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000
FXUS61 KAKQ 250035
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
835 PM EDT Sat Oct 24 2020

.SYNOPSIS...
A cold front crosses the area tonight. Canadian high pressure
wedges down over the area behind the front with much cooler
weather for Sunday. Another front will move into the area later
Tuesday through Wednesday.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 810 PM EDT Saturday...

Latest sfc analysis shows the cold front is dropping SSE
through the local area and is located invof the VA/MD border
over the Eastern Shore and extends SW/WSW to the I-85 corridor.
Other than an isolated thunderstorm in Mecklenburg, scattered
showers along and behind the front will increase in coverage
overnight with the highest PoPs in the piedmont.

QPF amounts through this evening generally under a quarter inch
from I-95 west, and lesser amounts as you head east towards the
coast with the exception of a few locally heavier showers
in the Middle Peninsula and Peninsula.

After the cold front moves through, high pressure will begin to
nudge back into the area from the north tonight, setting the
stage for an overrunning CAD wedge setup, with likely light rain
and drizzle late tonight and through much of tomorrow. Will
transition ptype to stratiform rain after midnight with most
areas seeing at least some light rain along with overcast
conditions. Lows from the upr 40s NW to the low 60s SW.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
As of 340 PM EDT Saturday...

High pressure will expand over the area on Sunday, helping to
reinforce the CAD setup east of the mountains. Expect a mostly
cloudy to overcast sky with some light rain and drizzle
throughout the day over the piedmont. Temps will likely be
their highest over the NW just after midnight late tonight/early
Sunday, remaining steady or falling slowly through the morning.
Meanwhile, SE portions of the area will see a little bit of a
temp rebound during the day but still remaining cool. QPF has
been kicked up slightly, as a southern stream shortwave moves
across the SE coastal plain later Sun morning through Sunday
aftn. This will result in more widespread rain across the
central and eastern portions of the area, which exits the area
from SW to NE Sunday evening. Overcast, cool, and raw,
especially inland, with daytime highs Sunday in the upper 40s
NW, upper 60s to low 70s over NE NC. lingering light rain and
drizzle Sunday night, with lows to range from the mid 40s NW to
around 60 SE.

Drier conditions on Monday as the high to our north shifts to the
east over the Canadian Maritimes, with another surface high building
in over the local area. The flow will become southerly, albeit
light, by Monday afternoon. This will allow the cool air wedge to
break down gradually with a decent rebound in temps expected.
Still did nudge cloud cover up and temps down far inland
sections in anticipation of Wedge hanging on Mon morning before
starting to break down late. High temps in the low-mid 60s
inland, upper 60s to low 70s central, mid 70s NE NC.

Sfc high lingers along/just offshore Tuesday, as a weakening
front slowly drops across the northern mid-Atlantic toward the
local area. Remaining dry and turning a bit milder, as any CAA
holds off until later Tuesday night/Wed. Highs in the upper 60s
to mid 70s inland, mid 70s to around 80 SE.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 300 PM EDT Friday...

Forecast period begins with previously referenced (weak) cold
front dropping across the area later Tuesday into Tue night.
Weakening forcing should ensure a mainly dry night Tuesday
night, into the day on Wednesday, though slight chance PoP has
been retained for a few stray showers Wed+. Model guidance
still intent on developing an upper low over the desert
southwest, eventually evolving into a cutoff low by the middle
of next week.

Considerable model differences remain, with the GFS still on the
more progressive side of the guidance envelope, showing the
system getting picked up and absorbed into the east coast mean
trough. The 12z/24 CMC/12z ECMWF, like their respective
ensemble means are a bit slower and more amplified. Have stayed
away from the very high PoPs on the NBM for now given this
uncertainty. Nevertheless do nudge rain chances up into high end
chance range Wed night/Thursday morning with at least slight
chance PoPs persisting through the remainder of the long term
forecast period. Have capped PoPs in the 40-50% for the time
being until a more solid model consensus is attainable.

For temps, expect a slight cool down behind the front Wednesday
and Thursday, with highs generally ranging from the mid 60s
north to the low to mid 70s south. Early morning lows through
the period generally range through the 50s to around far 60 SE.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
As of 830 PM EDT Saturday...

