Area Forecast Discussion
Issued by NWS Blacksburg, VA

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FXUS61 KRNK 031929
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
329 PM EDT FRI JUL 3 2015

.SYNOPSIS...
A FRONTAL BOUNDARY WILL WORK NORTHEAST THROUGH THE AREA TONIGHT
INTO SATURDAY FOLLOWED BY A COLD FRONT. THE COLD FRONT WILL HANG
UP JUST SOUTH OF US SATURDAY NIGH INTO MONDAY. THIS WILL KEEP OUR
AREA IN AN UNSETTLED PATTERN THROUGH THE HOLIDAY WEEKEND.

&&

.NEAR TERM /THROUGH SATURDAY/...
AS OF 300 PM EDT FRIDAY...

FLASH FLOOD WATCH OVER SE WV INTO THE MOUNTAIN EMPIRE OF SW VA TIL 8
AM SATURDAY. MAIN CONCERN IS SLOWER MOVING/REPEATING SHOWERS WITH
ISOLATED STORMS THROUGH THIS EVENING AS WAVY FRONT REMAINS IN THE
GENERAL AREA. THINK THE LATEST HIGH-RES MODELS SHOWING BETTER RADAR
TRENDS OF TAKING HEAVIER RAIN TO THE NORTHEAST AFTER 03Z...SO THE
WATCH MAY BE CANCELLED EARLY.

THE MODELS SEEM TO BE IN GENERAL AGREEMENT IN THE PATTERN TAKING
WAVY FRONT NORTH OF US SATURDAY MORNING. UNTIL THEN EXPECT SHOWERS
AND SOME THUNDERSTORMS THIS AFTERNOON INTO THE EVENING...WITH ONE
UPPER WAVE PASSING BY. A WINDOW OF SOMEWHAT DRY WX OCCURS OVERNIGHT
BEFORE THE ANOTHER WEAK WAVE MOVES ACROSS THE NC MTNS OVERNIGHT INTO
SATURDAY MORNING. THIS SECOND WAVE ONCE IT MOVES EAST OF US MIDDAY
SATURDAY WILL BE FOLLOWED BY A "COLD" FRONT SATURDAY AFTERNOON.

THIS WILL BE THE FOCUS FOR MORE SHOWERS AND STORMS. GIVEN THE FLOW
TURNS MORE SW THEN WEST THE POPS WERE FOR MORE SCATTERED TO NUMEROUS
COVERAGE AND NOT EVERYONE WILL SEE RAIN SATURDAY BUT HALF TO 3/4 OF
YOU WILL AT LEAST FROM LATE MORNING INTO EARLY EVENING.

WITH CLOUDS AROUND TONIGHT...AND HIGH MOIST SFC CONDITIONS KEPT LOWS
AS WE HAVE HAD THEM THE PAST FEW NIGHTS LOWER TO MID 60S WEST TO
UPPER 60S/NEAR 70 EAST.

MAY SEE SOME SUNSHINE SATURDAY SO HIGHS WILL BE A FEW DEGREES WARMER
THAN TODAY RANGING FROM THE MID TO UPPER 70S WEST TO LOWER OR MID
80S EAST.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 300 PM EDT FRIDAY...

THE UNSETTLED WEATHER WILL CONTINUE INTO THE HOLIDAY WEEKEND.  A WAVE
OF LOW PRESSURE ALONG THE FRONTAL BOUNDARY WILL LIFT NORTHEAST
SATURDAY EVENING INTO SATURDAY NIGHT. THIS WILL PUSH THE FRONT SOUTH
AS LOW CENTER MOVES AWAY FROM OUR AREA. LOW TEMPERATURES SATURDAY
NIGHT WILL RANGE FROM AROUND 60 DEGREES IN THE NORTHWEST MOUNTAINS
TO NEAR 70 DEGREES IN THE PIEDMONT.

