Area Forecast Discussion
Issued by NWS Wakefield, VA-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KAKQ 191443
Area Forecast Discussion
National Weather Service Wakefield VA
943 AM EST Sun Feb 19 2017
High pressure builds into the area today. A backdoor cold front
pushes south across the area tonight. High pressure builds well
north of the region and slides off the coast by Tuesday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --Current wv imagery shows an upper trough pushing off the
Carolina coast, with a lingering trough axis sliding across the
Delmarva producing some mid/high (AC/CI) clouds. The surface
pressure pattern is weak and generally characterized by a weak
trough over the Ern Conus, and high pressure over the Tennessee
Valley. Cross-sections indicate the skn-bkn clouds with the
trough will thin through the day. 850mb temperatures drop to
around 6-8C, but will be offset by downsloping light NW flow.
Above normal temperatures continue (+1.5 - 2.0 st dev) with
highs in the lower 70s except mid to upr 60s along the coast.
Readings may hover around 60 at the beaches. Record highs appear
safe but may be approached at SBY. See CLI section below.
-- End Changed Discussion --
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
High pressure over eastern Canada pushes a backdoor cold front south
across the are this evening. The 1030+ mb high continues to build
ewd Monday resulting in onshore flow and cooler conditions near
the water while the Piedmont stays mild. Lows tonight in the 40s.
Highs Monday range from the low/mid 50s for the Ern Shore, low
to mid 60s in the I-95 corridor, to the low 70s over the Piedmont.
High pressure prevails over the region Monday night. Colder with
lows dropping into the low/mid 30s NE to the upper 30s/around 40
W under a mostly clear sky.
The high slides offshore Tuesday as a weakening cold front approaches
from the W. Mixing will be limited, only to about 950-925mb, with
high temperatures ranging from the low/mid 50s NE to the lwr 60s
SW. Dry with increasing clouds by aftn.
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
High pressure slides off the Mid Atlantic Coast Tue night and
settles over the Southeast coastal waters on Wed. The area
continues to sit in the middle of split flow aloft (primarily
westerly flow) with active systems passing well north and well
south. Models still struggling in regard to how far south to
bring precip associated with nrn system. However, available
shortwave moisture/energy is still being sheared apart. Have
maintained ongoing precip forecast by keeping a slight chance
for showers mainly across nwrn half of CWA during Tue night with
dry conditions for Wed as aforementioned shortwave moves
offshore. Otherwise, expect a dry forecast through Thu night
with temperatures running anywhere from 15-20 degrees above
seasonal normals. Lows generally mid 40s to mid 50s. Highs
generally mid-upper 60s to lower 70s inland/low-mid 60s
immediate coast. Next big system to potentially impact the Mid
Atlantic Region exits the Plains Thu night and tracks northeast
into the Great Lakes on Fri. Increasing south winds and decent
warming ahead of a strong cold front is anticipated for Fri/Fri
night. Scattered showers will be possible Fri aftn/evening and
maybe even some thunder...but only if the timing of the frontal
passage doesn`t change (i.e. the arrival of the front will
likely slow down its ewd progression as upper level troughing
digs behind the sfc low). Forecast highs for Fri are currently
in the low-mid 70s inland/low-mid 60s beaches, however they
could easily end up being several degrees warmer due to a
tightening pressure gradient and subsequent well-mixed
environment, ample warm air advection occurring ahead of the
front, and longer daytime hours as we approach meteorological
spring. Lows Fri night will be highly dependent on when the
frontal passage occurs. Warm temps should be anticipated through
most of the night with readings falling in the Piedmont and far
nw counties closer to sunrise. For now, lows Fri night will be
around 50F (+/- a few degrees).
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
SCT to BKN AC/CI thins out as the day wears on due to high
pressure building in from the west. A dry cold front moves south
across the area later today shifting the winds into the NNW at
less than 10 KTS. SKC expected after 00Z.
OUTLOOK...Sct shwrs possible Tuesday night. Otw, dry wx through
Sub-SCA conditions through at least mid week. A trough of low pres
slides through the area this morng as low pres develops off the SE
cst, with 10-15 kt SW winds shifting to the NW by later this morng.
Waves over the Bay 1-2 ft with seas over cstl wtrs 2-3 ft. Similar
conditions into tonight with a slight uptick in winds (up to ~15 kt)
as a weak cold front drops through the area. High pres then builds
in from the west Mon, settling over the wtrs Mon night into Tue
allowing for benign marine conditions to continue.
Record highs for today:
* Site 2/19 Forecast highs
* RIC: 78 (1961) 73
* ORF: 73 (1907) 68
* SBY: 72 (1961) 71
* ECG: 77 (1939) 69