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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 202344
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
744 PM EDT MON MAY 20 2013

.SYNOPSIS...
-- Changed Discussion --
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.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 730 PM EDT MONDAY...

UPPER LOW ACROSS SOUTHERN PORTION OF CWA THIS EVENING WILL
CONTINUE TO MOVE EAST TONIGHT INTO TUESDAY. AFTERNOON CONVECTION
HAD MORE LESS ENDED BEFORE STORMS BEGAN REDEVELOPING THIS EVENING
OVER CENTRAL CWA ALONG SOME TYPE OF BOUNDARY..PSBL OUTFLOW FROM
CHAOTIC COVERAGE THIS AFTERNOON. WILL BE MONITORING NEXT FEW HRS FOR
MAINLY FOR HEAVY RAIN AND POSSIBLE RUNOFF PROBLEMS AND PSBLY
MARGINAL SEVERE.

ALL MODELS HAVE THE BULK OF PRECIPITATION OUT OF THE FORECAST
AREA AROUND MIDNIGHT. PROBABILITY OF PRECIPITATION LOWER FROM WEST
TO EAST OVERNIGHT TO ACCOUNT FOR THIS TREND. AREAS OF FOG WILL
FORM OVERNIGHT INTO TUESDAY MORNING ESPECIALLY WHERE RAIN HAS
FALLEN THIS EVENING. PLAYED 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.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT 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 /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
AS OF 136 PM EDT MONDAY...

STILL EXPECTING THAT CONVECTION WILL WEAKEN WITH THE LOSS OF
HEATING TONIGHT. EXPECTED AREAS OF MVFR/IFR FOG TO DEVELOP
OVERNIGHT ESPECIALLY WHERE RAIN HAS FALLEN...MOST OF TAF SITES
HAVE HAD AT LEAST SOME RAIN TODAY..MOST AT KROA AND KBLF.

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...KK/PC