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000
FXUS61 KAKQ 120531
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
131 AM EDT Wed Aug 12 2020

.SYNOPSIS...
A trough of low pressure east of the mountains, will increase
the chance for showers and thunderstorms through Friday. A cold
front pushes south across the area Friday night.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 810 PM EDT Tuesday...

Early evening analysis shows coastal trough lingering across
southeastern VA and south across the Carolina coastal plain. To
the west, a diffuse piedmont trough persists over western VA up
into central PA. Showers and T-Storms fired along the shear axis
along the coast of SE VA/NE NC earlier this aftn/evening. Areas
of locally heavy rainfall were observed, with portions of the
eastern Hampton Roads area picking up between 2-4", including a
report of a little more than 2.5" in 90 minutes time in Norfolk.
Flash Flood Warnings in effect for this area have lapsed, but
have maintained an areal flood warning with some lingering
reports of minor flooding from spotters and on traffic cameras
across the region. Farther inland, showers were fewer and
farther between, but some localized heavy rainfall was noted
along and west of the I-95 corridor, which has diminished with
loss of heating. Expect that trend will continue into the
overnight. Might see some isolated/lingering SHRAs over eastern
VA and eastern shore along the trough axis. Otherwise, a partly
cloudy and muggy night is expected w/ poss patchy FG/ST late
into early Wed morning. Lows mainly 70-75F.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
As of 810 PM EDT Tuesday...

Similar setup expected for Wed, as a sfc trough lingers back
near the mountains and hi pres remains in the wrn Atlantic. The
day may begin w/some patchy FG/ST...with some partial clearing
into late morning. Expecting SCT SHRAs/tstms to develop from
midday/early afternoon and continue through the evening hours.
Expect the sfc trough to the west to be the focus for mid-late
aftn and evening storms. Given PWs in the 1.75-2" range, along
with expected low MBE velocities/steering flow for developing
storms, and already diminished flash flood guidance from the
multiple rounds of rains over the past week or so, there is
some concern for a localized flash flood threat. Frequent
lightning and gusty winds are also once again concerns aside
from the heavy rainfall threat. Given the orientation of the
front/sfc trough inland and majority of 12z/11 CAMs depicting
storms/higher QPF more widespread and oriented just to our
N-NW, not confident enough for any flood watches at this time.
However, we will add some more wording to the Hazardous Weather
Outlook for tomorrow over the piedmont and we`ll re-evaluate
late tonight. Highs Wed in the u80s- around 90F...except m80s at
the beaches.

Trough aloft will become established INVOF OH/TN Valleys
Thu-Fri. Tropical moisture will be increasing over the region
leading to a high confidence for SHRAs/tstms. Given the recent
overall wet wx pattern so far this month...flooding will likely
become more of a concern due to PW`s well above normal. Heavy
rain and poss slow movement to the SHRAs/tstms will contribute
to that threat. Otw...mostly cloudy w/ highs Thu in the m80s
then Fri in the l-m80s. Nighttime lows mainly 70-75F.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 120 PM EDT Tuesday...

The extended period will remain unsettled. A slow moving weak
upper level trough from the OH/TN Valleys (Fri night) will
track across the FA this weekend into early next week.
Meanwhile...hi pres will sit nearly stationary over the wrn
Atlantic. Models suggest plentiful moisture through much of the
period and there will likely be a sfc frontal boundary sitting
over the local area (dissipating Mon-Tue). Expecting rather
widespread coverage of SHRAs/tstms from Fri night through the
weekend w/ locally heavy rain and poss flooding. A transition to
more typical Summer conditions (and mainly diurnal pcpn) likely
to occur Mon- Tue. Otw...VRB clouds-mostly cloudy through the
period. Highs Sat/Sun mainly in the l-m80s...lows mainly in the
u60s-l70s. Highs Mon-Tue in the mid-upr 80s.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 130 AM EDT Wednesday...

VFR conditions to start off the forecast period with some patchy
pre-dawn IFR stratus/fog psbl btwn 09Z-12Z. Sct-bkn CU develop
this aftrn as daytime heating combines with a sfc trof east of
the mts. High res data suggests shwrs/tstms develop along this
feature after 18Z. There is also the psblty of some isltd convection
along lcl sea-breezes this aftrn, but activity is not expected to
be as widespread as ystrdy was across sern VA.

Added VCSH at RIC for now where PoPs are the highest. PoPs to low
attm to add any pcpn to coastal TAF sites. Sct convection continues
Wed eve before weakening after midnite. South winds aob 10 kts.

Outlook:
Ptchy late night stratus/BR possible Thurs morning. Shwrs/tstms
become more widespread Thurs thru Sat as moisture increases along
the sfc trof.

&&

.MARINE...
As of 245 PM EDT Tuesday...

Quiet marine conditions continue this afternoon with high pressure
centered well offshore and a weak lee trough in place across inland
areas. Winds are generally southerly between 5-10 knots over the
Ches Bay with winds averaging 10-15 knots offshore. Waves are around
1 foot with seas offshore aob 2 ft.

A modest increase in SSE winds 10-15 knots this evening for the bay
will subside back to 5-10 knots overnight. Expect a similar pattern
to persist Wednesday into Thursday with some potential for mainly
afternoon and evening thunderstorms. Weather becomes increasingly
unsettled Friday into the weekend as a front and weak low pressure
impact the region. A period of onshore/ENE winds is expected in the
wake of the front with the potential for seas to build to 4-5 ft
offshore from late Saturday into early next week.

&&

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

&&

$$
SYNOPSIS...MPR
NEAR TERM...ALB/MAM
SHORT TERM...ALB
LONG TERM...ALB
AVIATION...MPR
MARINE...AJB