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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 010236
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1036 PM EDT THU JUL 31 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE TO OFF THE NEW ENGLAND AND NORTHERN
MID ATLANTIC COASTS TONIGHT. A FRONTAL BOUNDARY WILL DEVELOP
ALONG THE COAST FRIDAY...THEN REMAIN ALONG THE COAST OR JUST
INLAND OVR THE MID ATLANTIC REGION FRIDAY NIGHT THROUGH SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
-- Changed Discussion --
LATEST REGIONAL MOSAIC DEPICTS SCT LIGHT-MODERATE SHOWERS OVER
CNTRL NC THIS EVENING WITH ISOLATED SHOWERS OVER THE CNTRL
APPALACHIANS. THIS IN RESPONSE TO A SHORTWAVE LIFTING OVER THE SE
STATES. RRQ OF DEPARTING 80+ KT UPPER JET ALSO PROVIDING
DIVERGENCE ALOFT. EXPECT THE SHOWERS TO LIFT NNEWD INTO THE ERN VA
PIEDMONT AND CNTRL APPALACHIANS AS THE SHORTWAVE LIFTS OVER THE
REGION. PER LATEST BLENDED PRECIP WATER...PWATS ONLY AROUND 1.2
INCHES. BUFR SOUNDINGS ALSO DEPICTING A RATHER LARGE AREA OF DRY
AIR. HOWEVER...SOME TOP DOWN MOISTENING IS EXPECTED...BUT HIGH
PRESSURE ALONG THE COAST WILL RESULT IN DRY LOW LEVELS. OPTED TO
MAINTAIN 30 POPS FROM THE PIEDMONT INTO CNTRL VA TONIGHT TO
ACCOUNT FOR LIMITED MOISTURE AND DRY LOW LEVELS.
OTHERWISE...MID-UPPER CLOUDS WILL CONTINUE TO STREAM INTO THE REGION
RESULTING IN MOSTLY CLOUDY-CLOUDY SKIES. TEMPS CURRENTLY IN THE
LOW TO MID 70S WITH LOWS STILL PROGGED IN THE MID TO UPPER 60S.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
UNSETTLED/RATHER WET PATTERN WILL DOMINATE THE FCST AREA FRI THRU
AT LEAST SUN...AS TROF ALOFT SITS OVR THE OH/TN/MS VALLEYS WHILE A
FRNTL BOUNDARY SETS UP RIGHT ALONG THE CST OR JUST INLAND OVR THE
MID ATLC REGION. THIS SCENARIO WILL RESULT IN A MOIST SFC-ALOFT
FLO OVR THE AREA. THAT COMBINED WITH GOOD CONVERGENCE/LIFT...ESPLY
WHEN WEAK LO PRES AREAS MOVE NNE ALONG THE FRNTL BOUNDARY...WILL
PROVIDE AN IDEAL SET UP FOR PERIODS OF SHOWERS AND POSSIBLY A
TSTM ALL LOCATIONS FM FRI EVENG THRU AT LEAST SUN. SEVERE WX IS
NOT EXPECTED DURING THIS TIME PERIOD...BUT HEAVY RAINS WILL BE
POSSIBLE...ESPLY OVR ERN/SERN CNTIES...FRI NGT THRU SUN AS PWATS
ARE FCST TO BE BETWEEN 1.75 AND 2.25 INCHES IN THESE AREAS.

