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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 160002
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
802 PM EDT Sat Jul 15 2017

.SYNOPSIS...
A frontal boundary stalls near the Virginia North Carolina
border later today into early Sunday. This boundary dissipates
early next week as an upper level trough approaches from the
NW.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Latest weather analysis reveals surface cold front extending
south from surface low pressure just offshore of the S NJ coast.
Slightly drier and not quite as warm across the northern half of
the local area behind the frontal passage, with temps averaging
in the mid to upper 80s to around 90 degrees at 19z. A few
isolated showers have developed ahead of the front across the
eastern Tidewater area this afternoon, with latest CAMs
indicating showers becoming more widespread across NE NC as
showers become more widespread along quasi- stationary frontal
boundary oriented west to east from the mid- south into North
Central/Northeast NC. PW just ahead of the front are still AOA
2" this afternoon, with sfc dewpoints in the low to mid 70s.
This deep moisture in tandem with meager bulk shear values and
h85 winds <10 kts portends to slow-moving heavy rainers with
convection that develops across the southeast late this aftn
through this evening, focused mainly along the sfc trough and
the myriad of remnant convective boundaries from last evening
and early this morning. Have therefore continued likely rain
chances along the NE NC coast from Edenton to Currituck through
the late night hours, and have installed heavy rain mention in
grids to match the HWO. For the record, WPC has nudged day 1
Excessive Rainfall Outlook north to include this same part of
coastal NE NC. Locally heavy rainfall and frequent lightning
again are the primary hazards.

Boundary will become stalled along or just south of the VA/NC
border tonight, with convection gradually diminishing late in
the overnight. Some patchy ground fog possible late over the
coastal areas (MD Eastern Shore/SE VA/NE NC). Partly cloudy
north to mostly cloudy south with lows in the upper 60s
north...low to mid 70s se coast.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
The aforementioned stalled front gradually washes out in place
over the region Sunday morning/aftn. Meanwhile, the upper level
trough will settle along the east coast tomorrow through
Monday. Drier air aloft arriving through the day will allow
conditions dry out across the N, with PoPs of 30-50% continuing
for far SE VA/NE NC in vicinity of the decaying boundary,
tapering back to ~20% for s-central VA to the peninsula. High
temperatures range from the upper 80s to around 90 Sunday, after
morning lows in the upper 60s to mid 70s.

By Monday, low pressure deepens over the ern Great Lakes, thereby
further sharpening the east coast upper trough over the local
area. This should result in at least diurnal convection, focused
mainly along subtle (pre-frontal) lee trough to the west, with
a secondary area of storms possible with seabreeze interactions
along the remains of old boundary over SE VA/NE NC. Continued
low end chance pop over the Tidewater, with a 30-40% pop for
the far NW Piedmont. No real trigger mechanism in between
outside of any convective outflows, so will hold pop at slight
chc (20%) from central VA to the Ern Shore. Highs again in the
upper 80s to around 90 after morning lows of 70-75F.

Next (weak) cool front drops across the area and washes out
in similar fashion Monday night into Tuesday. Expect mainly
diurnally- driven convection associated with numerous weak
shortwaves that push across. After early morning lows in the
70s, look for highs Tuesday again in the upper 80s to low 90s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Bermuda High shifts over the central Atlantic as very persistent
troughing continues across the ern half of the US through the rest
the week. Expect periods of unsettled conditions with showers/storms
developing each aftn/evening. Next best chance for a cold frontal
passage appears to be Fri/Fri night, which would focus thunderstorm
coverage in this timeframe. Otherwise, warm and muggy conditions
will continue with highs generally 90-95F and dewpoints in the
upper 60s NW to around 75F SE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
Expecting primarily VFR conditions through the 00Z TAF period. The
majority of the shower/thunderstorm activity has dissipated and
moved south of the region. There remains a slight chance for a
shower or storm at primarily ECG through the first half of the
night, but the majority of the activity should remain south.
Otherwise, MVFR visbilities may develop overnight as well,
particularly at locations that received the most rainfall today. Any
fog dissipates shortly after sunrise Sunday morning.

Outlook: The front stalls and dissipates near the VA/NC border
through Sunday, maintaining a chance of showers/storms for SE VA/NE
NC. The initial front dissipates by Monday as a trough approaches
from the NW and settles over the area through midweek.
-- End Changed Discussion --

&&

.MARINE...
Sfc cold front is stretched from the Delmarva across far SE VA
towards cntrl NC late this aftn. Isolated thunderstorms have popped
up invof srn Ches Bay (south of New Point Comfort) with more
development anticipated into this evening with plenty of seabreeze
boundaries present as well as a decent temp/dewpoint gradient just
behind the front. Storms are slow-moving and will be highly
proficient at producing very heavy rainfall and isolated gusty
winds. Showers/storms gradually shift swd overnight as the frontal
boundary remains stalled near the VA/NC border into Sunday. The
boundary washes out/dissipates during the aftn, however another
round of isolated to scattered storms will be possible in the
aftn/evening. Bermuda High shifts over the cntrl Atlantic as very
persistent troughing continues across the ern half of the US
through the rest of this upcoming week. Expect periods of
unsettled weather and generally south winds aob 15kt through the
end of the forecast period (Wed night). Seas 2-3ft. Waves 1-2ft.

&&

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

&&

$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...AJZ/MAM
LONG TERM...BMD
AVIATION...AJB
MARINE...BMD