Area Forecast Discussion
Issued by NWS Blacksburg, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRNK 212036 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 336 PM EST Sun Jan 21 2018 .SYNOPSIS... High pressure will drift southeast of the area through Monday while building northward aloft from the Southeast U.S. into the Mid-Atlantic. A warm front across the northern portion of the area will drift north into Ohio and Pennsylvania tonight into Monday. By Monday, a strong cold front will move into our region from the west accompanied by heavy rain showers and gusty winds. Relatively mild temperatures through Tuesday will give way to colder conditions again behind the cold front Wednesday, but nothing like the bitter we saw the first half of the month. && .NEAR TERM /THROUGH MONDAY/... As of 336 PM EST Sunday... High pressure centered across the Southeast will slide east tonight and Monday into the Atlantic ocean. The warm front in the Ohio Valley this afternoon will lift northeast tonight into Monday as the low pressure center moves northeast. The clockwise flow around the high pressure center is pushing warm and moist air northward into our region. The warm advection stratus is spreading east across the Appalachians. With the WSR-88d tracking some light moisture this afternoon mainly in the west, increased pops to allow for a slight chance of light rain and added the mention of spotty drizzle in the western portions tonight. Low temperatures tonight will range from around 30 degrees in the colder locations with less clouds and snow pack to the mid 40s across the higher ridges. The warmest readings will be across the ridgetops where winds will be stronger with better mixing. As the low pressure center moves to near Chicago by 00z Tuesday, a cold front will approach us from the west. The chance of showers will increase Monday afternoon into Monday evening. Rich moisture will spread north along the southern Blue ridge mountains. It is going to be mild Monday with Highs from the upper 40s in the mountains to around 60 degrees in the piedmont. && .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 336 PM EST Sunday... Warm front lifts north Sunday night into Monday with warm advection and southwest flow increasing. Will see some sun in the east Monday though cloudiness will move in aloft quickly ahead of the front. Models overall still advertising a line of showers, low topped with limited instability. Shear is high and shallow convection seems likely where winds aloft gust to the surface along the line of showers. At the moment SPC has not threat of severe, but cannot rule out some strong winds Monday evening/overnight, mainly southwest over the NC mountains/foothills. Will see area of showers lift out by midday Tuesday with lingering rain showers in the west. Colder air arrives Tuesday afternoon in the mountains with a few snow showers possible but moisture appears to dry out fast. Expect post-front winds Tuesday to possibly reach advisory levels along the Blue Ridge with 8h jet of 40-50kts and 4-6mb 6 hr pressure rises. Cloudiness may inhibit some of the stronger gusts. These winds along with potential gusty winds with showers will be mentioned in the HWO. Temperatures in the 50s to around 60 Monday cool to the 40s Tuesday in the mountains with falling temps over the higher terrain. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... As of 155 PM EST Sunday... Dry weather expect into Friday as high pressure moves across the area then sets up along the northeast, while upper trough digs across the central and northern plains. Will start to see moisture work northeast on southwest flow late Friday into Friday night. Better threat of rain showers moves in late Saturday into Sunday ahead of slow moving front, as the front becomes parallel to the upper flow. These looks like a good threat for seeing an inch or more of rain. Colder air will be delayed until Sunday night but we could see some accumulating snow showers in the mountains per strong forcing aloft with trough. Temperatures will average above normal this period, falling back toward normal or below beyond Sunday. && .AVIATION /21Z SUNDAY THROUGH FRIDAY/... As of 1246 PM EST Sunday... SCT to BKN MVFR clouds this afternoon into tonight. Widespread MVFR ceilings are expected in the west tonight. While VFR ceilings are likely in the east. Visibilities are expected to remain VFR this afternoon into tonight, then patchy MVFR and IFR fog is possible overnight into Monday morning. West to Southwest winds will continue at 4-8kt, with little if any gustiness across the ridges. Medium to high confidence in ceilings. visibilities and winds through the TAF valid period. Extended Discussion... Sub-VFR conditions are expected to expand from west to east ahead of a strong cold front Monday afternoon. While there may be scattered light to moderate rain showers out ahead of the front, of greater concern is a line of convective showers, possibly a QLCS with isolated embedded thunderstorms, that will accompany the front and a strong 60kt associated LLJ. Consequently, the greatest concern with these showers will be strong wind gusts, potentially of 45-50 mph or possibly even greater for a short duration in the Monday evening/early Tuesday morning time frame. Strong gusty northwest winds are expected behind the front Tuesday into Wednesday. VFR ceilings should return to the Piedmont by Tuesday afternoon, but MVFR ceilings with low clouds and potentially -SHSN can be expected further west across the Alleghanys, and possibly as far east at times as BCB. High pressure and VFR conditions along with diminishing winds should return to the entire area by Wednesday. Dry weather is expected Thursday and Friday, with moisture returning from the southwest on Saturday. && .CLIMATE... As of 1230 PM EST Sunday... Sunday 01/21/2018 Site MaxT Year HiMin Year KBLF 60 1999 48 2017 KDAN 68 1959 56 1954 KLYH 72 1932 51 1927 KROA 74 1932 51 1959 KRNK 59 1954 42 1954 && .EQUIPMENT... As of 325 PM EST Friday... NOAA Weather Radio, WXL60 (Roanoke Transmitter) which broadcasts at 162.475 MHz remains off the air. The phone company reported that the circuit line had been cut and will take until Monday January 22nd to fix it. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...RAB NEAR TERM...KK SHORT TERM...WP LONG TERM...WP AVIATION...KK/RAB CLIMATE...KK EQUIPMENT...WP is the U.S. government's official web portal to all federal, state and local government web resources and services.