Area Forecast Discussion
Issued by NWS Blacksburg, VA-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KRNK 240323
Area Forecast Discussion
National Weather Service Blacksburg VA
1123 PM EDT Sun Oct 23 2016
-- Changed Discussion --A cold front will shift southeast from the Ohio Valley into our
area by Monday morning. This front will come through dry and exit
to the south Monday afternoon. High pressure builds in behind the
front on Tuesday and Wednesday, followed by another cold front on
-- End Changed Discussion --
.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --As of 1113 PM EDT Sunday...
Expect a quiet night weather-wise. Exception will be some breezy
conditions across portions of the mountains as a 45-55 kt 8h jet
works across. At the moment forecast soundings suggest that
advisory level winds should stay at the highest ridges above 4500
ft, so mainly going to see gusts 30-40 mph across elevations in
the 2500-4000 ft range, especially along the Blue Ridge and
Alleghanys. These winds ahead of an approaching front will keep
temperatures elevated, with most having lows in the upper 40s to
lower 50s. Overall skies stay clear but some increase of mid
clouds appears likely into the Alleghanys and Greenbrier Valley
toward dawn. A sprinkle may occur as well north of Lewisburg.
Previous valid discussion...
A cold front will cross the area Monday morning. Surface winds
will will increase behind the front becoming gusty again by late
Monday morning. Once mixing begins behind the front, temperatures
will begin to rise. Downsloping on the east side of the Blue Ridge
will result in warmer temperatures and lower humidities.
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.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 230 PM EDT Sunday...
Surface high pressure will build over the region Monday night as a
dry cold front sinks south into the Carolinas. Cold air behind the
front will bring cooler than normal temperatures to the area through
the period. Afternoon highs both Tuesday and Wednesday will only
warm into the 60s. Widespread 30s are expected across the mountains
and lower 40s across the foothills and piedmont early Tuesday
morning and again early Wednesday morning. With light winds, frost
will be possible across parts of the New and Greenbrier River
Valleys and portions of the southern Alleghany Highlands late Monday
night into early Tuesday morning, and will be reflected as such in
the forecast. Frost will also be possible over parts of the New and
Greenbrier River Valleys and the Mountain Empire and Grayson
Highlands regions of southwest Virginia Tuesday night into early
Wednesday morning. However, this will not be reflected in the
forecast as October 25th will have marked the end of our
freeze/frost program for these regions for the forecast area.
From October 26th through early spring, frosts and freezes are a
normal occurrence and will not be specifically mentioned. The
freeze/frost program and growing season for our eastern counties
continues until November 15th unless there is a widespread killing
frost (temperatures below 32F) occuring before then.
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 300 PM EDT Sunday...
A warm front aloft will bring high clouds over the region Thursday
morning. By Thursday evening, a cold front will bring a line of
showers across the mountains and possibly east of the Blue Ridge
during the evening. Confidence is not high on the line surviving
east of the Blue Ridge and into a more stable environment. However,
flow becomes southwesterly, therefore scattered showers are possible
if moisture and instabilities recover with a slower moving front. An
area of weak high pressure builds in from the northwest on Friday.
Models are not in agreement with next weekends weather. The GFS
quickly brings the next cold front across the region Saturday. The
ECM has high pressure lingering into Friday night, with a warm
frontal passage Saturday followed by a cold front on Monday.
Temperatures will remain cooler than normal on Thursday, then
moderate toward normal on Friday. Next weekends temperatures will
depend on timing of each frontal passage. For now, will carry
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
As of 735 PM EDT Sunday...
Expecting VFR conditions through the period though some scattered
clouds with bases in the 1500 to 3000 ft range may occur over
BLF/LWB after fropa Monday morning.
Main issue this evening into overnight will be increase in low
level jet out of the wsw, while the surface winds stay lower in
speed. This presents some low level wind shear issues. Will have
LLWS in til mixing occurs after fropa late tonight into Monday
Behind the front winds should gust at times to 20kts, then weaken
again by the end of this TAF period.
Extended aviation discussion...
Monday night high pressure will build across the area with
Tuesday and Wednesday...Potential for river valley fog in the
mountain valleys with local vsby restrictions between 08-14Z each
morning, otherwise widespread VFR.
Thursday...Low pressure is forecast to move across the upper
midwest and into the Great lakes with a surface front crossing the
Ohio Valley. Threat for showers and sub-VFR will be possible
along this front which would impact the central Appalachians for
Thursday and Thursday night. Attm, this does not appear that it
will have a significant impact to our region. Biggest impact would
be from Ohio Valley north into Great Lakes closer to the surface
High pressure builds in from the northwest Friday, with potential
MVFR ceilings at BLF/LWB before the high arrives.
As of 400 AM EDT Sunday...
Little or no rain has fallen across the northwest North
Carolina Piedmont in the last 14 days. Conditions are becoming
increasingly dry for western North Carolina, just east of the Blue
Ridge. Drying conditions will continue for this region again
today, and for much of the upcoming work week. Passage of a dry
front early Monday may pose control problems for fire lee of the
Blue Ridge, and especially for areas which have not seen rainfall.
Greatest concern would be from Mount Airy, North Carolina, and
areas to the southwest, including Pilot Mountain. Wind gusts of 15
to 25 mph are possible Monday, coupled with humidity minimums near