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000
FXUS61 KAKQ 160023
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
823 PM EDT Tue Aug 15 2017

.SYNOPSIS...
Low pressure and an associated weak frontal boundary will slowly
drop south into North Carolina later tonight into Wednesday.
High pressure over the Great Lakes builds into the northeast and mid
Atlantic region Wednesday afternoon into Thursday morning. The
high slides off the coast Thursday afternoon as the next low
pressure systems moves through Ontario. A cold front affects
the local area Friday afternoon into the weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Latest sfc analysis shows a sfc trough of low pressure over
eastern/SE Va with the frontal bndry now rather diffuse over
northern portions of the CWA. Hurricane Gert remains spinning
well off the Carolina coast. Aloft, WSW flow prevails with an
elongated shortwave stretching all the back into TN.

Heavy rain from numerous tstms remains the primary concern
through this evening, with precipitable water values in excess
of 2" and some training/slow moving storms. Appears that the
bulk of the significant heavy rain into early evening will
reside over SE/eastern VA and NE NC, though brief heavy rain and
localized flooding will be possible elsewhere as well. Have
continued mention of a few stronger storms for wind and for localized
flooding in the HWO. As the sfc boundary slowly sags S later
this evening, instability will begin to wane and PoPs drop off
accordingly. After likely PoPs most areas through 00Z, will
begin to see most areas other than far Se VA/NE NC dry out, with
even the SE generally becoming dry by midnight or a little
after. Still warm/humid tonight, but somewhat cooler air filters
in from the N late. Lows range from the upper 60s NW to the mid
70s SE. Have mentioned patchy fog after 06Z over much of the
interior due to today`s rain and light winds.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
For Wed, chances of rain will be much lower, though will
maintain 20-30% PoPs far S (mainly from the VA/NC border S) on
Wed as the frontal boundary lingers not too far S and weak high
pressure builds in from the N. Partly sunny Wed w/ highs upper
80s/around 90F inland...80-85F near the coast. Dry Thu with lows
in the upper 60s to lower 70s, then just a 20-30% chance for
mainly aftn tstms. Highest PoPs west of I-95 across the
Piedmont for any storms developing along the mtns that would
drift east late in the aftn. Otherwise partly- mostly sunny with
highs upper 80s/around 90F. Next front approaches from the W Fri
as low pressure spins over the nrn Great Lakes. Some increase in
moisture may allow for a low chc PoP Fri morning, but the
greater chances will be in the aftn and beyond. Highs Fri upper
80s to lower 90s with higher humidity.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A frontal boundary will slowly drop acrs the region Fri night
into early Mon morning. Will maintain 30-40% Pops for most of
the area fm Fri night thru Sun, and 15-30% Pops for Sun night.
At this time, will go with a mainly dry fcst for Mon thru Tue,
as sfc high pressure builds into the area then off the coast.
Highs will mainly range fm the mid 80s to arnd 90 thru the
period. Lows will range fm the upper 60s to mid 70s.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
The combination of a frontal boundary and deep tropical moisture
is triggering sct showers/tstms across the region this evening.
The latest trends suggests that ECG will have periodic IFR vsby
in heavy rain through 01z, with shra/tsra in vicinity of RIC
through 01z. The front will drop through the area overnight with
the wind becoming NNE. In its wake, abundant low-level moisture
will likely result in IFR stratus at most sites with a lesser
probability at ORF. Vsby is expected to drop to 2-4sm at
RIC/SBY/PHF/ECG. Stratus persists into the morning through about
14z, with gradually improving conditions through the day as weak
high pressure builds into the region. Lingering low-level
moisture and weak flow with high pressure in place will once
again result in the potential for stratus/fog Thursday morning,
with improving conditions Thursday aftn.

A cold front approaches the region Friday and settles over the
region Saturday/Sunday bringing another chance for showers/tstms
Friday through Sunday.

&&

.MARINE...
Late this aftn, Hurricane Gert was located well off the NC
coast and tracking NNE at around 10 mph. Also, a frontal
boundary was laying acrs the area fm west to east. Winds were
generally SE 5 to 15 kt outside of any stronger gusts fm tstms.
Seas will build fm 3 to 4 ft to as high as 5 to 7 ft tonight
into early Wed morning, due to increasing long period (SE)
swells fm Gert.

Otherwise, Gert will move well out into the Atlc late tonight
into Wed night, with sfc high pressure building fm the ern
Great Lakes twd New England. The high will slide off the coast
Thu aftn into Thu night. A cold front will approach fm the west
late Fri. Wind speeds will generally be around 10 kt or less
thru Thu, then generally 10 to 15 kt over the area on Fri.

Given sharp increase in long period swell (10-12 seconds, will
have High Rip risk over southern beaches today...and Moderate
Rip across the north. Will have at least Moderate Risk on Wed.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory for hazardous seas until 7 AM EDT
     Wednesday for ANZ654-656-658.
     Small Craft Advisory for hazardous seas until 2 PM EDT
     Wednesday for ANZ650-652.

&&

$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/MAS
LONG TERM...TMG
AVIATION...AJZ/LKB
MARINE...MAM