Area Forecast Discussion
Issued by NWS Blacksburg, VA

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000 FXUS61 KRNK 100742 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 242 AM EST Sun Dec 10 2017 .SYNOPSIS... Northwest flow pattern remains with us this week with colder temperatures and occasional bouts with mountain snow showers/flurries. A stronger system dives in by Tuesday with very cold temperatures and low wind chills expected by Wednesday morning. && .NEAR TERM /THROUGH TONIGHT/... As of 215 AM EST Sunday... Main shortwave/vort tracking over southern WV/Alleghanys early this morning will be east of us before dawn, with a downward trend in snow showers/flurries through mid morning before ending. Will keep headlines going through mid morning. Another one half to 1 inch of snow will occur in the higher ridges, with a dusting as far east as the New River Valley ridges. Strongest pressure gradient and pressure rises are occurring as of this writing and seeing a few gusts over 40 mph in the mountains of NC. Should see gusts slowly diminish into late morning, but look for the winds to stay brisk to keep a definitive chill in the air through lunchtime. Highs today will be similar in the mountains to Saturday with lower to mid 30s, while the piedmont with more sunshine will reach the upper 30s, which is still around 10-12 degrees below normal. Most will see sunshine by this afternoon. Tonight, another weak disturbance in the persistent upper trough will rotate through the area, but mainly seeing an increase in clouds, but cannot rule out a few flurries in the WV mountains. Ridgetops look to see another round of gusty winds, though not as high as system is weaker, so looking at 20-30 mph gusts at elevations above 3000-3500 feet. Lows tonight will be in the 20s. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... As of 225 AM EST Sunday... Fast flow continues this period with next clipper arriving Monday night-Tuesday, with mainly snow showers over the mountains. Again the main track of the surface low and upper vort will tend to take best lift northwest of our forecast area but enough west/northwest upslope to bring a couple inches to the mountains of Greenbrier with an inch or less as far south as the NC High Country though again track favors less south of the WV/VA border. Flurries could reach as far east as the Blue ridge, especially heading into Tuesday night as a more potent shortwave enters the central Appalachians. Temperatures moderate Monday with highs in the lower to mid 40s, but cool back to the lower to mid 30s Tuesday in the mountains, to lower to mid 40s east. Big surge of cold air will send lows Tuesday night into the teens areawide, as 8h temps fall to -14 to -16C. Potential wind chill headlines for Tuesday night-Wednesday morning exist as they drop toward zero to minus 10 in the mountains. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 345 PM EST Saturday... Upper air pattern is forecast to remain amplified with cold upper level trough over eastern North America. Embedded short waves passing through the general flow pattern will result in reinforcing shots of cold air and potential for mountain snow showers and flurries. This will also maintain elevated wind speeds with brisk northwest northwest winds across the ridges. Temperatures will favor the colder side of normal from Wednesday through Friday...trending back closer to normal for the weekend as the upper flow trends more zonal. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... As of 1145 PM EST Saturday... High confidence that widespread MVFR ceilings and numerous snow showers will persist overnight in the mountains. Bands of heavier snow combined with blowing snow will create brief periods of IFR conditions at KBLF and possibly KLWB. Expect some MVFR cigs to make it to KBCB but any precipitation will likely be flurries. Wind gusts will start to increase early tonight with gusts at or above 30kt for KROA through mid morning. Gust conditions will spread east of the Piedmont Sunday morning as diurnal heating mixes the boundary layer and allows higher momentum air to reach the surface. Upslope snow showers wind down to flurries Sunday morning, but gusty conditions will persist before gradually slackening during the afternoon. Extended Discussion... VFR conditions then return Sunday evening through Monday. Next chance for sub-VFR conditions is with a clipper system Tuesday, particularly in the western mountains. The sub-VFR could linger into Wednesday as northwest flow continues. && .EQUIPMENT... The observation at KMTV, Martinsville, Virginia is out of service. Restoration time is unknown. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...Winter Weather Advisory until 10 AM EST this morning for NCZ001>006-018>020. WV...Winter Weather Advisory until 9 AM EST this morning for WVZ508. && $$ SYNOPSIS...WP NEAR TERM...WP SHORT TERM...WP LONG TERM...PM AVIATION...AMS/MBS EQUIPMENT...AMS is the U.S. government's official web portal to all federal, state and local government web resources and services.