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-- Discussion containing changed information from previous version are highlighted. --
115
FXUS61 KAKQ 181540
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1040 AM EST Sat Jan 18 2020

.SYNOPSIS...
Strong high pressure centered to the north, will slide offshore
this afternoon. A weak warm warm front will lift across the
area today, with a cold front will push across the region late
tonight into Sunday morning. Cold high pressure builds back in
for Sunday afternoon through Wednesday, with markedly colder air
spilling across the region through the middle of the week ahead.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1040 AM EST Saturday...

Forecast largely on track, with only minor changes made to
reflect conditions/radar trends. Some very light overrunning
moisture bringing some light snow/sleet to far NW portion of the
area (*Fluvanna/Louisa Counties) this morning. With some MPing
reports of some light rain across the I-95 corridor north of RIC
over to the eastern shore late this morning. Noted some light
snow over the northern neck/eastern shore earlier this morning,
which have tapered off with the initial slug of light pcpn now
offshore.

Nudged PoPs back in time a few hours, with llvl dry slot looking
to keep a lid on rain chances into the mid-late aftn inland, and
into this evening over Hampton Roads. Likely to categorical PoPs
in place after 5pm this aftn, continuing into the late night
hours before tapering off late. Becoming breezy tonight ahead of
the approaching cold front, which crosses the area late tonight.

Previous discussion follows...

       As of 630 AM EST Saturday...

Quick update to PoP and weather grids to capture areas of light
snow and snow flurries translating eastward from the Northern
Neck and eventually into the MD eastern shore this morning.
Degree of lift has been just enough to overcome dry low levels
and result in a brief period of light snow/flurries at the
surface. Issued an SPS to cover this threat and any impacts to
travel should be minimal. The remainder of the forecast is on
track.


            Previous Discussion as of 345 AM EST Saturday...

Strong high pressure, centered near/north of New England, will
continue ridging southward this morning before moving offshore
this afternoon. Meanwhile, low pressure over the Midwest moves
eastward with a trailing cold front approaching the region from
the west by this evening. A weak warm front moves northward this
morning with model guidance showing some concentrated lift/WAA
skirting the northern third of the region this morning. With
very dry air in place at the surface, not expecting much if any
precip at the ground but a brief flurry is possible across the
north (~Louisa-NE to Dorchester county, MD) if precip intensity
aloft is sufficient. Otherwise, mostly dry through early
afternoon as trend in guidance to delay onset of significant
precip continues. Temps will likely be too warm by this
afternoon to support any P-type issues but dry air at the
surface will allow evaporational cooling to decrease temps a few
degrees across the NW as precip falls and in-situ wedging sets
up. Southeasterly flow elsewhere across the region will allow
temps to warm into the mid 40s to low 50s. Rain spreads eastward
this afternoon and to the southeast by this evening before
moving offshore overnight. South and southwest winds increase
and become gusty this afternoon into the overnight as the
pressure gradient tightens ahead of the cold front, which is now
forecast to cross the region Sunday morning. Lows tonight range
from the mid 30s NW to right around 50 degrees SE.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 345 AM EST Saturday...

Precip moves offshore before sunrise on Sunday with westerly winds
in the wake of the cold frontal passage. Winds become gusty again on
Sunday as skies begin to clear and deep mixing gets underway by mid
morning. Westerly/downsloping flow will keep temps from falling too
far behind the front with highs in the mid 40s to mid 50s. Strong
Canadian high pressure and associated CAA build in on NW winds for
Sunday night with low temps ranging from the low 20s NW to low 30s
SE.

Noticeably colder on Monday with temperatures in the mid 30s across
the north and even struggling to breach the 40 degree mark across SE
VA and NE NC. Strong NW winds will gust 15-20mph inland and 20-25mph
near the coast/eastern shore, resulting in wind chills in the upper
20s and low 30s for much of the area. Winds decrease inland by
evening but remain elevated over the water through the overnight.
Very cold Monday night with temps ranging from the upper teens
across the Piedmont to mid 20s over the SE.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 355 PM EST Friday...