THE FRONT GET HUNG UP ON SUNDAY ACROSS THE SOUTH AS CUTOFF LOW TAKES
SHAPE OVER NORTH CAROLINA. WIDESPREAD SHOWERS AND THUNDERSTORMS ARE
LIKELY...BUT THE EXTENSIVE CLOUD COVER WILL HINDER INSTABILITY.
LOCALIZED HEAVY RAINFALL WILL BE THE MAIN CONCERN...BUT GIVEN THAT
THE HEAVIEST RAINFALL SHOULD REMAIN MOSTLY EAST OF THE
MOUNTAINS...THIS FURTHER REDUCES CONCERNS OF FLOODING. WITH CLOUD
COVER AND RAIN...LEANED HIGHS TOWARDS THE COOLER MOS. HIGH
TEMPERATURES SUNDAY WILL BE BELOW NORMAL WITH READINGS FROM AROUND
70 DEGREES IN THE MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT.

THE BEST CHANCE OF CONVECTION SUNDAY WILL BE IN THE EAST. SCATTERED
SHOWERS WILL LINGER SUNDAY NIGHT. LOW TEMPERATURES SUNDAY NIGHT WILL
GENERALLY BE FROM AROUND 60 DEGREES TO THE UPPER 60S.

THE CLOUDY WET WEATHER CONTINUES MONDAY AS THE REMNANT UPPER LOW
DRIFTS INTO NORTHERN VA. THE BEST COVERAGE OF PRECIPITATION WILL BE
LOCATED ACROSS THE EASTERN SECTIONS...BUT DIFFERENTIAL HEATING
ACROSS THE MOUNTAINS SHOULD RESULT IN AN INCREASE OF AFTERNOON
CONVECTION COMPARED TO SUNDAY. WILL HOLD ON TO HIGH CHANCE TO LIKELY
POPS FOR MONDAY. INSTABILITY APPEARS MARGINAL AND THE MAIN CONCERN
WILL REMAIN THAT OF LOCALIZED HEAVY RAINFALL. HIGH TEMPERATURES
MONDAY WILL VARY FROM THE MID 70S IN THE MOUNTAINS TO THE MID 80S IN
THE PIEDMONT.

TAPER OF POPS MONDAY NIGHT INTO TUESDAY MORNING...AS SHOWN ON GFS
AND ECMWF. LOW TEMPERATURES MONDAY NIGHT WILL DROP INTO THE UPPER
50S IN THE NORTHWEST MOUNTAINS TO THE UPPER 60S IN THE PIEDMONT.


&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 PM EDT FRIDAY...

ON TUESDAY...SHORTWAVE ACROSS NORTHERN VIRGINIA WILL LIFT NORTHEAST
TOWARD NEW ENGLAND. AT THE SAME TIME...ANOTHER SHORTWAVE AND
ASSOCIATED FRONT WILL APPROACH FROM THE NORTHWEST TUESDAY. HIGH
TEMPERATURES ON TUESDAY WILL WARM INTO THE LOWER 80S IN THE
MOUNTAINS T0 THE UPPER 80S IN THE PIEDMONT. COLD FRONT PUSHES
SOUTHEAST THROUGH THE OHIO VALLEY...WHILE SURFACE TROUGH WILL PUSH
EAST TO THE ATLANTIC TUESDAY NIGHT. LOWS TUESDAY NIGHT WILL
GENERALLY BE IN THE 60S.

THE FRONT DRIFTS SOUTH WEDNESDAY AND STALLS BY WEDNESDAY NIGHT.
HIGHS ON WEDNESDAY WILL AVERAGE FROM THE MID 70S IN THE MOUNTAINS TO
THE UPPER 80S IN THE PIEDMONT.  THIS BOUNDARY WILL REMAIN ACROSS OUR
REGION THURSDAY INTO FRIDAY NIGHT.

HOW FAR SOUTH THE BOUNDARY GOES IS DIFFERENT DEPENDING ON MODEL
CHOICE. THE ECMWF PUSHING THE COLD FRONT FARTHER SOUTH WITH SOME
SUPPORTIVE UPPER TROUGHINESS COMPARED TO GFS.