PLENTY OF CLOUDS AND LIKELIHOOD OF PCPN WILL HOLD MAX TEMPS DOWN
OVR THE WEEKEND. HIGHS WILL BE MAINLY IN THE UPR 70S TO LWR
80S...WITH LOWS RANGING FM THE MID 60S TO LWR 70S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A STALLED FRONT AND ASSOCIATED PLUME OF ATLANTIC MOISTURE IS
FORECAST TO REMAIN IN VICINITY OF THE ATLANTIC COASTAL PLAIN SUNDAY
NIGHT AND MONDAY. THIS BOUNDARY WILL BE TRAPPED BETWEEN A STRONG
RIDGE OVER THE WESTERN ATLANTIC...AND A TROUGH OVER THE MIDWEST.
THERE ARE SUBTLE MODEL DIFFERENCES AMONGST MEDIUM RANGE
GUIDANCE...WHICH WILL ULTIMATELY AFFECT THE PROBABILITY OF RAIN
DURING THIS TIMEFRAME. 31/12Z GFS REMAINS THE WESTERN-MOST AND HENCE
WETTEST SOLUTION...WHILE THE 31/12Z ECMWF/CMC HAVE THE BOUNDARY
CLOSER TO THE COAST. AT THIS TIME...30-40% POPS (HIGHEST E) WILL BE
MAINTAINED SUNDAY NIGHT AND MONDAY. A COLD FRONT DROPS THROUGH THE
GREAT LAKES MONDAY NIGHT AND TUESDAY...AND THEN INTO THE OHIO VALLEY
BY MIDWEEK. THIS WILL SHOVE THE PLUME OF MOISTURE OFFSHORE...WITH
POPS GRADUALLY DIMINISHING NW-SE THROUGH MIDWEEK. HIGHS SHOULD
AVERAGE IN THE MID 80S MONDAY...AND TREND UPWARD TO THE MID/UPPER
80S TUESDAY...AND UPPER 80S TO AROUND 90 WEDNESDAY/THURSDAY. LOW
TEMPERATURES SHOULD AVERAGE IN THE UPPER 60S TO LOW 70S.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS CONTINUE ACROSS AREA TERMINALS AS HIGH PRESSURE OFF
THE MID ATLANTIC COAST NOSES INTO THE AREA TONIGHT WITH S WINDS AOB
5 KTS. A WEAK DISTURBANCE ROUNDING THE BASE OF AN UPPER LEVEL TROUGH
WILL SLIDE ACROSS THE REGION LATE TONIGHT INTO EARLY FRIDAY. WILL
LIKELY SEE LOWERING CIGS AFTER 00Z. HAVE ACCOUNTED FOR SCT SHRAS
ALONG AND WEST OF KRIC WITH A VCSH MENTION AFTER 06Z. OTHERWISE,
HAVE MAINTAINED A DRY TAF FOR NOW AS COLUMN BEGINS TO SATURATE OVER
THE UPCOMING TAF PERIOD.

OUTLOOK...THREAT FOR SHOWERS/TSTMS INCREASE FRIDAY & CONTINUE INTO
THE WEEKEND AS MOISTURE CONTINUES TO INCREASE ALONG AND AHEAD OF A
STALLED COASTAL BOUNDARY. EXPECT GRADUAL INCREASE IN AREAL
COVERAGE OF SHOWERS SAT/SUN AS MOISTURE RAMPS UP. PERIODIC FLIGHT
RESTRICTIONS WILL BE POSSIBLE IN SHRAS AND TSTMS SAT AFTN AND SUN.

&&

.MARINE...
WEAK HIGH PRESSURE IS SITUATED OFF THE MID ATLANTIC AND NEW ENGLAND
COASTS THIS AFTERNOON...WITH AN INVERTED TROUGH OFF THE SOUTHEAST
COAST. THE INVERTED TROUGH GRADUALLY BECOMES THE DOMINANT FEATURE
LOCALLY LATER TONIGHT INTO FRIDAY...BEFORE SHIFTING INLAND SATURDAY
AND SUNDAY. SUB-SCA CONDITIONS ARE EXPECTED TO PREVAIL THROUGH
SUNDAY. A SOLID 15KT SSE WIND IS ANTICIPATED OVER THE BAY FOR A FEW
HOURS LATE THIS AFTERNOON INTO THE EVENING...BEFORE DIMINISHING
AFTER MIDNIGHT AS THE WIND SHIFTS TO E. AN EASTERLY WIND ~10KT
SHOULD PREVAIL FRIDAY THROUGH FRIDAY NIGHT...BEFORE SHIFTING TO SE
SATURDAY INTO SUNDAY. THE WIND BECOMES S/SW WITH SPEEDS REMAINING
AOB 15KT EARLY NEXT WEEK. SEAS SHOULD AVERAGE 2-3FT...WITH 1-2FT
WAVES IN THE BAY.

&&

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

&&

$$
SYNOPSIS...TMG
NEAR TERM...SAM
SHORT TERM...TMG
LONG TERM...AJZ
AVIATION...MAM/DAP
MARINE...AJZ