Area Forecast Discussion
Issued by NWS Wakefield, VA

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FXUS61 KAKQ 022034
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
434 PM EDT THU JUL 2 2015

.SYNOPSIS...
UNSETTLED WEATHER CONDITIONS WILL PREVAIL THROUGH THE HOLIDAY
WEEKEND AS A STATIONARY BOUNDARY LOCATES OVER THE REGION.
DAY TIME TEMPERATURES WILL BE SLIGHTLY BELOW TO NEAR NORMAL.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST REGIONAL RADAR MOSAIC DEPICTS SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS DEVELOPING ALONG A STATIONARY BOUNDARY OVER THE
LOCAL AREA. ANOTHER AREA OF SHOWERS ASSOCIATED WITH A MID LEVEL
SHORTWAVE WAS MOVING INTO THE PIEDMONT AS OF THIS WRITING.
WARM/MOIST AIRMASS IS IN PLACE OVER THE REGION...WITH PWATS CLIMBING
TOWARD 2 INCHES (+2 STD DEV) AND DEWPOINTS IN THE 70S. EXPECT
ACTIVITY TO CONTINUE TO INCREASE THRU THE REMAINDER OF THE AFTERNOON
AS SHORTWAVE ENERGY AND INCREASING WINDS ALOFT PROVIDE FORCING FOR
ASCENT ALONG THE BOUNDARY. HAVE INCREASED POPS LATE THIS AFTERNOON
INTO THE EVENING HOURS TO CATEGORICAL ACROSS THE SRN HALF OF THE
FORECAST AREA. THE MAIN THREAT WILL BE MODERATE TO HEAVY RAINFALL
DUE TO THE ANOMALOUSLY MOIST AIRMASS. CORFIDI VECTORS AND STORM
MOTION SUGGEST THAT STORMS WILL HAVE GOOD FORWARD
PROPAGATION...LIMITING TRAINING CELLS. FFG ALSO RANGES FROM 2-4
INCHES...SO NOT WATCH IS PLANNED ATTM. A MARGINAL RISK FOR SEVERE
WEATHER EXISTS OVER THE REGION...SOUTH OF THE BOUNDARY THIS EVENING.
WEAK LOW-LEVEL AND DEEP SHEAR IS FORECAST OVER THE REGION...BUT
DEEP/RICH MOISTURE COULD CONTRIBUTE TO POTENTIAL FOR WATER LOADING
IN DOWNDRAFTS...MAKING STRONG GUSTY WINDS POSSIBLE. QPF AMOUNTS WILL
RANGE FROM ONE HALF TO ONE INCH RICHMOND SWD...AND LESS THAN HALF AN
INCH NORTH. THIS MATCHES WELL WITH SREF/WPC GUIDANCE.