ONCE AGAIN WAVES OF LOW PRESSURE ARE EXPECTED TO FORM AND RIDE ALONG
THE FRONT KEEPING A GOOD CHANCES OF DIURNAL SHOWERS AND
THUNDERSTORMS ACROSS THE REGION. HIGH TEMPERATURES FOR THURSDAY AND
FRIDAY WILL MODERATE TO AROUND 80 DEGREES IN THE MOUNTAINS TO THE
MID TO UPPER 80S IN THE PIEDMONT. LOW TEMPERATURES WILL RANGE FROM
MID 60S IN THE MOUNTAINS TO AROUND 70 DEGREES IN THE PIEDMONT.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
AS OF 130 PM EDT FRIDAY...

STABLE LAYER AIRMASS/WEAK WEDGE EXISTS NORTH OF FRONTAL BOUNDARY
OVER THE CAROLINAS. ITS VERY SHALLOW SO EXPECT ANY FOG/LOWER CIGS
TO START TO IMPROVE THIS AFTERNOON WITH MODERATE TO HEAVIER
SHOWERS MOVING IN.

THE TAFS FOLLOWED A BLEND OF THE HIGH RES MODELS HRRR/RAP THROUGH
THIS EVENING...THEN MORE TOWARD THE GFSLAMP AFTERWARDS.

NEEDLESS TO SAY...FLYING WEATHER IS NOT IDEAL THIS HOLIDAY
WEEKEND.

EXPECT MOSTLY SUB VFR CONDITIONS THROUGH THE PERIOD...WORSENING
AGAIN OVERNIGHT WITH IFR OR WORSE POSSIBLE.

BEFORE THIS...TONED DOWN THUNDER THREAT IN THE TAFS AS CLOUD
COVER WILL LIMIT THUNDER THOUGH UPPER DYNAMICS FAVORS SOME
SCATTERED STORMS. FOR THIS KEPT VCTS IN ALL TAFS THROUGH EARLY
EVENING. CONFIDENCE IS HIGHER FOR BLF TO HAVE A SMALL WINDOW OF
THUNDERSTORMS PER RADAR TRENDS FROM 19-21Z.

MODELS START TO LIFT THE SHOWERS AWAY FROM US OVERNIGHT WITH
POTENTIAL FOR LOW CIGS/VSBYS AGAIN WITH FRONTAL BOUNDARY LINGERING
INVOF THE BLACKSBURG FORECAST AREA. WINDS SHOULD TURN MORE SW THEN
WEST BY 14-15Z SATURDAY...WITH CIGS RISING TO AT LEAST MVFR.




EXTENDED AVIATION DISCUSSION...

POOR AVIATION CONDITIONS LIKELY TO CONTINUE INTO EARLY NEXT
WEEK...BUT WINDOWS OF OPPORTUNITY FOR VFR CONDITIONS INCREASE AS
WE MOVE INTO MON/TUE. UPPER LOW/TROUGH WILL LINGER WEST OF THE
VA/NC COASTAL PLAIN INTO THE SOUTHEAST STATES THROUGH THE
WEEKEND...THEN BEGIN TO DRIFT INTO NORTHERN VA BY MON.
MEANWHILE...A COLD FRONT WILL APPROACH FROM THE OH VALLEY BY WED.
THIS LEAVES A VERY UNSETTLED/WET PATTERN ACROSS THE REGION THROUGH
THE PERIOD. EXPECT WIDESPREAD LATE NIGHT/EARLY MORNING LOW
CLOUDS/FOG WITH IFR-LIFR CIGS/VSBYS. OVERALL...CONDITIONS SHOULD
IMPROVE TO MVFR-VFR OUTSIDE SHRA/TSRA ACTIVITY DURING THE
AFTERNOONS. AT THIS POINT...TUESDAY APPEARS TO OFFER THE BEST
OPPORTUNITY FOR MORE WIDESPREAD VFR CONDITIONS.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ007-009>012.
NC...NONE.
WV...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WVZ042>044-507-
     508.

&&

$$
SYNOPSIS...MBS/WP
NEAR TERM...WP
SHORT TERM...KK
LONG TERM...KK
AVIATION...RAB/WP



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