
THE MID 60S IN THE SOUTHEAST.

SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ON TUESDAY WITH A
FOCUS ACROSS THE HIGH TERRAIN. LEANED POPS TOWARDS GFS WITH BEST
CHANCE ALONG THE SOUTHERN BLUE RIDGE. KEPT HIGH TEMPERATURES CLOSE
TO WARMER ADJMAV WITH READINGS FROM THE UPPER 70S IN THE MOUNTAINS
TO NEAR 90 DEGREES IN THE SOUTHEAST.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 330 PM EDT MONDAY...

UNSETTLED WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AS AN UPPER
LEVEL TROUGH MOVES FROM THE UPPER MIDWEST TUESDAY...TO THE EASTERN
GREAT LAKES BY LATE THURSDAY.  ASSOCIATED SURFACE FRONT IS EXPECTED
TO PASS THROUGH THE MID ATLANTIC REGION THURSDAY.

SUFFICIENT INSTABILITY FOR AIRMASS THUNDERSTORMS IS EXPECTED
WEDNESDAY WITH FRONTAL SHOWERS AND STORMS THURSDAY. H85 TEMPS OF +15
TO +17 DEG C ARE EXPECTED UP UNTIL THURSDAYS FROPA...SUPPORTING
DAYTIME HIGHS IN THE 80S AND NIGHT-TIME LOWS IN THE 50S/60S. AFTER
THE FRONTAL PASSAGE THURSDAY...TEMPS COOL DOWN THURSDAY NIGHT INTO
FRIDAY.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 345 PM EDT MONDAY...

BOTH THE GFS AND ECMWF ARE DELIVERING A GOOD INTRUSION COOLER AIR BY
12Z FRIDAY WITH H85 TEMPS SLIPPING TO +5C.  THE UPPER TROUGH IS FCST
TO SLIDE ACROSS NEW ENGLAND ON FRIDAY WITH COOL NORTHWEST FLOW
PROGGED FROM THE GREAT LAKES TO THE MID ATLANTIC.

COOLER NORTHWESTERLY FLOW ALSO SUGGESTS THE AIR WILL BE DRY...THUS
HAVE REMOVED ALL MENTION OF PRECIP FOR THE WEEKEND.  THAT SAID...AS
HIGH PRESSURE PASSES OVHD SATURDAY AND ROLLS OFF THE EAST COAST
SUNDAY...MOISTURE COULD SNEAK BACK IN THE PICTURE AS EARLY AS SUNDAY
AFTERNOON.  ATTM...WILL GO WITH AN OPTIMISTIC FCST AND JUST
ADVERTISE INCREASING CLOUDS FOR SUNDAY...AND HOLD OFF ON NEXT
OPPORTUNITY FOR SHOWERS UNTIL MONDAY.

BOTH SATURDAY AND SUNDAY MORNINGS LOOK COOL WITH EARLY MORNING LOWS
IN THE 40S IN THE MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT. IF
WINDS DECOUPLE AND SKIES REMAIN CLEAR...SOME OF THE SHELTERED
MOUNTAIN VALLEYS MAY SLIP INTO THE UPPER 30S.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
AS OF 145 AM EDT MONDAY...

MANY OBSERVATIONS HAVE NOT BEEN TRANSMITTED SINCE 04Z/MIDNIGHT DUE
TO AN OUTAGE IN NATIONAL COMMUNICATIONS CENTER. UNTIL DATA FLOW IS
RESUMED...HAVE ADDED...AMD NOT SKED...TO THE END OF THE TAFS.

EXPECT AREAS OF FOG AND STRATUS OVERNIGHT. IFR TO LIFR CEILINGS
ARE LIKELY BY 09Z/4AM. LOCATIONS THAT HAD RAIN ON MONDAY WILL HAVE
FOG...INCLUDING ROA AND DAN.

A SHORT WAVE OVER THE AREA TONIGHT MOVES INTO EASTERN VIRGINIA
TODAY. ISOLATED TO SCATTERED THUNDERSTORMS WILL DEVELOP AGAIN THIS
AFTERNOON. PROBABILITY AT ANY ONE AIRPORT IS TOO LOW TON INCLUDE
IN THE TAF AT THIS TIME.

THE REGION STAYS IN A WARM...MOIST AIRMASS THROUGH THURSDAY.
PATCHY FOG WITH MVFR VISIBILITIES IS LIKELY EACH NIGHT AND EACH
AFTERNOON AND EVENING THERE WILL BE SCATTERED THUNDERSTORMS.

NEXT FRONT APPROACHES ON THURSDAY WITH MORE SHOWERS/STORMS
DEVELOPING. HIGH PRESSURE AND BETTER FLYING CONDITIONS ARE
EXPECTED ON FRIDAY BEHIND THE FRONT.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...AMS
NEAR TERM...KK/PC
SHORT TERM...PM
LONG TERM...PM
AVIATION...AMS