Area Forecast Discussion
Issued by NWS Blacksburg, VA

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000 FXUS61 KRNK 121501 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 1101 AM EDT Mon Mar 12 2018 .SYNOPSIS... A complex storm system was developing across the southeastern U.S. This storm system will increase in strength and move northeast toward the North Carolina coast later in the day Monday. Winter Storm Warnings and Winter Weather Advisories remain in effect through midnight for all of the forecast area. An Arctic air mass will spread toward the region during midweek behind the departing snow storm, bring gusty winds, below freezing temperatures, and upslope snow showers. Much warmer temperatures and a chance of rain will arrive for the weekend as the upper air pattern undergoes some significant changes. && .NEAR TERM /THROUGH TONIGHT/... As of 1051 AM EDT Monday... Winter storm warnings and winter weather advisories remain in effect Midnight tonight. Refer to latest PND and LSR for snowfall totals on winter storm. One of the higher snowfall totals in our CWA was near Lerona where near 8 inches was reported by the public. The NAM did pick up on the mesoscale band which ramped up snow amounts this morning. Shaped the near term grids towards a blend of the NAM, Hires- ARW-East and HRRR with ensemble temperature profile using weather tool for PTYPE. Modified surface temperatures utilizing the latest surface obs, their trends and shaped towards the NamDNG/NBM to capture cooling with precipitation especially in the southeast. Check out storm total snow for details on accumulations and locations. The main energy transferring to the coastal low this afternoon which will deepen and lift northeast along the East Coast. The northwest flow on backside of the low will result in mountain upslope flow tonight into Tuesday. More changes later this morning... && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... As of 330 AM EDT Monday... Active pattern through midweek as a high amplitude, blocky pattern keeps a deep trof lodged over the eastern US through the period. This will keep us locked into persistent northwesterly flow with robust packets of short wave energy rotating through the upper trof, and ample low level moisture with teleconnections back to the Great Lakes. The end result will be periods of upslope snow showers west of the Blue Ridge, especially at the higher elevations, with accumulations which may require advisories. East of the Ridge will see general downsloping conditions with fair weather. Additionally, conditions will be quite blustery with a notable increase in winds starting on Wednesday which may eventually require wind advisories, mainly west of the Ridge. Will highlight these parameters in the hazardous weather outlook and monitor through later model runs. Temperatures will be well below normal, though there will be some moderation by Thursday. && .LONG TERM /FRIDAY THROUGH SUNDAY/... As of 300 PM EDT Sunday... The highly amplified flow pattern across the eastern U.S. is expected to flatten later in the week as a new western trough begins to develop. With heights/thicknesses rising this will allow temperatures to rebound closer to mid-March climatology by Friday. 12z GFS depicts a weak short-wave approaching the Ohio Valley by Friday crossing the Appalachians into Saturday with chances for rain (not snow) per warmer thermal profiles. Likely to be changes in the details as to track/timing/intensity that far out so just went chance pops for the Fri-Sat time period. Canadian/EC offer quite different solutions at this point. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... As of 745 AM EDT Monday... The awaited snow storm is well under way with 1-3 inches many spots west of the Blue Ridge. Conditions will continue to deteriorate overnight and into Monday morning. Significant aviation operational impact expected accumulating wet snow (some sleet). High confidence in flight categories trending predominantly IFR to LIFR with obstructed ridges. Most sites will see IFR or worse ceilings by 08Z/09Z continuing in this range until at least early afternoon, before some eastern sites see improvement to MVFR, but IFR will likely remain in place west of the Blue Ridge through most if not all of the TAF valid period. Visibilities in wet snow may trend 1/4SM to 1/2SM in heavier snow at times through this morning. With the exception of Danville and potentially Lynchburg, snow-covered runways should be common, but the best chance at KBCB/KBLF/K:WB. Moderate to heavy morning snow will taper to light snow and snow showers mainly west of the Blue Ridge during the evening as the surface low moves off the coast and winds begin to back to the northwest. East to northeast winds will back to northeast through northwest through the TAF valid period. Speeds 4-6 kts increase to 6 to 10 kts. Moderate to high confidence on ceilings, visibilities, and winds through the TAF valid period. Extended Aviation Discussion... Conditions should begin to improve from west to east by evening Tuesday. VFR should return to the Piedmont by Tuesday, while the western mountains will see lingering MVFR conditions with upslope clouds and snow showers through Wednesday. Strong gusty northwest winds are also expected late Tuesday into Wednesday as deep low pressure develops off the northeast U.S. coast. All conditions are expected to improve by the weekend with a notable warming trend. && .EQUIPMENT...
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As of 1100 AM EDT Monday... The Mount Jefferson NWR will remain off the air until further notice awaiting a part that was damaged during a high wind event/power outage over a week ago. Inclement winter weather could further delay the repair of this site until midweek. Please seek alternate sources for your weather information, such as adjacent NWRs (Roanoke, Hinton WV, Lynchburg, South Boston, Johnson City TN, Beckley WV, etc.), commercial sources, and the internet. You can always access our web page at
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&& .RNK WATCHES/WARNINGS/ADVISORIES... VA...Winter Storm Warning until midnight EDT tonight for VAZ010>020- 022>024-033>035. Winter Weather Advisory until midnight EDT tonight for VAZ007- 009-032-043>047-058-059. NC...Winter Storm Warning until midnight EDT tonight for NCZ001-002- 018. Winter Weather Advisory until midnight EDT tonight for NCZ003>006-019-020. WV...Winter Storm Warning until midnight EDT tonight for WVZ042>044- 507-508. && $$ SYNOPSIS...RAB NEAR TERM...KK/RAB SHORT TERM...MBS LONG TERM...MBS/PC AVIATION...KK/RAB/WERT EQUIPMENT...RAB is the U.S. government's official web portal to all federal, state and local government web resources and services.