Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
733 PM EDT Monday Sep 1 2014
high pressure builds over the southeastern states through Tuesday.
A weak front drops into the area Tuesday night and settles near
the Virginia North Carolina border Wednesday.
Near term /until 6 am Tuesday morning/...
convection along the surface trough now winding down and should continue
to dspt next few hours with loss of htng. Kept 20-30 pop across the
ches Bay and Eastern Shore areas through the evening. Weak surface ridging
expected to keep most of the area dry tonight. Mostly clear to pt
cloudy and muggy. Lows 70-75.
Short term /6 am Tuesday morning through Thursday/...
mini heat wave culminates tomorrow. 850mb temperatures average
around 20c, which combined with deep mixing and a SW wind of
10-15mph should boost highs into the middle/upper 90s inland with
low 90s along the coastlines. Afternoon dewpoints should mix back
into the middle/upper 60s...which should once again serve to keep
heat indices at or below 100. Forecast highs average around +1.5-2.0 St
dev above seasonal means...and approach but fall just short of
records...which are listed in the climate section below for
reference. Model soundings continue show much of the area to be
well-capped above cumulus bases, and thus have kept a silent pop
through much of the day aside from NE NC along sea breeze. The
approach and passage of a weak cold front late Tuesday night could
trigger a few showers/tstms...but overall coverage should be very
the front washes out over the area, with the surface trough becoming
stalled south of the area Wednesday night, before getting shunted
back north on Thursday in response to upper ridging over the
eastern Continental U.S.. given continued moist airmass, will go with a
20-30% pop each day centered mainly along the trough axis over
the southern third of the County Warning Area...but do expect sky cover to
average out partly to mostly sunny. Highs each day will remain
about a category above normal...but will dropping back to around
90 inland, slightly cooler along the immediate coast. Lows
Tuesday/Wednesday mornings should average in the low/middle 70s.
Long term /Thursday night through Monday/...
long term period will start off with above normal temperatures and
occasional chances for rain. For Thursday ngt/Fri...surface hi pressure centers
offshore with a broad upper-level ridge across the eastern Continental U.S.. did
include a slight chance-chance for a rain showers/thunderstorm (especially over western
areas) closest to the greatest moisture axis and surface Lee trough...but
nothing widespread expected. Temperatures Friday will rise into the upper 80s to
lower 90s under a mostly/partly sky and light southerly winds.
For the remainder of the period...cold front approaches from the west
as an upper-level trough digs across the eastern Continental U.S.. chances for rain
will increase into the weekend as the front drops into the middle
Atlantic. Tough to exactly time the precipitation this far out in
time...but for now will go with a 30-40% chance for rain showers/thunderstorms both
Sat and sun. Hi temperatures ahead of the front Sat will be near
90...dropping into the low to middle 80s on sun with increased cloud
cover and the front in the vicinity.
Aviation /00z Tuesday through Saturday/...
VFR conditions will continue to prevail through the overnight. Moist
atmosphere may lead to MVFR visible Tuesday morning. Winds will generally
be south-southwest-SW at or below 10 knots. High pressure remains anchored over the western
Atlantic through midweek but as a weak surface trough remains over the
region...expect isolated afternoon/evening showers and thunderstorms.
A cold front approaches from the west on Tuesday...crossing the
region late Tuesday night into Wednesday. High pressure returns Thursday
as the front stalls over the Carolinas.
sub-Small Craft Advisory conditions will continue this week. Surface hi pressure remains
anchored over the western Atlantic this evening with a Lee trough over the middle
Atlantic. Resulting southerly flow will average 10-15 knots...with 1-2 feet waves
over the Bay and 2-4 feet seas over coastal waters. Similar conditions into
Tuesday with little change in the pattern. A frontal boundary drops into the
area and weakens Tuesday ngt/Wed...leading to light/vrb winds by late
Wednesday/Wednesday night and seas at or below 3 feet. Not anticipating any headlines at this time
due to a lack of cold air advection/surge Post frontal. Hi pressure returns Wednesday night
through Friday as sub-Small Craft Advisory conditions continue.
record high temperatures for Tuesday 9/2: