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Area forecast discussion
National Weather Service Wakefield Virginia
336 PM EST Tue Nov 12 2019

cold front has cleared the area with trailing rain and snow
ending early this evening. High pressure and much below average
temperatures build in from the west through midweek. This area
of high pressure moves offshore later in the week as low
pressure tracks northeast off the Carolina coast.


Near term /until 6 am Wednesday morning/...
as of 300 PM EST Tuesday...

Snowfall rates this afternoon were quite impressive over the
Richmond Metro, allowing a quick dusting to half inch accumulate on
non Road surfaces in a short period of time. Most areas will see a
rain/snow mix as the precip races east however on the back end of
the precip shield there will likely be a window of all snow. Most
areas will see little to no accumulation, however a quick dusting to
half inch of snow is possible in areas where rates can over come the
warm ground temps. Behind the precip shield, temps will likely raise
back up a couple degrees before continuing to fall later this
evening. Gusty north/northwest winds this afternoon and tonight 20-30 mph, with
higher gusts. Winds will be a bit stronger across the se, a short
term Wind Advisory is in effect until the early part of the evening
for Virginia Beach and NE NC where winds may gust to around 40 mph.
Temps will plummet throughout the evening dropping into the 20s by
late tonight out west and the 30s out east. With the rain/snow
creating wet surfaces today, there is some concern about potential
flash freezing late tonight into the morning hours tomorrow. The
gusty winds tonight should help dry out most Road surfaces, however
some black ice on secondary roads is possible.

Bulk of the rain/snow will be out of the area after 00z, but an
interesting feature will set up overnight into Wednesday morning.
All of the high res models are picking up on a north/S streamer over
Hampton Roads as cold air moves over the much warmer waters of the
Bay. At the very least, this will result in holding cloud cover into
the Hampton Roads area. However, if there is enough sufficient
moisture in the low levels, would not be surprised to see some
flurries/snow showers out of this band. Forecast models over the
area show some shallow moisture will be available, and surface to
850mb temps will be about 13-16c. For the moment, have not added any
snowfall amounts to the grids, but flurries to a slight dusting in a
narrow corridor south of the Bay is not out of the question.

Temps Wednesday morning will be much below normal. Expect upper
teens to lower 20s north and west of Richmond, and mid to upper 20s
across Southside and NE NC. Freeze watch has been upgraded to a
warning through 9 am EST Wednesday and that will likely end the
frost/freeze program until the Spring.


Short term /6 am Wednesday morning through Friday/...
as of 300 PM EST Tuesday...

Cold high pressure builds in for Wednesday and Thursday. High
temps on Wednesday will likely remain in the 30s for most.
Thursday morning will be just as cold if not a couple degrees
colder than Wednesday morning as the surface high will be
centered right over the forecast area. High temps on Thursday
moderate closer to normal with upper 40s northwest to near 60 southeast.

Friday a low pressure system is expected to develop off the southeast
coast. Rain showers well north of the center may impact southeast portions
of the forecast area on Friday, for now have just chance pops over
the southeast portions of the forecast area. High temps on Friday will be
in the 50s and near 60 close to the coast.


Long term /Friday night through Tuesday/...
as of 300 PM EST Tuesday...

Both the GFS and European model (ecmwf) have an area of low pressure developing off
the southeast coast late Friday through Saturday. This area of low
pressure then lifts to the north-northeast on Sunday and Monday, but
remains well offshore. Rain showers develop across the southeast Saturday
afternoon, and spread north through the day Sunday as the low lifts
further to the north. Areas to the west of I-95 should remain
mainly dry during this timeframe, though cloud cover will be on the
increase. East of I-95, there will be a slight chance to chance of
rain (increasing in coverage further S and e) Saturday afternoon
through Sunday. Rain may briefly try to mix with some wintry
precipitation on the far western portions of the precipitation
shield Saturday night where cooler air will remain in place, but for
now confidence is too low to include this in the forecast.
Rain chances increase area-wide Sunday night through Monday as the
area of low pressure lifts north of the region. Unsettled conditions
continue Tuesday, especially near the coast, as another area of low
pressure develops off the southeast coast. Temperatures remain below normal
through the forecast period.