ANOTHER COMPLEX FORECAST OVER THE KY/TN VALLEYS TONIGHT...PUSHING
EWD THRU THE OVERNIGHT AREAS. MEANWHILE...PRECIP CHANCES EXPECTED
TO PERSIST ALONG THE COAST LATE TONIGHT. THE COMPLEX IS EXPECTED
TO DISSIPATE SOMEWHAT AS IT MOVES OVER THE PIEDMONT AND SRN VA
EARLY FRI MORNING. LOWS TONIGHT IN THE UPPER 60S TO LOW 70S.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
UNSETTLED WEATHER CONTINUES THRU THE SHORT TERM PERIOD AS THE
SURFACE FRONT REMAINS OVER THE MID-ATLANTIC REGION. SHORTWAVE
ENERGY DROPS OVER THE MIDWEST FRI MORNING...TRACKING EWD OVER THE
OH VALLEY FRI AFTERNOON. ASSOCIATED SFC LOW PROGGED TO TRACK EWD
ALONG THE STALLED BOUNDARY...LOCATING OVER THE CENTRAL
APPALACHIANS LATE FRI. A SECONDARY AREA OF LOW PRESSURE LOCATES
OVER CENTRAL NC FRI AFTERNOON. STRONGEST MOISTURE FLUX REMAINS
ACROSS NC...BUT PWATS PROGGED TO REMAIN +2 STD DEV OVER THE LOCAL
AREA. THE RESULT WILL BE ADDITIONAL WIDESPREAD SHOWERS FRI
AFTERNOON AND EVENING. SOME OF THE SHOWERS WILL BE HEAVY AT TIMES.
WILL MAINTAIN A CHANCE FOR THUNDER AS SREF AND NAM GUIDANCE
MAINTAIN MODEST INSTABILITY. DEEP LAYER SWLY FLOW PERSISTS FRI
NIGHT AS SHORTWAVE ENERGY LIFTS ALONG THE OH VALLEY. MAY SEE A
BREAK IN THE PRECIP LATE FRI NIGHT...BUT WILL MAINTAIN SOLID
CHANCE POPS DUE TO THE AIRMASS AND AVAILABLE ENERGY. TROUGH AXIS
LOCATES OVER THE MID-ATLANTIC REGION SAT AS THE SFC LOW RE-
ORGANIZES OVER THE REGION. BEST CHANCES (CHANCE POPS) WILL BE
ALONG THE COAST AS LOW-MID LEVEL FLOW BECOMES WLY. BAGGY TROUGH
REMAINS OVER THE SERN CONUS SUN AS THE FRONT SLOWLY SAGS SWD. THE
RESULT WILL BE ADDITIONAL CHANCES FOR SHOWERS/THUNDERSTORMS SUN
AFTERNOON ACROSS THE SRN AND SERN ZONES. FARTHER NORTH...HIGH
PRESSURE AND DRYING CONDITIONS WILL LIMIT POPS TO SLIGHT CHANCE.

HIGH TEMPS WILL GENERALLY BE IN THE UPPER 70S NORTH TO MID 85 SOUTH
FRI AND SAT...WARMING INTO MID-UPPER 80S SUN WITH LESS PRECIP AND
CLOUD COVER. COOLER ALONG THE COAST. LOWS GENERALLY IN THE UPPER
60S TO LOW 70S.

STORM TOTAL QPF AMOUNTS EXPECTED TO RANGE FROM ONE TO TWO INCHES
ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. THIS IS IN LINE WITH
WPC/SREF QPF AMOUNTS. FLOOD WATCH HEADLINES FOR SAT WILL BE
DEPENDENT ON HOW MUCH RAINFALL THE AREA EXPERIENCE OVERNIGHT
TONIGHT.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE MEDIUM RANGE PERIOD IS CHARACTERIZED BY CONTINUED LOW AMPLITUDE
UPPER TROUGHING OVER THE EASTERN CONUS. EXPECT THAT WITH OCCASIONAL
UPPER DISTURBANCES/PERTURBATIONS PUSHING ACROSS THE REGION, AND WITH
WEAK SFC TROUGH ALONG THE SE COAST THROUGH MUCH OF THE PERIOD, OUR
CURRENT PATTERN OF MAINLY DIURNALLY DRIVEN SHOWERS/STORMS WILL
CONTINUE THROUGH MUCH OF THE FIRST HALF OF NEXT WEEK. HAVE KEPT POPS
IN THE CHC RANGE BY DAY, SLIGHT CHC OR LESS OVERNIGHT. HIGHEST POPS
IN THE PERIOD ARE ON MONDAY WITH QUICK MOVING UPPER SHORTWAVE
PINWHEELING ACROSS THE AREA MONDAY AND MONDAY NIGHT PER BOTH THE
12Z/02 ECMWF AND GFS. FORECAST PW VALUES WILL ALSO REMAIN HIGH
THROUGH THE PERIOD...LINGERING AROUND +2 S.D. ABOVE NORMAL.
ACCORDINGLY, WE`LL NEED TO BE ON GUARD FOR HEAVY RAINFALL WITH
SHOWERS THROUGH THE PERIOD. ADDITIONALLY, WITH THIS INCREASED
HUMIDITY/DEWPOINTS THROUGH THE PERIOD, TOOK A DEGREE OR TWO OFF HIGH
TEMPS MON-WED...GENERALLY FAVORING A TYPICAL MID-JULY
WARM/MODERATELY HUMID SET UP ACROSS THE AREA THROUGH MUCH OF NEXT
WEEK.

