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fxus61 krnk 181145 

Area forecast discussion
National Weather Service Blacksburg Virginia
745 am EDT Wed Oct 18 2017

high pressure will remain over the area through the weekend. A
deepening upper-level trough and cold front will approach the
region from the west early next week. Rain is not expected
before early next week while temperatures will trend a bit
warmer into the weekend.


Near term /through tonight/...
as of 330 am EDT Wednesday...

Dry, high pressure will remain over the area through the period.
The center of the large high pressure area will drift slightly
eastward through the period and will be aligned near the Blue
Ridge by Thursday morning. Other than a few passing cirrus from
time-to-time, expect mostly clear skies. Starting out this
morning a few degrees warmer than Tuesday morning and 850mb
temps will warm into the +10c to +12c range by late today. This
should allow maximum temperatures to be on the order of 5-6
degrees warmer than they were Tuesday. By the same token morning
low temperatures Thursday will also be a few degrees warmer as
well. Burkes Garden and Lewisburg should be among the few spots
able to make it to or below the freezing mark Thursday morning.
Frost should be less widespread as well and generally only
patchy frost is indicated in the grids at this time with no


Short term /Thursday through Saturday night/...
as of 330 am EDT Wednesday...

High pressure will be centered over the mid-Atlantic region through
Friday. There is a weak dry front that will pass north of the area
Thursday, but hardly Worth mentioning aside from a subtle wind
shift. The dominant feature will continue to be the dome of high
pressure and its persistence, with strong subsidence and dry air
resulting in large nocturnal/diurnal temperature swings. High
temperatures will favor the warmer side of normal by +4 to +8
degrees, with highs in the 70s. Lows will be close to the seasonal
norm with readings in the lower to mid 40s.


Long term /Sunday through Tuesday/...
as of 330 am EDT Wednesday...

Amplified upper ridge over the southeast will continue dry and warm
weather heading into the weekend. Saturday night into Sunday, the
ridge axis begins to move east as the trough deepens into the middle
of the country. The trough axis will move into the Ohio Valley
Monday and rotate eastward into Tuesday. The trough axis should be
located along the coast by Wednesday. The GFS and European model (ecmwf) continue to
disagree on the depth and strength of trough and where to close off
a southern low. Despite the fact that the location is different,
both solutions show a low closing off, upper flow turning more
southwest, and an influx of moisture. This should result in an
increasing chance of showers early next week.

Temperatures staying above normal through Sunday, then a cooling
trend expected Monday into Wednesday.


Aviation /12z Wednesday through Sunday/...
as of 745 am EDT Wednesday...

A large, very dry high pressure area will remain over the region
through the valid period drifting ever so slowly east by
Thursday. GOES-16 clearly shows River Valley fog west of the
Blue Ridge, but as far as the asoss/taf sites are concerned,
bcb is the only one actually reporting restrictions to
visibility. At any rate, this fog will dissipate quickly by 13z
leaving just few- sct250 through the day. MVFR to IFR fog will
again be possible early Thursday, and perhaps lyh may see some
then as well. Otherwise, not expecting any restrictions to
ceilings or visibilities through the period with mostly sky clear.

Winds will be mostly light southeast 3-5kts during the daytime
and light and variable or calm at night.

Extended aviation discussion...

High pressure will remain over the region through Sunday with
generally VFR conditions expected, outside the usual late
night/early morning patchy river and Mountain Valley fog.


Rnk watches/warnings/advisories...
Virginia...frost advisory until 9 am EDT this morning for vaz007-009>020-
NC...frost advisory until 9 am EDT this morning for ncz001>004-
WV...frost advisory until 9 am EDT this morning for wvz042>044-507-



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