Area Forecast Discussion
Issued by NWS Wakefield, VA

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487
FXUS61 KAKQ 281946
AFDAKQ

Area Forecast Discussion
National Weather Service Wakefield VA
346 PM EDT THU JUL 28 2016

.SYNOPSIS...
Strong high pressure will remain off the Southeast coast into the
weekend with a weak frontal boundary lingering to the north of the
area through Friday. This boundary slides south this weekend and
washes out over the area.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A weak frontal boundary stretches from the Delmarva westward into
southern PA and into the Ohio Valley. Meanwhile...a lee trough is
present just to the west of the area. It`s been another hot day
with portions of interior NE NC flirting with excessive heat
warning criteria (>110+ deg). These warm conditions continue into
the evening (unless a thunderstorm develops)...so will maintain
current heat advisory from the RIC metro area south. So far this
afternoon tstm activity has been confined to the lower MD eastern
shore where a couple of SVRs have already been issued. This
activity will tend to weaken and/or move offshore through 5 pm
with interest then turning to activity developing and moving in
from the west. Areas generally along and north of RIC are still
under a slight risk of svr wx this afternoon with the potential
for a svr tstm watch being issued before 5 pm for much of the
area. Instability is certainly there with ML capes of 3000 and
effective shear around 30-40kt. However...still noticing a cap in
place around 800-700 mb layer with only modest mid-level lapse
rates which so far has put a lid on towering cumulus development.
Nonetheless, will continue to carry high chc to likely pops
(50-65%) across northern areas through the evening...and chc pops
25-40% south. Shower and tstm chances later this evening and
overnight will primarily be limited to northern locales, nearest
the weak frontal boundary. Have chc pops north of RIC and kept
things dry across SE VA and NE NC. Lows tonight in the 70s.


&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
The aforementioned weak boundary remains stationary near the
Mason-Dixon line Friday and we`ll wait for the next cold front to
approach from the north by late Friday. Shortwave energy exits the
coast by late morning Friday and puts the local area in a void as
far as convection goes Fri aftn. Therefore, have lowered pops all
areas to slight chc (20%). Not as hot across the north Friday
given the added cloud cover. In additional, we`ll see a small
reduction in dew pts Friday afternoon given better mixing behind
exiting S/W. This should preclude the need for a Heat Advisory
(even in the SE). Highs Friday from the upr 80s north to the
low/mid 90s south. The next cold front sags southward into eastern
VA Friday night it may touch off an isolated shower. Otherwise,
partly cloudy with lows in the low/mid 70s.

That next cold front washes out across the area Saturday/Sunday as
a broad trough aloft takes over. Rain chances this weekend will
generally be diurnally driven and pops were placed at 30-50% for
the afternoon hours. Temps will not be as hot as recent days with
highs from the upr 80s north to the low 90s south.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A cold front finally begins to advance on the Mid Atlantic
Sunday night and is expected to cross the area during
Monday...stalling near the Carolinas into mid week. This
will keep a chance for thunderstorms in the forecast mainly
west of Ches Bay in Ern/Cntrl VA and NE NC Sun night
through Tue night. Meanwhile, sfc high pressure settles
over New England which will result in more seasonal temps
in the upper 80s and cooler dewpoints in the upper 60s to
lower 70s...effectively lowering heat indices into the
lower 90s in the extended forecast periods. In addition,
onshore winds develop by Tue morning and are expected to
persist through the rest of the week...thus having a
drying effect on the overall weather and reducing precip
chances below any mention.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
Mainly VFR conditions across area terminals this morning.
Exception is with some short-lived MVFR at SBY with MIFG/Patchy
ground fog, but expect this to diminish by 28/14z. Otherwise, main
wx maker will be along stationary boundary situated west to east
just to our north across nrn VA and ne MD early this morning. Dry
conditions are expected through midday under sct high clouds, with
scattered showers/tstms developing after 18z. The aforementioned
boundary will remain in vicinity of the Mid-Atlantic region
through Monday resulting in a 30-50% chc of afternoon/evening
showers/tstms through Monday. Best chcs for convection remains
across the northern tier of CWA, mainly along and N of a RIC-SBY
line after 20z. Have held out of TAF for now, with timing still
uncertain...but will likely have to account for areal coverage of
convection with 18Z TAF.

&&

.MARINE...
Low pressure will track along a stationary boundary that is
located just north of the area late this aftn...as strong high
pressure remains anchored off the Southeast Coast. Winds are
generally 10-15kt Bay/coastal waters and 5-10kt rivers/Sound.
Wind directions are variable at the moment due to localized
seabreeze effects in the aftn heat but will become s-sw tonight
due to the boundary to the north. Thunderstorms will become
more widespread through this evening and may be capable of
producing strong wind gusts and large hail. Local seabreeze
boundaries may also create the potential for brief waterspout
development during this time.

A cold front will push through the region Fri and result in a
a wind shift to w during the day and nw Fri night with speeds
remaining 10-15kt. Gusts may reach up to 20kt at best early Fri
morning through mid morning before diminishing to 5-10kt Fri
evening as the front drops south of the area. The front lifts back
to the north Sat into Sat night with the wind becoming se 10-15kt.
The front then settles over the region Sun and stalls near the
Carolina coast through mid week. Seas average 2-3ft through the
period with 1-2ft waves in the Bay.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...Heat Advisory until 8 PM EDT this evening for NCZ012>017-
     030>032-102.
VA...Heat Advisory until 8 PM EDT this evening for VAZ060-065>069-
     078>090-092-093-095>098-513>516-518-520-523>525.
MARINE...None.

&&

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



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