Area Forecast Discussion
Issued by NWS Wakefield, VA-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 300014
Area Forecast Discussion
National Weather Service Wakefield VA
714 PM EST Tue Nov 29 2016
A complex weather system over the Midwest and Northeast States will
affect the region through Wednesday night. A cold front approaches
from the west and crosses the Mid Atlantic States Wednesday night.
High pressure slowly builds into the area Thursday through Sunday.
.NEAR TERM /THROUGH WEDNESDAY/...
A weak short wave was producing a band of showers from south
central Virginia to the Lower Maryland Eastern Shore this afternoon.
These will move off to the east-northeast through the rest of the
area into early this evening. QPF is under a quarter inch.
Mid-upper level moisture largely departs early tonight...leaving
lo levels moist. Winds diminish...and potential exists for
low cigs/vsbys developing...esp inland. Otherwise...PoPs to be
20-30% w/lows from 60 to 65.
A second s/w will be tracking NE in SW flow aloft...initially
invof TN/OH Valleys by late tonight...then to the local area by
Wed afternoon. Precipitation chances increase from the west. SPC
has outlooked our area with marginal risk of severe with damaging
winds being the main threat. Most of our area will considerable
cloud cover so instability may be limited, but there will be
moderate shear. For now, have chance for thunderstorms generally
east of Interstate 95 but will need to monitor. High temperatures
warm to around 70 to 75 across most of the area on Wednesday
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
The cold front pushes acrs the area and off the coast Wed ngt into
early Thu morning, with showers and a slgt chc for tstms. Gusty
winds and heavy downpours a possibility with any tstms. Clearing
out fm WNW to ESE later Wed ngt into Thu morning, as WNW flow
behind the front ushers drier air into the region. Lows Wed ngt
will range fm the upper 40s NW to the upper 50s SE.
Dry wx then expected Thu thru Fri, as a dry westerly flow
dominates the area, as high pressure gradually builds toward the
region fm the WNW. Generally mostly sunny both days, with highs on
Thu in the lower to mid 60s, and cooler on Fri with highs in the
lower to mid 50s. Lows Thu ngt will range fm the mid 30s to the
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Cool high pressure is expected to be centered from the
Mississippi Valley through the Southeast Conus Friday night into
Saturday. High pressure builds over the Mid-Atlantic region
Saturday night into Sunday as a split flow pattern develops aloft,
with a srn stream system tracking along the Gulf Coast States, and
a nrn stream wave diving into the Upper Midwest. This will result
in dry conditions under a mainly clear sky, although high clouds
may increase by Sunday. Temperatures are expected to be slightly
below seasonal averages, but within -1 st dev. Forecast lows
Friday night and Saturday night range from the low 30s inland to
the mid/upper 30s along the coast, with highs Saturday/Sunday in
the upper 40s to low 50s. GFS/ECMWF keep the srn stream system
south of the region Sunday night into Monday. However, the ECMWF
is more aggressive with the nrn stream wave, but the net result
may be minimal with respect to sensible weather as the system will
be moisture starved. High pressure returns later Monday into
Monday night, with low pressure approaching from the west during
the Tuesday/Tuesday night timeframe. At this time the 29/12z GFS
is about 12hrs faster than the 29/12z ECMWF.
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Showers have pushed offshore this evening as a weak frontal
boundary resides over the Eastern Virginia Piedmont. Considerable
cloud cover remains over the region, with decks lowering to MVFR
in the Piedmont. Elsewhere, decks are generally 3-5k feet AGL.
Gusty southerly winds have diminished, but a few gusts to around
20 knots observed along the coast. Expect low clouds/stratus to
expand late this evening into late tonight, with widespread IFR
conditions expected by 06-09Z. The exception will be coastal
northeast North Carolina. Guidance still remains pessimistic with
visibilities due to the anomalously moist air mass, but mixing
and stratus will limit the overall coverage of fog. The exception
will be north and west of Richmond and the Maryland Eastern Shore
where winds will diminish below 5 knots. An upper level
disturbance lifting over the region late tonight will bring
scattered light showers to the Piedmont into central Virginia.
Soundings indicate that the stratus will be slow to lift/erode mid
morning Wednesday, but guidance does indicate some drier in the
low levels as a cold front approaches from the west by late
Expect to see some breaks in the clouds Wednesday afternoon with
conditions returning to VFR. Breezy again, with southerly gusts
around 25 to 30 knots. The front pushes across the region
Wednesday night, bringing widespread precipitation to the region.
High pressure slowly builds in through the end of the work week,
resulting in fair weather and VFR conditions.
-- Changed Discussion --Update...SCA flags for Bay (except Mouth), Sound, and Rivers have
been allowed to expire. SCA for the mouth of Ches Bay has been
extended through 1000 PM due to winds continuing to gust around
20kt. Overall, winds will diminish late this evening and overnight
before re-strengthening during Wednesday.
A trough is pushing through the nrn Mid-Atlantic this aftn
resulting in southerly flow of 15-25kt, with gusts up to 30 kt
over the lwr Bay and ocean. The trough lifts newd through New
England tonight with the wind diminishing quickly through the
evening and becoming sw 10-15kt overnight. Waves in the Bay are
generally 3-4ft, with seas ranging from 4-5ft s, to 5-7ft n. Waves
in the Bay subside to 2-3ft tonight. However, seas likely remain
4-6ft. SCAs continue for the Bay/lwr James/Sound through 7 pm,
with flags for the ocean running through Wednesday night to
capture lingering seas and the next southerly surge.
A cold front is expected to push through the Ohio Valley
Wednesday and then push off the Mid-Atlantic Coast late Wednesday
night. The wind should shift to south Wednesday into Wednesday
evening and increase to 15-25kt. It is likely that another round
of SCAs will be necessary for the Bay/Sound/rivers, but will let
the current headlines expire before re-issuing. The wind becomes
westerly at 10- 15kt (minimal CAA) behind the front late
Wednesday night into Thursday. A nw wind of 10-15kt/15-20kt ocean
should prevail Friday into Saturday as high pressure builds across
the Southeast Conus and low pressure persists over Atlantic
Canada. High pressure builds over the region Saturday night into
Sunday. Seas subside from 3-4ft to 2-3ft, with ~2ft waves in the
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-- Changed Discussion --MD...None.
MARINE...Small Craft Advisory until 10 PM EST this evening for ANZ634.
Small Craft Advisory until 6 AM EST Thursday for ANZ650-652-
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