Area Forecast Discussion
Issued by NWS Blacksburg, VA
Issued by NWS Blacksburg, VA
289 FXUS61 KRNK 201924 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 324 PM EDT Sun Sep 20 2026 .WHAT HAS CHANGED... No significant changes to the forecast other than to trend even cooler for the latter half of the week. Forecast coastal storm off New England coast suggests an extended period of cold air advection Wednesday through Friday. && .KEY MESSAGES... 1) Unsettled weather expected through midweek as a front remains stalled over the region...temperatures trending noticeably cooler by Wednesday. && .DISCUSSION... KEY MESSAGE 1: Unsettled weather expected through midweek as a front remains stalled over the region...temperatures trending noticeably cooler by Wednesday. Convective allowing models have showers and storms developing along the Blue Ridge late this afternoon and moving southeast into the piedmont this evening before dissipating after sunset. A few strong storms (one or two severe) are possible, but the environment is marginal with respect to severe storm and excessive rainfall potential. MLCAPE of about 1000 J/KG is noted along the southern Blue Ridge and this will likely fuel a round of thunderstorms this evening. DCAPE of 500-800 j/KG should enhance the downdraft winds with any shower activity with potential to produce some 25 to 35 mph wind gusts with the stronger storms. Not overly concerned with excessive rainfall per ongoing drought and transient nature of any activity that develops through this evening. Once the sun goes down, expect storms to weaken. Another 24 hours of heat and humidity is expected, then we should begin to trend much cooler. A front to our north will be the clash zone for a multi-day period of shower activity with several waves of convectively induced vorticity moving along the front spawning periodic showers and thunderstorms as the front works its way through the area Monday and Tuesday. Passage of the front Monday night will bring a wind shift from the north and onset of a cooler air airmass. This cooler airmass will then deepen and become more pronounced Wednesday into Thursday as a coastal storm develops along the northern Mid Atlantic Coast with model trends developing this into a hybrid subtropical storm off the New England Coast...a feature that looks to influence our weather for multiple days in the form of strong cold air advection...winds blowing from the north through Friday. Persistent cloud cover associated with the colder airmass will then mute our temperatures with readings 10 to 15 degrees below the seasonal norm and a full 20 to 25 degrees below current observed values. During this transition, we should experience multiple days of showery weather with potential to receive 1-2" of rain. This is expected to be much needed rainfall, so unless we see the activity become stationary, we do not anticipate issuing any flood watch headlines. If there is any flooding it would be localized and during the time when the front backdoors into the area Monday night when storm cell movement along the boundary tends to be nearly stationary along Blue Ridge as it wedges into the area from the northeast. The bigger story will be the significant cool down with potential to remain stuck in the 50s and 60s Wednesday and Thursday. Cold air advection is expected to persist for multiple days so it may take until the weekend to return to readings near normal. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... Mainly VFR through this evening outside any shower and thunderstorm activity. CAMS favor the southern Blue Ridge, southwest of Roanoke this afternoon and evening for thunderstorm development which may impact routes between ROA-CLT or ROA-ATL. After the daytime deep convection fades at sunset, expect return to stable conditions with potential for overnight fog and stratus for the mountain valleys and across areas that received any rain. A late night or early morning round of showers and thunderstorms may impact WV terminals Monday morning from storm activity that crosses the Ohio Valley overnight. EXTENDED AVIATION OUTLOOK... Rain chances increase Monday and Tuesday with numerous to widespread coverage. During this time expect periods of sub-VFR conditions and potential heavy rain. Fog at night can also be expected, especially in the mountain valleys. For the latter half of the week, gusty north winds are expected per forecast of strong cyclone developing off the New England Coast. Clouds and showers from this feature may linger over the Mid-Atlantic through Friday. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ DISCUSSION...PM AVIATION...PM