Area Forecast Discussion
Issued by NWS Blacksburg, VA

Current Version | Previous Version | Graphics & Text | 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 220014 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 814 PM EDT Mon May 21 2018 .SYNOPSIS... A southerly flow will continue to push warm and humid air into our region early this week. The nearly stationary front to our north will finally push south across our area Wednesday. High pressure will follow the front Wednesday night and keep the area mostly dry through Friday. && .NEAR TERM /THROUGH TUESDAY/... As of 200 PM EDT Monday... A blocking ridge centered over Bermuda stretches westward to cover portions of the southeast and Mid Atlantic states tonight. This ridge is expected to sink south Tuesday, losing its influence on the region and allowing an upper level trough and a cold front to approach the area from the northwest. Over the Gulf states north into the Tennessee Valley, a weak upper level trough will continue to draw Gulf and Atlantic moisture northward into the area tonight and tomorrow. From this afternoon into this evening, storms will track from the southeast to the northwest. Tomorrow the steering flow shifts with storms moving from the southwest to the northeast. All storms will be slow moving and with the addition of tropical moisture, heavy downpours are likely this afternoon and evening and again tomorrow afternoon and night. Since the ground remains wet and creeks, streams and rivers are elevated, there is a chance for renewed flooding this evening and tomorrow. As far as severe threat, model soundings suggest very moist layer with SBCAPEs around 1000 J/KG this afternoon. Cannot rule out some isolated wet microbursts but main threat is localized flash flooding. Temperatures will remain muggy overnight with readings in the 60s. Temperatures Tuesday will range in the 70s across the mountains to low to mid 80s east. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 300 PM EST Monday... Scattered to widespread showers and thunderstorms are expected Tuesday evening into early Wednesday as an upper level disturbance pushes across the central Appalachians toward the coast ahead of an approaching cold front. Right now, instability appears to be modest with this disturbance such that it wouldn`t be a surprise to see a few cells become strong to severe before midnight Wednesday, mainly across the Piedmont, but the threat of widespread severe storms overall appears limited. The cold front will sink southward, advancing to the Interstate 81 corridor around dawn before loosing speed somewhat as it continues a southward drift. Believe we will see a redevelopment of showers across the mountains in the northwest flow upslope regions, however instability will be limited. Greater instability will be found in the vicinity of the front across extreme southern Virginia and northern North Carolina, where scattered strong storms may redevelop with afternoon heating where CAPEs may exceed 2000 J/Kg. Outflows from any of these storms will help to push the front further southward by evening, clearing the boundary through our area after sunset Wednesday. High pressure will shift toward New England Wednesday night, causing winds across the Mid Atlantic to swing more easterly by Thursday morning. Though instability will be very modest within the weak high pressure wedging across the region, may see a few showers/isolated storms develop along the Blue Ridge with afternoon heating as marine air off the Atlantic is forced into the mountains. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 300 PM EST Tuesday... Winds will shift more southerly on Friday as high pressure slides off shore. Though moisture and instability will remain limited, expect slightly greater coverage of spotty, daytime heating-driven showers and thunderstorms. Coverage of showers and thunderstorms will increase during the weekend as a warm front lifts northward through the mid Atlantic, bringing a return of deeper moisture from the Gulf coast region. Afternoon temperatures will range from the mid 70s to the mid 80s each day, while overnight lows will generally be in the 60s areawide. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
As of 800 PM EDT Monday... Numerous thunderstorms will continue east of a KDAN to KLYH line this evening where the air mass is still unstable. KLYH will be starting the TAF forecast period with MVFR conditions and erratic winds due to a strong thunderstorms. Hi-Res guidance and HRRR indicated areal coverage of showers and thunderstorms will diminish after 06Z/2AM. High confidence of MVFR fog overnight in areas where there has been rain this afternoon across much of southwest Virginia, northern North Carolina and southeast West Virginia. Medium confidence that KLWB will lower to LIFR in dense fog after 08Z/4AM. Ceilings across much of the region will lower to IFR late tonight. The fog and stratus that forms overnight will be gone by 12-14Z/8-10AM Tuesday. More thunderstorms are expected Tuesday afternoon and evening. Confidence low as to the location where the storms will first develop. MVFR conditions are likely with any of the storms, otherwise high confidence of a scattered to broken VFR stratocumulus layer. .Extended Aviation Discussion... MVFR showers and thunderstorms are likely again Wednesday. Conditions are will be drier and are expected to be VFR Thursday and Friday.
-- End Changed Discussion --
&& .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...RCS NEAR TERM...RCS SHORT TERM...NF LONG TERM...NF AVIATION...AMS/RCS is the U.S. government's official web portal to all federal, state and local government web resources and services.