Area Forecast Discussion
Issued by NWS Blacksburg, VA

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313 FXUS61 KRNK 241906 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 306 PM EDT Tue Apr 24 2018 .SYNOPSIS... An area of low pressure will head offshore tonight, but the Mid Atlantic will remain cool and damp. As this area of low pressure departs on Wednesday, an additional disturbance could bring more rain during Thursday and Friday. High pressure should arrive to provide drier conditions by the upcoming weekend. && .NEAR TERM /THROUGH WEDNESDAY/... As of 300 PM EDT Tuesday... A closed upper level trough continues to pivot toward North Carolina this afternoon. The bulk of the steady rain spinning around this trough has progressed toward eastern Virginia and left most of our area just cloudy at this time. Meanwhile, east winds continue to keep us wedged with cool and damp air. Rainfall amounts varied considerably with this event from less than a half an inch to over four inches as shown in our earlier public information statement. Minor flooding of roads was reported in Watauga County, but creeks and streams across the entire southern Blue Ridge are currently receding. Thus, the Flood Watch will be allowed to expire at 4 PM today. While there will be additional chances of rain this evening and tonight, it should become more spotty in coverage. Locations west of a line from Boone to Lewisburg could see showers lingering all night as winds shift to the northwest. Elsewhere, rain may arrive from convection forming over South Carolina at this hour that will head toward the North Carolina Piedmont and Southside Virginia by early tonight. The stable boundary layer should inhibit any chance of thunder as this activity weakens. Expect low clouds and plenty of fog by Wednesday morning due to lighter winds and plentiful surface moisture, and it may take most of the morning to see much improvement. By the afternoon, some clearing should take place. Therefore, a non-diurnal temperature curve was utilized with a slow warm up early followed by a late surge toward sunset. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... As of 245 PM EDT Tuesday... During this portion of the forecast, the region will remain within a progressive pattern of shortwave troughs rounding the base of a longer wave trough through our region. Each of these will bring the chance of showers for about a 12 to 18 hour period as they zip through the area. The first of these is slated for Thursday night into early Friday, with the second on its heels late friday into Friday night. While there is fairly good agreement in the models regarding the placement and timing of the first system, there is much more uncertainty as to the impacts for our region regarding the second of these two features. As such, confidence in showers impacting the area Thursday night into Friday is larger than that of the second system. In fact, the difference is such that likely POPs are forecast much of the area for the first system, with the second, at this point, only associated with a continuation of at least a mostly cloudy sky and no or very little precipitation to mention. Temperatures during this portion of the forecast will average very close to normal for this time of the year. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 1205 PM EDT Tuesday... During this portion of the forecast, we expect a transition from a pattern of a peristent trough across the eastern U.S. to one of an a building ridge. The result will be a primarily dry forecast and a trend towards higher temperatures. The one small chance for precipitation will be isolated showers on Saturday in the eastern part of the forecast, nearest the axis of the departing upper trough. The time period will start with high temperatures on Saturday ranging from the low to mid 60s across the mountains to the lower 70s across the Piedmont. By Tuesday, highs are forecast to range from the lower to mid 70s across the mountains to the upper 70s to around 80 degrees for the Piedmont region. Low temperatures for the weekend will average the upper 30s to lower 40s across the mountains and low to mid 40s across the Piedmont. By Tuesday morning, lows will range from the mid to upper 40s across the mountains to the upper 40s to around 50 across the Piedmont. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... As of 150 PM EDT Tuesday... Thanks to east winds bringing cool and moist conditions across the Mid Atlantic, poor flying conditions should continue at all sites for this afternoon through tonight. Ceilings and visibilities will bounce around in MVFR and IFR territory as rain moves northward ahead of a deep upper level trough approaching western North Carolina. Winds may gust up to 20 KT during the afternoon before subsiding after sunset. Rain should taper to light showers by midnight, which will set the stage for a damp Wednesday morning with high confidence in IFR/LIFR conditions due to low clouds and fog. It will take pretty much all of the morning hours for the fog and low clouds to dissipate on Wednesday. Expect a gradual improvement to IFR and MVFR throughout the day. Some clearing of the clouds may first arrive by the afternoon at DAN, which may reach VFR near the end of this valid forecast period. ROA and LYH could reach that point later in the afternoon, and BLF/LWB/BCB will likely not clear until the early evening. Extended Aviation Discussion... Unsettled weather conditions should continue for the remainder of this work week as another area of low pressure heads toward the Mid Atlantic. MVFR/IFR ceilings along with rain showers may take place during Thursday night and Friday. High pressure should build overhead to bring VFR conditions for all sites by Saturday afternoon. Good flying weather will persist through the remainder of this weekend. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...Flood Watch until 4 PM EDT this afternoon for VAZ015>017-032. NC...Flood Watch until 4 PM EDT this afternoon for NCZ001>003-018- 019. WV...None. && $$ SYNOPSIS...PW NEAR TERM...PW SHORT TERM...DS LONG TERM...DS AVIATION...PW is the U.S. government's official web portal to all federal, state and local government web resources and services.