VFR conditions over all terminals continue through around
05-06z Sunday when MVFR ceilings around 3000 ft move into RIC
and the piedmont. All terminals will see diminishing flight
conditions through the day with ceilings lowering to MVFR
between 06z to 10z Sunday and to IFR after 15z. From 18z through
the remainder of the 00z taf, all terminals will be IFR.
Visibilities will also begin to decrease through the afternoon
to around 3-4 SM by around 18z. Recent models have trended even
lower with visibilities, possibly to 2 SM or less at times
after 18z.

Light rain and drizzle will be possible through the day with a
wedge setup in place. Fog will also be possible during Sunday
evening as well. Winds will shift from SSW/SW 5 to 10 kt at
ORF/PHF/ECG to NNE over the next few hours as the cold front
drops south. A brief period of gustier winds (8-12 kt with gusts
15 to 20 kt) will be possible from 06 to 12z as the colder air
advects into the region.

Outlook...Wedge pattern with low ceilings and possibly low
visibilities as well due to fog will remain in place through
Sunday night with flight restrictions likely. Conditions should
improve/dry out for Monday, although low clouds/fog may be an
issue early on.

&&

.MARINE...
As of 340 PM EDT Saturday...

Late this afternoon, Hurricane Epsilon is well offshore of the
Northeast US coast and tracking away from the area, while a cold
front is just to the NW of the local waters. Winds are generally W-
SW at 5-10kt (with some areas seeing a sea breeze component to the
wind). Seas remain elevated due to swell from Hurricane Epsilon, and
are averaging around 5ft. Waves on the bay are ~1ft in most areas,
with 2-3ft waves at the mouth of the Bay. The cold front is progged
to cross the waters from N to S during the evening-early Sun AM
before stalling near or just south of the NE NC coastal waters by
12z Sun. Winds will shift to the N then NE and will increase to
around 20kt on the ocean N of the VA-NC border, Ches Bay, and Lower
James River tonight into Sunday morning. Still expecting winds to be
just below SCA criteria on the upper rivers and Currituck Sound,
although a few gusts to 20kt are possible. On Sunday, a weak trough
of low pressure establishes itself just offshore of the NC coast
before moving NNE late Sunday into Sunday night as high pressure
builds over central portions of VA/NC. Winds will likely average 15-
20kt over the Ches Bay and coastal waters N of Cape Henry through
much of the day on Sun, with ~15kt winds across the Currituck
Sound/far srn coastal waters. Winds diminish to 10-15kt and turn
more to the NNW by Sun night/early Mon AM as the trough of low
pressure slowly pulls away from the waters. Seas build to 5-7ft
across most areas, with waves of 2-5ft on the Ches Bay (highest at
the mouth). SCAs remain in effect through Sun night-early Mon AM for
the ocean and mouth of the Ches Bay. Went ahead and extended SCAs
through 1 PM Sunday for the remainder of the bay/Lower James River.
It is possible that SCAs for the bay/Lower James may need to be
extended into early Sun evening, but will let the next shift assess
the latest trends. Still not enough confidence to issue an SCA for
the Currituck Sound (frequent 20kt gusts likely stay just N of the
sound), although one may be needed if the front stalls a bit further
south than currently forecast.

Weak high pressure settles across the area Monday and moves offshore
by Monday night. Another weak cold front/CAA surge potentially
arrives on Tuesday or Tuesday night. There is still some
disagreement with the models with respect to timing, but the current
forecast has conditions remaining a bit below SCA thresholds from
Tue-Wed AM. An area of low pressure and a stronger cold front is
progged to affect the marine area late this week. Another round of
SCAs is likely sometime during the Thu-Sat timeframe.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 1 AM EDT Monday for ANZ634.
     Small Craft Advisory until 1 PM EDT Sunday for ANZ630>632-638.
     Small Craft Advisory until 6 AM EDT Monday for ANZ650-652-654-
     656-658.

&&

$$
SYNOPSIS...MAM
NEAR TERM...MAM/RMM
SHORT TERM...JDM/MAM
LONG TERM...AJB/MAM
AVIATION...RMM
MARINE...AJZ