Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 172047
Area Forecast Discussion
National Weather Service Wakefield VA
347 PM EST Tue Jan 17 2017
A weak warm front lifts through the area this afternoon, as low
pressure tracks east from the Great Lakes to New England. A
cold front pushes off the Mid Atlantic coast Wednesday morning.
High pressure then builds in from the west by Wednesday night
and settles over the area on Thursday. The high slides off the
coast Thursday night as another front moves in by Friday.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Latest analysis shows ~1008 mb sfc low pressure over Michigan,
with strong high pressure centered over eastern Canada, ridging
SW to off the mid-Atlc coast. Sfc warm front is becoming somewhat
ragged/disorganized to our S and W but weak resemblance of the
warm front slides through the area into early aftn. Radar
showing 1st batch of light rain moving off to the ENE now
confined mainly from the middle Peninsula/northern Neck to the
eastern shore. A brief 30-60 minutes of partial sunshine will
occur across much of VA W of the Bay, but this should rapidly
fill back in as another area of showers/light rain is developing
over south central VA and will push to the E/NE over the next
few hrs. In general, rain amounts will continue to be very light
(and thus far have only been a few hundredths). Still, will
maintain likely to categorical POPS over northern sections of
the CWA into early aftn, tapered to just a 20% POP over
northeast NC. By mid-late aftn will carry a more broad-brushed
high chc to low-end likely POP for all zones. Temperatures as
of 16Z avg in the upper 40s to lower 50s. With increasing SSW
low level flow, expect to see highs over most of the CWA in the
mid 50 to around 60 F (but will range from the lower 60s over
the far south to the lower- mid 50s over the eastern shore).
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
After perhaps a few hrs of a lull early, POPS ramp back up this
evening as a cold front approaches the region from the W.
Strong shortwave passes by from 09-15Z/Wed. Best lift and
moisture convergence looks to reside over the eastern shore this
evening, then with a line of showers pushing S overnight into
wed morning. Will carry 30-50% POPS well inland, with likely
POPS/60% closer to the coast. Cold Front passes through
Wed...and with deeper mixing and WNW flow in low levels...should
see skies turn partly to mostly sunny late along with a warm
day with highs at least in the mid 60s. Showers will be most
likely across the E and SE where drier air is slower to arrive.
Dry/mostly clear Wed night and Thu as sfc high pressure settles
over the area. Lows Wed night in the mid/upr 30s inland to the
lwr 40s far SE. Highs in the 50s Thu.
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A series of low pressure systems will lift northeast from the
Southern Plains during the long term period. This pattern will keep
temperatures above normal for the long term along with a few rounds
of precipitation. The timing of the precipitation has been moved a
little earlier than the previous forecast.
The first system will move through in the form of an upper level
short wave Friday with likely POPs except 50 percent POPs for the
northeast North Carolina counties. The precipitation ends from
southwest to northeast late Friday and Friday evening. The next
system will be stronger with a cutoff upper over the Mississippi
Valley and associated deep surface low and frontal boundaries
extending across the Mid Atlantic States. There is a good chance
for showers in the Mid Atlantic States by Sunday afternoon which
continue into Monday. Kept POPs no higher than 40 to 50 percent due
to a lack of confidence on days 6 and 7.
Max temperatures in the 50s Friday through Sunday warm to the lower
60s west of the Bay Monday. Lows in the mid 30s to lower 40s Friday
morning warm into the 40s Saturday through Monday mornings.
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
Challenging forecast as waves of showers preceed a warm front
this afternoon/evening given the prevailing BKN-OVC IFR CIGS.
Given the sporatic nature of the showers, decided to go with a
TEMPO group in the short term to account for the pcpn. CIGS will
vary from IFR to MVFR at times. Pcpn chances shift to the sern
and coastal areas after 00Z ahead of an approaching cold front
Wed morning. Models differences tonight make for a difficult
forecast as well. Despite increasing SW winds ahaed of the
front, data suggests widespread fog (possibly dense). Didn`t go
that low with VSBYS but did take them down to about 2SM with the
18Z issuance. Also wind shear is noted across coastal TAF sites
with a 40KT JET noted at 2K FT.
CIGS/VSBYS quickly improve after 12Z Wed with VFR conditions
expected along with gusty SW winds up to 20 KTS. Another low
pressure system looks to impact the region Friday, before dry
conditions return Saturday.
-- Changed Discussion --No headlines in the short term tngt thru Thu. Warm front will
lift well north of the area tngt, as a cold front pushes into
and acrs the waters Wed morning. Southwest winds 5 to 15 kt this
evening thru late tngt, will become west then northwest Wed
morning into early Wed aftn. Waves 1 to 2 ft and seas 2 to 3 ft.
High pressure will build into and over the waters for Wed night
thru Thu, with NW or N winds 5 to 15 kt. Waves 1 to 2 ft and
seas 2 to 4 ft.
The high slides into the Atlc late Thu night into Fri morning,
with a warm front lifting into and acrs the waters Fri into Fri
night. Winds will be SE or S 10 kt or less. A coastal low
pushes well out to sea on Sat, with weak high pressure building
in behind it during the day. Winds will be N then NE or E 10 kt
or less during Sat.
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