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Area forecast discussion 
National Weather Service Wakefield Virginia
351 am EDT Monday Jul 25 2016

Synopsis...
high pressure prevails over the region through Tuesday. A weak front
drops into the region Tuesday night...then lingers across the region
through most of the week.

&&

Near term /until 6 PM this evening/...
low pres and assctd convection (which prompted the severe warning
for Dorchester county) will move east of the lwr Maryland ern shore
early this morning.

Heat wave to peak today as the broad upper ridge dampens over the
Ohio Valley but remains firmly entrenched over the wrn Atlantic.
1000-500mb thickness values rise to around 5820m over the Piedmont
and 850mb temperatures average around 22-23c across the region. This
easily supports highs in the upper 90s to near 100 across the area
with even lwr 90s at the immediate coast. Dewpoints remain in the
low/mid 70s across most of the fa through peak heating hours. This
results in widespread heat indices between 105 to 110 (highest
across inland portions of southeast Virginia and NE nc). Thus...heat advisory
remains in effect for the entire fa except Maryland beaches where heat
index values peak out around 103.

&&

Short term /6 PM this evening through Wednesday/...
airmass remains capped so no convection expected thru 22z. Isltd
tstms psbl across the nrn most zones this evening due to any Mt
convection that may drift east. Otw...another warm and humid night.
Lows in the mid-upr 70s.

Tuesday starts off dry as the high prs continues to dominate.
Remaining hot as 1000-500mb thickness values only drop to around
5780-5800m and 850mb temperatures drop only to 20-21c. This supports
highs in the mid 90s. Dewpoints remain in the low/mid 70s with heat
indices arnd 105 with heat advisory criteria likely reached again
over the southern two thirds of the fa before any convection
develops. The ridge breaks down enough Tuesday afternoon into
Tuesday evening to allow a weak front to drop into the area and
shortwave energy to cross the mountains. Models a bit faster in
developing tstms across the fa by 18z. Will carry a 30-40% chc of
showers/tstms west of the ches Bay with slght chc pops to the ern
shore. No severe expected but gusty winds and locally hvy downpours
possible in any tstm.

Tstm chcs continue tues nite as the boundary sags south across the
fa. Best support for tstms shifts towards the coast after midnite.
Still warm and humid with lows in the mid/upper 70s.

Westerly flow aloft will allow for the boundary to stall over the
region Wednesday. Enough moisture and support for chc pops across
the area. Highest chc (30-40%) will be from central/S-central Virginia to
se Virginia and NE NC. Highs reach the low 90s under a partly sunny sky.
Dewpoints will be highest across se Virginia/NE NC with heat indices
approaching 105 once again.

&&

Long term /Wednesday night through Sunday/...
stacked high pressure over the southeast coast allows zonal/westerly
flow aloft to settle across the region through the rest of the
week. A series of weather disturbances will pass across the region
as a thermal boundary/Lee trough sets up over the area. This will
provide a focus for thunderstorm development and keep a chance for
storms in the forecast each aftn/evening. Areal coverage fluctuates
with each passing model run and will therefore maintain more
broadbrushed pop grids. Pwats around 2.00-2.25 inches and dewpoints
in the low-mid 70s will result in muggy conditions with ample
moisture present across the area. Factor in weak steering flow
aloft and the anticipated impacts from any thunderstorms will be
locally heavy rainfall and strong gusty winds. Combine the humidity
with temperatures remaining in the lower 90s, and heat indices
will continue to run around 100-104 degrees with a few pockets in
far southeast Virginia/NE NC reaching 105-106 degrees for an hour or two each
aftn. Lows generally in the low-mid 70s inland and mid-upper 70s
beaches.

&&

Aviation /08z Monday through Friday/...
high pressure off the southeast U.S. Coast will once again be the
dominant weather feature today. Other than some MVFR fog at ksby
no visibility restrictions are expected this morng. A dry day
today with SW winds around 10 knots. A few higher gusts are
possible.

Outlook...a cold front drops into the area late Tuesday and then
stalls over northern portions of the mid Atlantic states. A daily
chance for afternoon and evening thunderstorms can be expected
Tuesday through Friday.

&&

Marine...
benign marine conditions expected this week with no headlines
necessary. Fairly stagnant wx pattern continues today with hi
pressure centered off the se coast and a weak trof of lo pressure
over the mid Atlc. Winds will avg 10-15 kt out of the S/SW with
1-2 ft waves over the Bay and 2-3 ft seas over cstl wtrs. There
may be a surge in winds to 15 kt Bay/sound and 15-20 kt coastal
waters tonight ahead of the next cold front, with seas up to 4 ft
over northern coastal waters. This front drops into the area late
Tue/Tue night, and remains in the vicinity thru the end of the
week. There will be a chance of shras/tstms each aftn/eveng.

&&

Climate...
while its certainly going to be hot thru Tue, climatologically
this is the hottest time of the year with several heat waves having
occurred in the past that have been more intense than what we
will experience. No records were set Sunday. The only record high
in jeopardy is today at ecg.

* Record highs:

Records Mon (7/25) Tue (7/26)

* ric: 105 (2010) 100 (1940)
* orf: 105 (2010) 100 (1940)
* sby: 100 (2010) 102 (1940)
* ecg: 97 (1949) 97 (1949)

&&

Akq watches/warnings/advisories...
Maryland...heat advisory from noon today to 8 PM EDT this evening for
mdz021>024.
NC...heat advisory from noon today to 8 PM EDT this evening for
ncz012>017-030>032-102.
Virginia...heat advisory from noon today to 8 PM EDT this evening for
vaz048-060>062-064>069-075>090-092-093-095>100-509>525.
Marine...none.

&&

$$
Synopsis...mpr
near term...mpr
short term...ajz/mpr
long term...bmd
aviation...mas
marine...mas
climate...

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