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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 180220
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1020 PM EDT MON JUN 17 2013

.SYNOPSIS...
-- Changed Discussion --
LOW PRESSURE OVER ARKANSAS WILL MOVE EAST ACROSS THE TENNESSEE
VALLEY TONIGHT AND OVER THE SOUTHERN APPALACHIANS ON TUESDAY.
THIS WILL BRING ADDITIONAL SHOWERS AND STORMS BACK TO THE REGION
TUESDAY INTO TUESDAY NIGHT. WEAK HIGH PRESSURE BUILDS ACROSS THE
AREA WEDNESDAY AND THURSDAY.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 1015 PM EDT MONDAY...

VERY MOIST AIR MASS IN PLACE TONIGHT. ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS WILL CONTINUE OVERNIGHT...ESPECIALLY
WEST OF THE BLUE RIDGE. COVERAGE OF PRECIPITATION WILL INCREASE
AFTER 4AM AS THE SHORT WAVE OVER THE MID MISSISSIPPI VALLEY
APPROACHES THE REGION.

WITH THE RAINFALL THIS AFTERNOON AND SURFACE DEWPOINTS IN THE
LOWER 60S TO LOWER 70S HAVE LEFT AREAS OF FOG IN THE FORECAST FOR
TONIGHT. HAVE RAISED MINIMUM TEMPERATURES BASED ON CURRENT
OBSERVATIONS AND THE LATEST GRIDDED LAMP GUIDANCE. NO CHANGE IN
AIR MASS EXPECTED TONIGHT SO TEMPERATURES WILL REMAIN MILD.

MAIN S/W TROUGH AND ASSOCIATED WEAK COLD FRONT ARE
EXPECTED TO DROP SOUTH ACROSS THE REGION TUESDAY. THE UNSETTLED
WEATHER WITH CONVECTION WILL CONTINUE TUESDAY WITH THE HIGHEST POPS
ACROSS THE SOUTHWEST PORTIONS OF FORECAST AREA. WITH RICH CLOUD
COVER AND PRECIPITATION PLAYED HIGH TEMPERATURES CLOSE TO COOL MOS
VALUES FROM THE UPPER 60S IN THE WEST TO THE LOWER 80S IN THE
SOUTHEAST.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 400 PM EDT MONDAY...

SHORT WAVE WHICH BRINGS PRECIP TO THE AREA TUESDAY WILL EXIT THE
REGION EARLY WED. DRIER AIR WILL WORK ITS WAY INTO THE
REGION...FIRST FROM THE NORTH TUESDAY NIGHT...AND THEN FROM THE
NORTHEAST WEDNESDAY...POPS WANING AS SUBSIDENCE INCREASES ACROSS THE
FORECAST AREA WEDNESDAY.  EASTERLY FLOW IS EXPECTED TO PERSIST INTO
THE DAY THURSDAY...GRADUALLY FADING AND BECOMING LIGHT AND VARIABLE
AS HIGH PRESSURE PASSES OVHD.  ANY PRECIP THREAT FOR THE LATER HALF
OF THE WEEK WILL BE MAINLY CONFINED TO THE MTNS WHERE ENOUGH
CONVERGENCE/DIFFERENTIAL HEATING MAY ALLOW FOR SOME WIDELY SCT
AFTN/EVE SHOWERS IN THE MTNS.  TEMPERATURES WILL REMAIN MOSTLY BELOW
SEASONAL NORMALS THROUGH WED...THEN BEGIN TO MODERATE AS HEIGHTS
BUILD FOR THURSDAY AND BEYOND.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 400 PM EDT MONDAY...

SUBTROPIAL RIDGE IS EXPECTED TO BUILD NORTH...FLOODING THE MID
ATLANTIC REGION WITH WARM TEMPERATURES AND INCREASING DEWPOINTS.
ATTM...NO REAL FOCUS FOR DEEP CONVECTION EXCEPT FOR CONVERGENCE OVER
THE MTNS...SO KEPT ANY PRECIP THREAT MAINLY DIURNAL WITH PRIMARY
TARGETED TO THE MTNS.  TRENDS SUGGEST TEMPS WILL CLIMB BACK ABOVE
NORMAL FOR THE WEEKEND...BUT NOTHING MAJOR...SHOULD NUDGE 90 FOR THE
URBAN AREAS.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
AS OF 730 PM EDT MONDAY...

WIDELY SCATTERED SHOWERS AND THUNDERSTORM WILL CONTINUE THROUGH
02Z. OVERNIGHT...WINDS WILL DIMINISH AFTER SUNSET...BECOMING CALM
IN MANY LOCATIONS. THEREFORE THE USUAL SPOTS...LWB/BCB/LYH...WILL
BE SUBJECT TO RADIATIONAL FOG DEVELOPMENT AS CLOUDS SHOULD REMAIN
MID- HIGH MOST OF THE NIGHT. LWB HAS THE BEST POTENTIAL FOR IFR-
LIFR FG AT THIS POINT. HOWEVER...FOG COULD DEVELOP IN ANY
LOCATIONS WHICH RECEIVES A THUNDERSTORMS THIS AFTERNOON INTO
TONIGHT.

FOR TUESDAY...A STALLED BOUNDARY WILL SERVE AS A FOCUSING
MECHANISM FOR SIGNIFICANT ISENTROPIC LIFT THAT WILL BEGIN IN
EARNEST EARLY TUESDAY. A STRONGER UPPER SHORTWAVE WILL APPROACH
FROM THE NORTHWEST RENEWING SHRA/TSRA ACTIVITY TO OUR
SOUTH...WHICH WILL SPREAD UP/OVER THE REGION TUESDAY...WITH
WIDESPREAD RAIN AS A RESULT. THIS IS NOT EXPECTED TO REACH OUR
SOUTHERN CWA BORDER UNTIL AFT DAYBREAK TUE. OVERALL...WIND SPEEDS
ON TUESDAY WILL BE LIGHT WITH NORTHWEST TO WEST DIRECTION FAVORED
IN THE MOUNTAINS.

MEDIUM TO HIGH CONFIDENCE IN CIGS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH TAF VALID PERIOD.

EXTENDED AVIATION DISCUSSION...CLOUDS ALONG WITH A FEW SHOWERS
MAY LINGER INTO WEDNESDAY BEFORE DRIER AIR BRINGS A RETURN TO
OVERALL VFR THURSDAY INTO FRIDAY...WITH ONLY ISOLATED DIURNAL
MOUNTAIN CONVECTION.

&&

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

&&

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