&&

.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
WEAK FRONTAL BOUNDARY NOW PUSHING THROUGH CENTRAL VA...WITH
SCATTERED SHOWERS/ISOLATED TSTMS. KSBY HAD TSTMS EARLIER...APPEARS
MORE STABLE UP THAT WAY FOR THE REST OF TODAY/TONIGHT SO WILL KEEP
TSTMS OUT OF THE SBY TAF. ELSEWHERE...SFC FRONT CONTINUES TO DROP
SOUTH THROUGH TONIGHT AND STALL IN FAR SOUTHERN/NORTHERN NC ON
FRI. HAVE GENLY HIT THE LATE AFTN/EVENING TIMEFRAME FOR SHOWERS/TSTMS
AT THE REST OF THE TERMINALS...WITH CIGS LOWERING TO LOW END
MVFR/IFR AFTER 06Z.

THE FNTL BNDRY RMNS OVER MAINLY SOUTHERN VA/NE NC THROUGH THE
WEEKEND WITH CONTINUED CHANCES FOR SHRAS/TSTMS...ESP FRI AFTN/FRI
NGT. HIGHEST CHC FOR MORE SHOWERS/TSTMS BECOMES CONFINED MAINLY TO
SOUTHERN 1/2 OF THE AREA SAT. FRONT LIFTS BACK N ON SUN WITH CONTINUED
CHC FOR SHOWERS/TSTMS...BUT MAINLY VFR CONDS ARE EXPECTED OUTSIDE
OF PCPN.

&&

.MARINE...
UNSETTLED WX CONDITIONS CONTINUE OVER THE WATERS OVER THE
HOLIDAY WEEKEND, AS WK FRONTAL BOUNDARY OVER THE AREA WILL REMAIN NEARLY
STATIONARY OVER THE REGION INTO SAT OVER THE SOUTHERN WATERS. SW
WINDS 10 KT OR LESS S OF THE BOUNDARY...VRB/N-NE WINDS 10 KT OR LESS
ALONG AND NORTH OF THE BOUNDARY. WAVES IN THE BAY AVG 1-2 FT AND
SEAS ON THE COASTAL WATERS AVG 2-4 FT FRI INTO THE WEEKEND WITH SUB-
SCA CONDS TO PERSIST THROUGH THE WEEKEND. THE STALLED FRONT WILL
ALSO RESULT IN SEVERAL EPISODES OF SHRAS/TSTMS INTO SUN. GUSTY
WINDS/HEAVY RAIN WILL BE POSSIBLE IN ANY STORMS THE NEXT FEW DAYS.

&&

.CLIMATE...
JUNE 2015 CLIMATE:

AT NORFOLK:
*AVG TEMPERATURE OF 78.7 F RANKS AS THE 7TH WARMEST ON RECORD.
*TOTAL PRECIPITATION OF 8.34" RANKS AS 5TH WETTEST ON RECORD.

AT RICHMOND:
*AVG TEMPERATURE OF 77.92 F RANKS AS THE 8TH WARMEST ON RECORD.

PRECIPITATION TOTAL OF 6.05" DID NOT ATTAIN A TOP 10 RANKING AT
RIC AIRPORT...BUT MANY LOCATIONS IN THE METRO AREA...RECEIVED IN
EXCESS OF 10.00 INCHES FOR THE MONTH.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...MAS/SAM
NEAR TERM...SAM
SHORT TERM...MAS/SAM
LONG TERM...MAM
AVIATION...ALB/LKB
MARINE...MAM
CLIMATE...



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