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fxus61 kakq 141143 
afdakq

Area forecast discussion
National Weather Service Wakefield Virginia
643 am EST Wed Nov 14 2018

Synopsis...
high pressure briefly builds over the northeast states today.
Another complex area of low pressure affects the region Thursday.
High pressure and dry conditions return Friday into the weekend.

&&

Near term /until 6 PM this evening/...
as of 645 am EST Wednesday...

High pressure quickly moves east across the nern states later
today and tonight. Still noting some lingering light rain along
the Albemarle Sound so kept slght chc pops there for few hours
as the latest high res data shunts all pcpn south of the fa by
15z. Otw, the high will provide enough dry air in the lower
levels to give the area a dry but cool day ahead of the next
system quickly taking shape across the south. Tsctns show mainly
high/mid level clouds so expect pt sunny skies north with mstly
cloudy skies south. Highs 45-50.

&&

Short term /6 PM this evening through Friday night/...
as of 345 am EST Wednesday...

The high quickly retreats to the NE tonight. Meanwhile, a deep upper
low moves east-northeast from the lower MS valley through the Tennessee Valley on Thu.
At the sfc, the fa will be wedged in between the strong retreating
high and sfc low pressure riding NE into the southern Appalachians
along with a secondary sfc low developing along the Carolina coast.
00z suite of data continues to show pcpn arriving across the south
during the evening then quickly spreading NE through the night.

An insitu-wedge scenario is shaping up with the likelyhood for some
mixed pcpn thurs morning across nwrn zones mainly northwest of Richmond.
The challenge as we see just about every year at akq is to what
extent any freezing rain falls vs a rain/sleet to rain scenario. The
latest models have come in just a tad warmer in the lower levels.
The latest BUFKIT sndgs suggests some freezing rain may mix in with
sleet across Fluvanna and wrn Louisa County with just a rain/sleet
mix to rain scenario from fvx-ofp. Sfc and wet bulb temps will be
hovering arnd 32/33 degrees so this will be a marginal event at best
with not much in the way of icing expected. Thus, after coord with
lwx and given the uncertainity, will hold off on any winter advsry
headline with this package and let the day shift further evaluate
sfc temps for later tonight. Otw, a cold rain overspreads the area
through the night. Lows ranging from the lwr 30s-lwr 40s. The other
issue will be temps across the lwr Maryland ern shore where temps after
sunset will likely drop to near 32 before rising after midnight
allowing the pcpn to be mainly liquid form. This area will have to
be watched for a brief mix at the onset but will keep it just rain
for now.

Next comes another batch of MDT to lclly heavy rainfall Thursday as
the models are showing decent lift ahead of the low. A widespread 1-
2 inch quantitative precipitation forecast event is likely thurs before a punch of drier air cuts
off the strong lift thurs night. Given that we just got a 1-2 inch
event yesterday, will go ahead and issue a Flood Watch fa wide given
the already saturated ground. Thinking is not one for flash flooding
but the typical flooding of low lying and poor drainage areas as
well as local rivers and streams which are already running higher
than normal. 100% pops with r+ at times. Expect a 25-30 degree temp
difference across the fa with temps nearly steady in the mid-upr 30s
northwest to between 60-65 alog the se cstl areas.

Pcpn assciated with the upr level system keeps the high pops thurs
evening with pops tapering off to some light rain/drizzle after
midnight as the system begins to pull north. Lows mid 30s northwest to mid
40s southeast.

The flow becomes a bit more zonal late in the week with high pres
building into the sern states. Dry, breezy and milder Fri with highs
ranging from the lower 50s northwest to around 60 f southeast. Clr Fri night with
lows from the upr 20s northwest to lwr 40s southeast.

&&

Long term /Saturday through Tuesday/...
as of 345 am EST Wednesday...

Relatively quiet wx with temps averaging a few degrees below
normal. Sfc hi pres will build into the region Sat then weaken
sun. A weak cold front will approach from the northwest late sun...then
cross the forecast area late Sun night-Mon. Will carry pops about 20% W/
the frontal passage...esp ern portions. Northwest flow aloft will bring
a return to dry but breezy/cooler wx by Tue as hi pres builds
towards the region.

