Scientific Forecaster Discussion
fxus61 kakq 240203
Area forecast discussion
National Weather Service Wakefield Virginia
1003 PM EDT sun Jul 23 2017
warm and humid conditions will continue overnight. A weakening
cold front will gradually push across the area on Monday and
stall across the Carolinas through the middle of the upcoming
week. Temperatures will cool down to near normal levels by
Near term /until 6 am Monday morning/...
current analysis indicating weak sfc low pressure centered over
northwest PA, with westerly flow aloft. Coverage of showers/tstms
remains highest in NE NC and far southeast VA, with limited radar
coverage elsewhere. However, an isolated tstm just developed
over western portions of Metro Richmond, and airmass remains
modestly unstable even well after sunset. Have maintained
likely pops over NE NC/southeast Virginia through midnight, with 20-30% most
other areas. Latest high-res/cams have backed off a bot on
coverage of storms after midnight, so have scaled back in the
gridded forecast (but still maintained 40-50% pops along the
coast and generally 20-30% farther inland). Continued warm and
muggy overnight, though areas that received rainfall have cooled
off rather significantly, so lows will range mainly from 70 to
75 f (locally in the upper 70s).
Short term /6 am Monday morning through Wednesday/...
cold front slated to push into northern portions of the forecast area on
Monday while weakening. Deep moisture shifts toward and south
of the Virginia/NC border and therefore will favor highest pops Mon
similarly shifting south across southeast Virginia & NE NC with 20% pops for
the north. Slightly less humid Monday over the northwest County Warning Area. Not quite as
hot, with highs Mon 90 to 95 f over most of the area. This will
preclude the need for additional heat headlines. Front stalls
in NC Tue, with mainly diurnal tstms possible again over the S
(20-35%), and 10-15% north. Seasonable highs upper 80s to lower
90s. Wednesday still looks to be the nicest day we've seen in
awhile temperature-wise. Sfc high pressure traverses New England
with Max temps only reaching the the mid/upr 80s with somewhat
lower humidity levels. Stalled frontal boundary to our south
will still keep a chance of mainly aft/eve shwrs/tstms in the
forecast over our southern forecast area (pops 20-40%).
Long term /Wednesday night through Sunday/...
the mid-Atlantic region will generally be situated between a
trough off the Carolina coast and trough digging through the
Great Lakes and Ohio Valley Wednesday night and Thursday. The
Great Lakes/Ohio Valley trough gradually drops into the region
Thursday night and Friday as an associated cold front approaches
from the northwest. Pops are mainly aob 20% Wednesday night/Thursday
and then increase to 30-40% chc for showers/tstms Friday ahead
of the approaching front. Highs Thursday/Friday are mainly in
the upper 80s to around 90, with mid 80s at the immediate coast,
and overnight lows in the low/mid 70s. The trough is progged to
settle over the region by Saturday/Sunday with the cold front
pushing through Friday night into Saturday, before stalling off
the Carolina coast. Forecast pops for showers/tstms are ~40%
Friday night, and then generally 20-30% northwest to 30-40% southeast next
weekend. High temperatures trend down into the mid 80s as the
trough settles overhead with lows in the upper 60s to low 70s.
Aviation /02z Monday through Friday/...
numerous thunderstorms stretching from central NC to southeast
Virginia moving slowly east. Storms are not affecting any taf
sites but there is a chance for ecg and orf to see some
scattered storms before midnight. Also, a complex of showers and
storms from New York to MD may affect the Eastern Shore MD and sby
before midnight. Showers and/or thunderstorms in the vicinity reflected in tafs for this
potential but don't have strong confidence at this time. Some
patchy fog is possible across the Piedmont during the overnight
but am not expecting any significant impact to taf sites at this
Outlook: convective continues for south central Virginia and NC for
Monday/Tuesday. VFR should dominate through this period, with
periods of sub-VFR possible in heavier showers/tsra. A weak cold
front pushes into the area for the mid week period.
decided to put up Small Craft Advisory for the Chesapeake Bay,
Currituck Sound and for the lower James River. Winds have picked
up over the waters due to increasing pressure gradient. Expect
this to be a short term event until around 4 am. Seas will be 2
feet nearshore and up to 4 feet 20 nm. Showers and
thunderstorms will affect the Lower Bay and Atlantic coastal
waters til around midnight. Winds will remain mostly SW on
Monday but expected to be below Small Craft Advisory criteria.
A frontal boundary crosses the area early Tuesday bringing a
windshift to the E-NE. Winds are expected to generally remain around
15 knots behind the frontal boundary. Seas will range from 2 to 4
feet with some areas to around 5 feet at 20 nm in the far northern
zones. The extended marine period will be dominated by mainly weak
onshore flow as a frontal boundary stalls across the region.
Afternoon showers and thunderstorms will remain possible through the
did not set any records over the past few days (even with the
101 degree temperature reached at ric on sat).
* Date: sun(7/23)
* ric: 103/1952
* orf: 103/2011
* sby: 103/2011
* ecg: 104/1952
Marine...Small Craft Advisory until 4 am EDT Monday for anz630>634.
Small Craft Advisory until 1 am EDT Monday for anz638.