301 FXUS61 KRNK 160249 CCA AFDRNK Area Forecast Discussion...CORRECTED National Weather Service Blacksburg VA 1049 PM EDT Thu Jul 15 2021 .SYNOPSIS... Persistent summer pattern continues tonight and Friday then a front approaches the area on Saturday with more numerous thunderstorms. The passage of this front will introduce slightly cooler temperatures for next week, and less humidity. && .NEAR TERM /THROUGH FRIDAY NIGHT/... As 947 PM EDT Saturday... No changes expected to the current forecast package. Hot temperatures with an isolated shower or storm Friday... Some slight adjustments to temperature to reflect readings still in the 80s around the urban centers and off to the east over the Piedmont as of 945PM. Otherwise mostly clear to partly cloudy skies tonight with dry air holding strong in our mid to upper levels of the atmosphere per the 0z sounding here at RNK. Relatively calm winds and moist dewpoint values will keep patchy to dense areas of river valley fog around through early Friday morning. Fog should burn off after 9-10am with mostly sunny to partly cloudy skies Friday afternoon. Similar to today shower and thunderstorm activity looks to be fairly sparse and mainly confined to the western mountains during the afternoon/early evening hours. Severe weather is not expected at this time, but any storm could pack a punch with locally gusty winds, brief heavy rainfall, and frequent lightning concerns. By Friday night, any shower and storm activity will come to an end with the loss of daytime heating. Our front will start to near the area from the west beyond this point with better chances for storms heading into the weekend. Friday's high temperatures will climb into the mid to upper 80s in the west with low to mid 90s out east. Have plenty of fluids and take plenty of breaks if you are going to be spending extended time outdoors. Confidence remains high in the near term. Previous discussion... Only subtle differences in the overall weather pattern for tonight and Friday. 500MB flow shifts from west to southwest. No organized forcing so another day with low level convergence and orographics sparking isolated to scattered afternoon thunderstorms. Best chance into the evening will be along the southern Blue Ridge and in the piedmont along the Virginia/North Carolina border. For tonight more fog expected in the river valleys west of the Blue Ridge. GFS had forecast 850mb temperatures as high as +22 Friday afternoon. Will be leaning slightly above MAV guidance for maximum temperatures. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... As of 120 PM EDT Thursday... A cold front will drop southeast Saturday and reach the western mountains Saturday night. Numerous showers and thunderstorms will develop Saturday afternoon into Saturday evening in advance of this front. Dynamics do not look overly impressive, so not expecting widespread severe storms, but should be enough for some stronger storms, with damaging winds and heavy rain the main threat. Front tries to clear the area Saturday night, but being mid-July, thinking it will struggle to completely push through. So expecting the front to stall across the area, once again allowing for afternoon rain and thunderstorms through Sunday evening. Saturday to be the warmest day with low 90s in the Piedmont, 80s in the mountains. Sunday, daytime highs should be five to seven degrees cooler owing to lingering cloud cover and afternoon rain/storms. Overnight lows remain mild. && .LONG TERM /MONDAY THROUGH THURSDAY/... As of 120 PM EDT Thursday... Could still be dealing with the stalled frontal boundary into Monday as model guidance is still keeping it within the general vicinity of the CWA. At the moment, best chances for rain/storms on Monday will be along and south of the NC/VA border. Drier conditions look to return by Tuesday as the stalled front finally gets shoved south as the upper-level lobe across the Great Lakes region pushes another wave south. Mostly dry conditions to continue into late next week, with the exception of only some isolated diurnal showers/storms, mainly for the mountains. Temperatures near normal for the forecast period, but with a slight warming trend through next week. && .AVIATION /02Z FRIDAY THROUGH TUESDAY/... As of 710 PM EDT Thursday... VFR through the period. Exception will be MVFR to LIFR fog in the valleys overnight. At this time have a few hours of LIFR conditions at KLWB and KBCB after 07Z/3AM. Any fog will dissipate by 13Z/9AM on Friday. Little change in the weather pattern in expected on Friday. Isolated to scattered thunderstorms will begin to develop after noon, with best coverage south of a GEV-SIF line, and not enough to warrant mention in the tafs. Above average confidence for ceiling, visibility and wind. Extended Aviation Discussion... A front will bring numerous showers/storms for Saturday and Sunday with greater coverage of sub-VFR ceilings and visibilities. By Tuesday the boundary will be south of the region with cooler and drier weather and a return to widespread VFR conditions. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AMS NEAR TERM...AMS/ET/WP SHORT TERM...BMG LONG TERM...BMG AVIATION...AMS/PM/WP