Highs Sat in the l-m50s...except u50s far southeast. Lows Sat night in the
l-m30s west to the l40s at the coast. Highs sun in the l-m50s...except
u50s in southeast Virginia-NE NC. Lows Sun night in the M-u30s...W/ l-m40s
at the coast. Highs Mon in the l-m50s...except u50s in southeast Virginia-NE
NC. Highs Tue from the u40s north to the l50s S.

&&

Aviation /12z Wednesday through Sunday/...
as of 630 am EST Wednesday...

VFR conditions expected for most of the forecast period as high
pressure builds into the area from the northwest. Ceiling wise, expect sct
cumulus under a broken ac deck. Still noting some lingering light rain
ivof the Albemarle Sound so kept vcsh at ecg next few hrs as
the high res data shunts all pcpn south of the area by 15z.

Mid level moisture quickly returns this evening with some light
rain and lower clouds developing after 08z. North-NE winds become
gusty btwn 15-25 kts along the se coastal sites.

Outlook...
the next complex area of low pressure will impact the Thu/Thu
night, bringing a return to IFR/MVFR flight restrictions
(periods of moderate to heavy rain expected on thu). A rather
strong east/NE wind can also be expected near the coast Thu. Drier
air returns Fri but a gusty west/northwest wind will prevail. Dry Sat with
diminishing winds.

&&

Marine...
as of 345 am EST Wednesday...

Cold air surging into the region behind a departing cold front has
allowed for northwest winds to increase early this morning with winds
gusting 20 to 25 knots over a majority of the waters. Seas generally
range from 4 to 6 feet while waves range from 2 to 4 feet. Do expect
wind to die off slightly as we head into the late morning and
afternoon hours as high pressure briefly settles into the region.
Seas will likely remain at or above 5 feet and wind gusts will
remain borderline around 20 knots, so opted to leave the Small Craft
Advisory in effect through today.

A strong low pressure system approaches from the south later today
into Thursday. This system will move along the coast during the day
on Thursday before racing off to the northeast by Thursday night.
Winds quickly increase later in the day on Wednesday ahead of this
system and reach gale force by early Thursday morning. NE winds will
likely gust 35 to 40 knots through the day Thursday as the low
approaches the region. As a result, gale warnings are now in effect
for all waters minus the upper rivers Thursday morning through
Thursday evening. Seas will increase to 8 to 12 feet and waves 4 to
6 feet with higher waves at the mouth of the Bay. High surf
advisories and wind advisories might be needed at the immediate
coast during the day Thursday into Thursday night.

A brief lull in the winds is expected late Thursday as the low moves
along the coast. Winds turn to the northwest Thursday night into Friday
morning and potentially gust to gale force once again over the
coastal waters. Winds will remain in the 20 to 30 knot range into
Friday afternoon. Winds and seas will remain stirred up into
Saturday morning, likely requiring additional Small Craft Advisory headlines. Calmer
conditions return for the weekend as high pressure settles over the
region.

&&

Hydrology...
as of 645 am EST Wednesday...

River flood warnings remain in effect for Stony Creek on the
Nottoway, Farmville and Mattoax on the Appomattox, Lawrenceville
on the Meherrin and Sebrell on the Nottoway. Expect additional
rises and possible warnings on local rivers given the expected
rainfall Thursday.

&&

Akq watches/warnings/advisories...
Maryland...Flood Watch from Thursday morning through Thursday evening for
mdz021>025.
NC...Flood Watch from Thursday morning through Thursday evening for
ncz012>017-030>032-102.
Virginia...Flood Watch from Thursday morning through Thursday evening for
vaz048-060>062-064>069-075>090-092-093-095>100-509>525.
Marine...Small Craft Advisory until 7 am EST Thursday for anz630-631-
638-650-652-654.
Gale Warning from 7 am to 10 PM EST Thursday for anz650-652-
654.
Small Craft Advisory until 4 am EST Thursday for anz632>634-
656-658.
Gale Warning from 4 am to 7 PM EST Thursday for anz632>634-656-
658.
Small Craft Advisory from 4 am to 7 PM EST Thursday for
anz635>637.
Gale Warning from 7 am to 7 PM EST Thursday for anz630-631.
Gale Warning from 7 am to 4 PM EST Thursday for anz638.

&&

$$
Synopsis...mpr
near term...mpr
short term...mpr

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