For much of next week, high pressure will be in control at the
surface and troughing aloft. While mainly dry/sunny conditions are
expected, next week will feature much colder air compared to the
past few weeks. Highs on Tuesday and Wednesday will struggle to
climb out of the upper 30s and lower 40s across the region, with
overnight lows Monday night through Wednesday night ranging from the
teens to low 20s inland to the mid to upper 20s at the coast. A
gradual warming trend begins Thursday into Friday as the center of
high pressure begins to shift eastward and ridging develops across
the Eastern US. An area of low pressure potentially develops across
the central Thursday before moving northeast during the day on
Friday. This area of low pressure and its associated frontal
boundary may bring a chance of rain to the area late Friday into
Saturday.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
As of 630 AM EST Saturday...

VFR conditions with high pressure over the region, which moves
offshore this late this morning as low pressure and a cold
front approach the region from the west. Light and variable E/NE
winds will become SE/S through the morning hours and S/SW and
gusty by the afternoon as the gradient tightens. BKN/OVC high
clouds over the region will gradually lower into the afternoon
as rain spreads from west to east 18-00Z. CIGs lower to MVFR
late afternoon/early evening at RIC and SBY, a few hours later
at PHF, ORF, and ECG. Some guidance is showing potential for IFR
CIGs at SBY and RIC after 00Z but held off on explicit mention
in the forecast.

OUTLOOK...Cold front crosses the area on Sat night into Sun
morning, with any lingering pcpn ending from NW to SE. High
pressure builds back in for Sun and Mon.

&&

.MARINE...
As of 345 AM EST Saturday...

1040mb high pressure is centered over the Adirondack region
of NY early this morning, and the high extends swd into the Mid-
Atlantic region. The wind is generally ENE 5-10kt, with seas of 3-
4ft for most of the coastal Atlantic, and 4-5ft off the Currituck
Outer Banks. Therefore, the SCA will be allowed to expire from the
VA/NC border to Cape Charles, and it has been extended through 7 am
off the Currituck Outer Banks. The strong high will push offshore
today into tonight as low pressure tracks across the Great Lakes
today and across New England Sunday. This will produce strong
pressure falls (5-6mb/3hr) and the wind will become S 15-25kt later
this aftn, then SW 15-25kt tonight. Seas return to 3-5ft S tonight,
and build to 4-6ft N, with 2-4ft waves in the Bay. The wind will
then become WNW 12-20kt Sunday. SCA flags have been issued for the
middle Bay beginning 1 pm today, srn Bay, lower James 4 pm, and nrn
ocean (N of Cape Charles) 4 pm today, and then the Currituck Sound
and srn ocean 7 pm today. SCAs gradually end Sunday morning, with
the exception of the nrn ocean where seas could linger ~5ft out
toward 20nm.

A cold front crosses the coast Sunday night with the wind becoming
NW 15-25kt into Monday morning, before diminishing to 15-18kt midday
into the aftn. A secondary surge of CAA arrives Monday night into
early Tuesday morning with a 15-20kt NNW wind. High pressure builds
into the region Tuesday into Wednesday. The wind will gradually veer
from NNW to NNE with speeds ~15kt N to 15-20kt S. Seas are expected
to average 4-5ft Monday-Tuesday, and could build to 6ft S as the
wind becomes more northerly. Waves in the Bay are forecast to reach
3-4ft Sunday night and Monday night during the periods of strongest
CAA.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory from 4 PM this afternoon to 10 AM EST
     Sunday for ANZ632-634.
     Small Craft Advisory from 7 PM this evening to 7 AM EST Sunday
     for ANZ633-656-658.
     Small Craft Advisory until 10 AM EST Sunday for ANZ630-631.
     Small Craft Advisory from 4 PM this afternoon to 4 AM EST
     Sunday for ANZ638.
     Small Craft Advisory from 4 PM this afternoon to 7 PM EST
     Sunday for ANZ650-652-654.

&&

$$
SYNOPSIS...RHR
NEAR TERM...MAM/RHR
SHORT TERM...RHR
LONG TERM...AJB
AVIATION...RHR
MARINE...AJZ/ERI