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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 181912
AFDRNK

Area Forecast Discussion
National Weather Service Blacksburg VA
312 PM EDT Wed Apr 18 2018

.SYNOPSIS...
Low pressure will move through the middle Atlantic region and
push a cold front through the Appalachians and central mid
Atlantic region. This will bring very windy conditions, along
with much colder temperatures, along with some showers west of
the Blue Ridge and even some west snow for the higher
elevations. High pressure then builds in with fair conditions
and slightly warmer temperatures into the weekend.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 225 PM EDT Wednesday...

Low pressure will move through the middle Atlantic region and
push a cold front through the Appalachians and central mid
Atlantic region. This will bring an abrupt end to our one day
of spring as much colder air moves in on strong gusty northwest
winds. Expect rain showers with the front west of the Blue Ridge
to transition to upslope rain/snow showers on Thursday with
some minor snow accumulation for the higher elevations. The
upslope precipitation will be decreasing during Thursday
afternoon.

The winds behind the front will become quite strong as cold air
advection creates efficient downward momentum transfer with
gusts around 50MPH at the higher elevations from the Blue Ridge
westward starting around Midnight and continuing through
tomorrow. Gusts will not be quite as strong east of the Ridge
and will generally wait for the arrival of netter mixing with
diurnal heating by mid/late morning.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
As of 300 PM EDT Wednesday...

Models agree on continuation of stronger winds at least until
midnight Thursday night, especially along the Blue Ridge as 45 kt
jet shifts toward the southern Shenandoah Valley.

Expect some linger flurries in western Greenbrier, then dry, sunny
and cool Friday. May have some freeze issues late Thursday night but
no frost as RH only recovers to 60-65 percent and winds will be
blowing.

Highs Friday will be in the 50s in the mountains, with even some 40s
in the higher ridges of the Alleghanys, to lower to mid 60s across
the foothills/piedmont.

May have more of a freeze/frost issue late Friday night, especially
in the southern Shenandoah Valley as winds drop off and temps drop
to near freezing. No headlines at this point.

Saturday, the surface high continues to build in from the Great
Lakes providing sunshine and warmer highs in the 60s.

Clouds increase ahead of the upper system moves into the lower MS
valley.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
As of 145 PM EDT Wednesday...

Going to be wet/cool but not cold period, as upper low develops over
the lower MS Valley Sunday and pushes across the northern tier of
the Gulf Coast states Sunday afternoon into Tuesday. Models have
trended north, but would like to see more consistency in them, as a
further south track would lead to dry/cool with more sun while north
would be wetter/cloudier but still a bit on the cool side.

For consensus, models are showing more of cloudy pattern with threat
of rain each day. As the low moves off the coast Wednesday, a
northern stream front shift in from the northwest with another
threat of showers.

Sunday appears the drier of this period with increasing clouds.
Highs will range from the mid 50s to lower 60s mountains, with mid
to upper 60s in the piedmont/foothills, which is about 5 degrees
below normal.

Lows will be close to normal during the week with mid 30s to lower
40s west, to lower to mid 40s east.

Highs Monday-Tuesday will be around 10 degrees below normal, ranging
from the lower to mid 50s west, to upper 50s to lower 60s east.

May be a little warmer Wednesday ahead of next front with upper 50s
to lower 60s mountains, to mid to upper 60s east.
-- End Changed Discussion --

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
As of 215 PM EDT Wednesday...

Low pressure will move through the middle Atlantic region and
push a cold front through the Appalachians and central mid
Atlantic region. So after VFR conditions to start off the
period, locations west of the Blue Ridge will trend to generally
MVFR, possibly IFR, as the front brings upslope showers to the
region. Colder air moving in will gradually mix/change to snow
showers. Don`t expect much spill over past the Ridge so will
maintain a VFR forecast in the east.

Conditions will become quite windy behind the front as cold air
moves in and makes for efficient momentum transfer of vigorous
low level winds to the surface. Expect the strong gusts to make
their way east of the Blue Ridge primarily with onset of heating
and better diurnal mixing. Gusts AOA 40kts can be expected
along/west of the Blue Ridge, around 30kt to the east.

Extended Aviation Discussion...

VFR returns Friday although gusty north winds to persist as
high pressure slowly builds in from the northwest. Winds should
diminish by Saturday with VFR ceilings and visibilities.

Clouds will begin to creep back into the area on Sunday in
advance of an approaching low in the Lower Mississippi River
Valley. However, cigs should remain VFR while the ceiling heights
lower and clouds thicken. SCT MVFR showers are possible in
southern Virginia and northern North Carolina Sunday night into
Monday morning.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
VA...Wind Advisory from 10 PM this evening to 6 AM EDT Friday for
     VAZ007-009>020-022>024.
NC...Wind Advisory from 10 PM this evening to 6 AM EDT Friday for
     NCZ001-002-018.
WV...Wind Advisory from 10 PM this evening to 6 AM EDT Friday for
     WVZ042>044-507-508.
-- End Changed Discussion --

&&

$$
SYNOPSIS...MBS
NEAR TERM...MBS
SHORT TERM...WP
LONG TERM...WP
AVIATION...AMS/KK