Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wakefield Virginia
344 PM EDT Wednesday Sep 2 2015
a weak trough of low pressure will persist over the middle Atlantic
through Thursday with weak high pressure centered over the Ohio
Valley. Stronger high pressure then slowly drops down from the
northeast states Friday through the weekend.
Near term /until 6 am Thursday morning/...
isolated/scattered rain showers/thunderstorms will continue through this evening as weakening
trough aloft tracks across the forecast area. Expecting trend down in coverage after
01-04z/03. Otherwise...vrb clouds through tonight. Locally heavy rain possible in
any storms. Low temperatures from the u60s-l70s.
Short term /6 am Thursday morning through Saturday/...
weak surface trough lingers over the forecast area...especially eastern half Thursday/Thursday night. After
that...hi pressure aloft amplifies through the Great Lakes and into
the NE Continental U.S. Friday into Sat. Weak boundary will then be settling S
through the mdatlc states Friday afternoon into Sat morning as surface hi pressure
builds S through new eng.
Another summery day Thursday west/ vrb clouds/partly sunny conds. Possibly
enough convergence in vicinity of sea breezes and surface trough for inclusion
of at least slight chance probability of precipitation...mainly afternoon/evening hours. Hi temperatures from the
Partly-mostly cloudy conds expected Thursday night and Friday as surface winds turn
NE resulting in the start of a cooldown. Once again...low confidence
in coverage of precipitation...though will favor highest probability of precipitation inland from the
CST (by Friday aftn). Period of stratus possible Friday night into Sat (mrng) as
winds pick up from the NE...which Ushers in (eventually Sat aftn)
drier air (and gradually clearing - lastly across southern Virginia/NE nc) from
the NE Continental U.S.. hanging onto 20-30% probability of precipitation Friday night into Sat...though
trend in any precipitation expected to be lowering from NE to SW. Also...will likely
be a breezy start to the Holiday weekend...especially eastern portion...W/ ptntl
gusts to 25-30 miles per hour.
Low temperatures Thursday night from the u60s-70s. Hi temperatures Friday in the l/m80s NE to
the u80s-around 90f south-southwest. Hi temperatures Sat from the M/u70s at the CST to
Long term /Saturday night through Wednesday/...
long term period will feature mainly dry weather with surface hi pressure in
the vicinity. For Sat night/Erly sun...NE flow persists across the
forecast area as surface hi pressure centers over the northern middle Atlantic. With some moist
onshore flow did hold onto some slight chance-chance probability of precipitation over southeast
areas Sat night. Temperatures bottom out in the 60s Sat night and reach only
the low/middle 80s Sun afternoon. Flow becomes Ely Monday than southerly by Tuesday and
Wednesday as the hi shifts offshore. This will allow for slowly rising
temperatures each day with highs in the low/middle 80s Monday to middle/upper 80s Tuesday
and Wednesday. Bulk of precipitation is expected to stay S of the area through
this time period with any chance of rain (20%) confined to extreme
southeast Virginia/NE NC.
Aviation /19z Wednesday through Monday/...
VFR conditions early this afternoon at all terminals. Thunderstorms in the
vicinity of kric should move southeastward away from the terminal by
1830z. However...additional showers and thunderstorms are possible in the
22z to 01z time frame...per hi-res models. Have maintained a dry
forecast for the remainder of the 18z tafs...as there is
considerable undercertainty regarding extent of late
afternoon/evening shwrs/tstms. Have inserted some light fog/haze
into kric/kecg/ksby tafs as airmass remains rather stagnant...but
dew points continue to increase. This should allow for fog to
become a bit more widespread than has been the case recently. Kecg
had LIFR conditions this morning...and threat for this occurring
Thursday morning exists.
Outlook...outside of scattered mainly afternoon and evening
showers/thunderstorms Thursday and Friday...dry weather and VFR conditions
are expected through Sunday. Some stratus and fog at some of the
taf sites within a few hours of sunrise Friday morning...with the
potential for some ocean stratus late Friday/Saturday at the
no headlines necessary with this forecast package. Winds remain at or below 10
knots this afternoon into tonight with a weak trough of low pressure over the
area...with waves/seas no higher than 2 feet. Similar pattern and
conds into Thursday with some afternoon seabreezes developing. A backdoor
cold front then drops into the area Friday as hi pressure develops over
the NE states. Pressure gradient tightens up enough into Friday night to
make Small Craft Advisory conds possible over the waters...lasting through Sat and Sat night
as NE flow persists. Winds/waves/seas decrease by sun as the surface
hi weakens and flow becomes more out of the east than NE. Winds then
turn to the southeast then S Monday into Tuesday with sub-Small Craft Advisory conds expected
during this time.