Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
920 PM EDT Tuesday Sep 2 2014
a weak cool front drops into the area tonight and settles near the
Virginia North Carolina border Wednesday. High pressure returns
Wednesday night and Thursday.
Near term /until 6 am Wednesday morning/...
latest msas showing cold front apprchg mts with surface trough out ahead
of it east of the mts. Convection that fired up ahead of this trough
is having a Tuff time surviving the trip east as it hits the cap
over the forecast area along with the loss of htng. Even the lone pulse tstrm
that moved across Mecklenburg County dsptd fairly quickly.
Latest models bring main cold front across the forecast area aftr midnight with
only limited moisture given the available warm airmass to work with. Will
keep low chance probability of precipitation through the night given a late night frontal passage. 30
pop northern & western counties....20 pop elsewhere. Warm & muggy. Lows 70-75.
Short term /6 am Wednesday morning through Friday/...
front washes out just south of the area Wed, as upper flow
becomes quasi-zonal and downslope/westerly flow aloft prevails.
Meanwhile, surface high pressure builds over the region on Wednesday as weak
surface trough remains over the southeastern portion of the local area. Given
continued warm/moist and marginally unstable air mass...will
maintain slight chance-low end chance probability of precipitation Wed/Thu...centered
mainly along the trough axis and Theta-E ridge over the southern local
area. Will see a lower rain chance on Friday with no discernible
convective trigger. However, will stick with a slight pop given
plenty of low level moisture and diurnal instability.
Highs remain nearly +1 Standard dev through the short term period,
generally around 90 degree inland and slightly cooler along the
immediate coast. Mild overnight lows generally in the upper 60s
to lower 70s.
Long term /Friday night through Tuesday/...
long term period will feature a return to wetter conditions and
lower temperatures as an upper-level trough and surface cold front approach the middle
Atlantic. For Friday night/Sat morng...with the front still west of the
area expect dry conditions with increasing cloudiness and light S/SW
flow. Rain chances will increase through the afternoon and evening hours Sat as
the front near the area. Probability of precipitation range from 50% northwest to 20% far southeast. Low temperatures
Friday night in the upper 60s to lower 70s with hi temperatures Sat in the upper 80s
to lower 90s.
For sun...increased probability of precipitation to 50-60% as the front sags into southern VA/NC.
A (lwr) chance of rain will continue through early next week with the
front near the Carolina CST and waves of low pressure passing along the
front. As for temperatures...expect highs only in the upper 70s to middle 80s sun
and Monday with the chance of rain and cloud cover...and lows in the
middle 60s to lower 70s.
Aviation /01z Wednesday through Sunday/...
VFR conds prevail at the taf sites with no immediate threat from
convection. A cold front extended from Quebec across western
Pennsylvania and eastern Kentucky to northern Arkansas. This front
is expected weaken as it crosses the Appalachians and reaches
southeast Virginia late Wednesday morning.
Ceilings are forecast to run between 5 and 8 kft as the front
crosses the area. Thunderstorms are expected to be isolated to widely
scattered and did not include in the tafs. Southwest winds of around
10 knots diminish as the front approaches and moves through.
As the front dissipates near the Virginia/NC border Wednesday afternoon...
scattered convection is expected to develop southern portions. This may
impact ecg and orf in the afternoon and evening.
Outlook...afternoon and evening thunderstorms will be possible the next several
days. The highest chances will be on Sunday as the next frontal
system moves through. MVFR/IFR conditions will be possible within a few
hours of sunrise.
sub-Small Craft Advisory conditions will continue this week and into the weekend. Hi
pressure remains offshore this evening with a Lee trough over the middle
Atlantic...leading to southerly winds avgg 10-15 knots over the
Bay/rivers/sound and 15-20 knots over coastal waters. Expect 1-2 feet waves over
the Bay and 2-3 feet seas over coastal waters. A weakening front drops into
the area late tonight into Wednesday morng...veering winds from SW to north. Not
anticipating any headlines at this time due to a lack of cold air advection/surge Post
frontal and a weak pressure gradient. Hi pressure returns Wednesday night through Friday
as sub-Small Craft Advisory conditions continue. Winds shift from north midday Wednesday to the
east/southeast Wednesday night. Winds generally should be east-southeast to S Thursday into Friday at 10-15
knots or less...eventually shifting to the south-southwest Friday ngt/Sat. Next front
moves into the middle Atlantic region over the weekend.
record high temperatures for today 9/2:
Ric: 100/1980 (new record established: 101 f)
orf: 97/1993 (new record established: 99 f)
sby: 97/1980 (tied record)
Today Marks the first time ric has hit 100 since July 8. Last time
ric hit at least 101 was when they hit 102 on 7/8/2012.