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Area forecast discussion 
National Weather Service Blacksburg Virginia
757 PM EDT Friday may 22 2015

no major weather systems will affect our region for the next
several days as high pressure off the middle Atlantic coast stays
in control of our weather. This will bring a warming trend with
heat and humidity on the increase throughout the Holiday
weekend...with just an outside chance for a late day shower or
thunderstorm west of the Blue Ridge by Monday or Tuesday. As the
high moves further to the east...our chances for precipitation
will be on the increase as we head toward the middle of next week.


Near term /through Saturday/...
as of 330 PM EDT Friday...

Visible satellite pics indicate lots of sunshine for the region
late this afternoon...but a band of clouds with some shower
activity has formed along an approaching front to our north. Model
guidance has had a handle on this feature for a good while now and
expect the front to wash out as it enters the area early tonight.
Thus expect the only affects we will feel from the front will be
some increase in cloudiness as any precipitation will dissipate
before it reaches US.

On Saturday surface high pressure will drift to our east and set
up a southeasterly return flow which will warm US up a few
degrees from today and start to increase humidity levels a bit. A
stray sprinkle is possible by Saturday afternoon along the Blue
Ridge with the southeasterly flow running up the Blue Ridge in the
remnants of the old frontal zone...but any probability of precipitation will be below
mentionable levels and it certainly does not look like a reason to
cancel a picnic so will continue with a dry forecast through the
first part of the weekend.

Lows tonight are a bit challenging as any clouds associated with
the front dropping down will inhibit radiational cooling. Still
believe it will get quite chilly with generally low/middle 40s west
of the ridge and middle/upper 40s east. Some of the normally cooler
locations west of the ridge may reach the upper 30s by daybreak
but believe expected dewpoints and some degree of clouds will
prohibit any frost formation and mitigate any threat to tender


Short term /Saturday night through Monday night/...
as of 330 PM EDT Friday...

Time to fire up the barbie!

High pressure surface and aloft will build across the eastern Continental U.S.
Through the Holiday weekend...temperatures trending progressively
warmer. With increasing subsidence...shower production will be kept
to a minimum...thus expecting mainly dry weather through Monday.


Long term /Tuesday through Friday/...
as of 330 PM EDT Friday...

Summerlike pattern to close out the last week of may.

The upper level ridge will remain in place through the week...the
actual surface high becoming anchored off the southeast Atlantic
coast. This will place our forecast area in an in increasingly muggy
pattern with dewpoints climbing into the 60s to compliment the
upward trend in temperatures...daytime highs in the 80s/near 90.

The warm/humid conditions will promote diurnally driven deep
convection. Forcing will be mainly over the mountains Tuesday and
Wednesday then areawide Thursday and Friday as a weak cold front
tries to cross the mountains during the latter half of the week.

Overall threat for severe weather during the week appears to be
low...dynamic support lacking.


Aviation /00z Saturday through Wednesday/...
as of 745 PM EDT Friday...

VFR conditions expected through the taf valid period. A weak
west-east oriented cold front was drifting down from the north
this evening...associated with scattered-broken middle clouds and a few
showers across northern WV. These showers will not make it to the
taf sites...but a few of the remnant clouds will. Models show the
leftover frontal boundary stalling across the central part of the
County Warning Area Saturday and moisture trapped in the 050-070 range could yield
scattered-broken clouds during diurnal heating...mainly west of the Blue
Ridge. Occasional sct250 as well from upstream convective debris
spilling over the upper ridge just to our west. The air mass is
quite dry...but radiational cooling will be relatively effective
tonight...which could yield some MVFR br at lwb/bcb in the 09z-12z
time frame...otherwise VFR through the taf valid period.
Winds...northwest 5-7kts through 04z...then veering through NE-southeast during
the day Saturday as surface high pressure moves off the coast. Speeds
remaining mostly 7kts or less through the taf valid period.

High confidence in VFR ceilings through the taf valid period.
Madame to high confidence in visibilities through the taf valid period.
Medium confidence in wind direction through the taf valid
period...medium to high confidence in wind speed.

Extended aviation discussion...

VFR conditions expected Sunday into early next week. High pressure
will gradually move offshore and southwest winds around the high
will result in some increase in moisture early next week. This may
bring a gradual increase in mountain afternoon and evening showers
and thunderstorms...especially by later Tuesday...when periods of
MVFR could occur mainly Blue Ridge west. Otherwise...VFR Monday
and Tuesday outside of any late day convection.


Rnk watches/warnings/advisories...


near term...mbs
short term...PM
long term...PM

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