Aviation /21z Tuesday through Sunday/...
as of 1230 PM EST Tuesday...

Cold front is just about through the forecast area this
afternoon. IFR/MVFR cigs/vsbys this afternoon until the
rain/snow ends later today. Winds behind the front will be north/northwest
and gusty. Expect 10-20kts with higher gusts. Winds at korf will
gust 30-35kts at times this afternoon and early evening.
Cigs/vsbys improve dramatically after 00z tonight, however winds
will remain elevated through Wednesday morning.

VFR conditions return Wednesday into Thursday. Low pressure
pushes off the southeast coast Friday/Saturday bringing the
potential for rain and degraded flight conditions.


as of 335 PM EST Tuesday...

Latest obs reflect Post-frontal north-northwest flow 20 to 25 knots with gusts
to 30 knots for the eastern Virginia rivers and most of the Chesapeake
Bay this aftn. A few elevated sites are reporting low end gale force
gusts in the middle ches Bay, but predominate winds are sub-Small Craft Advisory and
for that reason will keep headlines as is for now.

After a brief lull this evening where winds level off to high-end
sca, 850 mb front will cross the region tonight, bringing strongest cold air advection
surge after 00z/7pm tonight through early Wednesday morning. Speeds
will reach 25 to 30 knots with gusts between 35 and 40 kt for the
mouth of the Chesapeake Bay, the Currituck Sound and all of the
local coastal waters during this time frame late tonight
and overnight, with scas will remain in effect for the remainder of
the local waters. Waves will reach 3-5 feet on the ches Bay tonight
with seas building to 5 to 9 feet by tonight (highest south). A high
surf advisory remains in effect from Virginia Beach southward from 7 PM
this evening through early Wednesday afternoon with breaking waves
of 6 to 9 feet expected.

High pressure builds in rather quickly by Wednesday afternoon with
improving conditions. A period of scas will be needed for areas
currently under a Gale Warning once they expire (from later Wed
morning into the afternoon as winds/seas diminish/subside). High
pressure moves offshore Thursday. The end off the week into the
weekend looks to be unsettled as low pressure nearshore and high
pressure over the northeast lead to an extended period of enhanced
northeasterly flow over the region. In fact, a coastal system is
likely to bring another round of gale conditions to the local waters
Friday night through Sunday morning.


a strong cold front will cross the region today, with the
coldest air of the season spreading across the area tonight
through Thursday. Record low and low Max temperatures for
Wednesday 11/13 are below:

location low (11/13) year
------- -------- ------
Richmond 20 1941
Norfolk 27 1934
Salisbury 19 2001

low Max
location (11/13) year
-------- ------ ----
Richmond 37 1911
Norfolk 42 1920
Salisbury 42 1977


Akq watches/warnings/advisories...
NC...freeze warning from 2 am to 9 am EST Wednesday for ncz017-102.
Wind Advisory until 6 am EST Wednesday for ncz102.
High surf advisory from 7 PM this evening to 1 PM EST
Wednesday for ncz102.
Virginia...freeze warning from 2 am to 9 am EST Wednesday for vaz095-098-
Wind Advisory until 6 am EST Wednesday for vaz098.
High surf advisory from 7 PM this evening to 1 PM EST
Wednesday for vaz098.
Marine...Small Craft Advisory until 4 am EST Wednesday for anz635>637.
Gale Warning until 7 am EST Wednesday for anz633-634-650-652-
Small Craft Advisory until 10 am EST Wednesday for anz630>632.
Small Craft Advisory until 7 am EST Wednesday for anz638.


near term...cmf
short term...cmf

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