Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 291807
Area Forecast Discussion
National Weather Service Wakefield VA
107 PM EST Tue Nov 29 2016
A complex weather system over the Midwest and Northeast States will
affect the region through Wednesday. 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 /UNTIL 6 PM THIS EVENING/...
Made adjustments mainly to POPs for the rest of the day based on
current trends. The CWA has become warm sectored and precipitation
has decreased in coverage. Winds will be quite breezy from the south
with gusts to 25 to 30 mph in open areas.
As a weak upper level impulse moves through have precipitation
increase slightly midday and early afternoon across central and
eastern Virginia. Have a chance for showers north of a line from
Emporia to Newport News with mainly dry weather continuing to the
south. Have likely POPs through early mid afternoon north of a
line from Farmville across the northern neck to Salisbury.
Precipitation amounts will be no more than a tenth to a quarter
inch with highest amounts to the north.
Knocked temperatures down slightly due to the effect of cloud
cover but it will still be quite mild. Most locations reach the mid
to upr 60s with some lower 70s over far soutnern Virginia and
northeast North Carolina.
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Mid-upper level moisture largely departs early tonight...leaving
lo levels moist. Winds to lower...and potential exists for lo
cigs/vsbys developing...esp inland. Otherwise...PoPs to be 20-30%
w/ lows in the u50s-l60s.
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. Modest instability at best ahead of that system by
Wed afternoon...mainly E of I 95. Developing area of shras
expected over the higher terrain to the W Wed morning...which
spreads to the E by late Wed. Potential for moderate/heavy RA and
isold T the farther E the systems gets. Highest PoPs W and
central locations Wed...then shifts E by late Wed evening.
Otherwise...mostly cloudy inland (highs Wed in the u60s-around
70F)...VRB clouds at the coast (highs Wed in the l-m70s).
After shras/possible isold T in the evening (highest PoPs E of I
95)...clearing out W-E after midnight Wed night. Lows in the u40s
W to u50s at the coast.
Cooler/dry wx expected Thu w/ WNW winds. Sunny to partly cloudy w/
highs in the m-u50s...except l60s in far SE VA-NE NC.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
The extended period is expected to begin with cool high pressure
gradually building across the Southeast Conus. This will result in
dry conditions, with temperatures slightly below seasonal
averages, but within -1 st dev. Sky cover is expected to be mostly
clear, however, increasing high clouds are possible Saturday.
Forecast lows Friday morning range from the mid 30s to around 40,
followed by highs Friday in the low/mid 50s. Slightly cooler
Friday night and Saturday with lows ranging from the low 30s
inland to the mid/upper 30s along the coast, and highs around 50.
There is the potential for highs to remain in the 40s Saturday if
thicker high clouds arrive earlier. GFS/ECMWF diverge Saturday
night through Sunday night, with the GFS depicting a progressive
nrn stream wave tracking across the region, while the ECMWF shows
a phased system lifting ne through the Ohio Valley. At this time
forecast PoPs are ~30%, which is slightly above climo. Model
differences continue into Monday, but the consensus is for a drier
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --A weak upper level impulse will bring scattered showers across
eastern Virginia and the Lower Maryland Eastern Shore this
afternoon. The precipitation will move off to the northeast by early
this evening. South winds will gust to around 20 to 25 knots through
the afternoon. An abundance of low level moisture will result in low
ceilings and visbilities at the TAF sites with highest confidence
over inland northern portions. Visibilities are expected to go no
lower than one mile but widespread IFR or LIFR ceilings are likely.
Conditions will be slow to improve Wednesday morning with plenty of
cloud cover and a low sun angle. It is possible that SBY and RIC
will remain IFR through 18Z. The forecast is for mainly dry
conditions overnight through 18Z Wednesday with only small chances
for showers at SBY and RIC.
OUTLOOK...As low clouds lift Wednesday afternoon...the chance for
showers increases Wednesday afternoon and night with a chance for
thunderstorms southeast portions. Mainly MVFR conditions are
indicated with short periods of IFR possible. Following a cold
frontal passage Wednesday night...the weather improves by Thursday
morning. VFR and dry conditions are forecast Thursday through Sunday
as high pressure slowly builds in from the west.
-- End Changed Discussion --
A trough pushing through the Ohio Valley will cause an increase
in wind speeds across the marine area today, reaching 15-25kt with
gusts up to 30 kt over the ocean. Waves in the Bay build to 3-4ft,
with 5-7ft seas in the ocean (highest n). The trough lifts newd
through New England tonight with the wind becoming sw to w and
diminishing to 10-15kt. Waves in the Bay subside to 2-3ft.
However, seas remain 4-6ft. SCAs for the Bay/Rivers/Sound come
down by 7 pm.
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 the 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, while seas may not
drop below 5ft (especially n) between the two events. Therefore,
have extended SCAs for the ocean into Wed night. The wind becomes
westerly at 10-15kt (minimal CAA) behind the front late Wednesday
night into Thursday as the front shifts offshore. A nw wind of
10-15kt should prevail Friday into Saturday as high pressure
builds across the Southeast Conus. Seas subside from 3-4ft to
2-3ft, with ~2ft waves in the Bay.
MARINE...Small Craft Advisory until 4 PM EST this afternoon for
Small Craft Advisory until 7 PM EST this evening for
Small Craft Advisory until 6 AM EST Thursday for ANZ650-652-