Subj : Area Forecast Discussion For Tri Cities, TN/VA To : All From : Sean Dennis Date : Sun Dec 07 2025 19:00:01 173 FXUS64 KMRX 071749 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 1249 PM EST Sun Dec 7 2025 ....New DISCUSSION, AVIATION... ..KEY MESSAGES... Updated at 1246 PM EST Sun Dec 7 2025 - Overnight expect precipitation to move in. Light snow accumulations are expected, primarily across the higher elevations of northeast Tennessee and southwest Virginia. - A Winter Weather Advisory has been issued for late tonight into Monday. The Monday morning commute in these counties could be impacted by accumulating snow, or reduced visibilities from falling snow. && ..DISCUSSION... Issued at 1246 PM EST Sun Dec 7 2025 Primary forcing for precipitation will be associated with a midlevel shortwave trough, with model guidance showing little in the way of organized surface forcing. Therefore, precipitation amounts are expected to remain light throughout the event. Measurable precipitation should start generally between sunset and midnight as the column slowly moistens closer to the surface. By early Monday morning, cold air advection strengthens behind a weak low-level trough and attendant surface cold front, resulting in falling temperatures and a transition to snow across northern portions of the forecast area. This transition will be most notable in southwest Virginia and the eastern Tennessee mountains. Outside of the highest terrain, accumulations will be fairly limited. In the higher elevations of northeast Tennessee, persistent northwest flow in the wake of the shortwave may yield localized accumulations of 1–3 inches through Monday evening, primarily along mountain peaks near the North Carolina border. While much of the counties look to see snowfall totals technically remain below Advisory criteria, have opted to issue a Winter Weather Advisory since the ridge lines could see up to 3 inches... In addition the Monday morning commute could very much be impacted as light to (possibly at times) moderate snow is coming down. This is a very low end advisory, but Monday morning driving conditions are the main concern with this event. A generally zonal flow regime is anticipated through midweek, supporting modest warming with highs reaching the 50s by Wednesday. The next synoptic system approaches late in the week, with temperatures initially mild ahead of the front, followed by a pronounced cold advection behind the low and frontal passage Thursday into Friday. A much colder air mass is forecast to settle in for the weekend, with morning lows potentially in the teens and daytime highs limited to the 20s and 30s. && ..AVIATION... (18Z TAFS) Issued at 1246 PM EST Sun Dec 7 2025 Low confidence forecast. Clouds are extremely stubborn to clear out of KCHA, but should start to break up in the next couple of hours. Cold rain moves in overnight and will likely drop conditions down below MVFR categories, but low confidence on how far they drop with some guidance going to VLIFR and others barely dipping below MVFR. && ..PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 41 50 29 52 / 40 10 0 0 Knoxville McGhee Tyson Airport, TN 38 44 28 50 / 40 30 0 0 Oak Ridge, TN 38 45 27 48 / 30 20 0 0 Tri Cities Airport, TN 35 40 27 44 / 50 80 10 0 && ..MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...Winter Weather Advisory from 1 AM to 7 PM EST Monday for Johnson- Southeast Carter-Unicoi. VA...Winter Weather Advisory from 1 AM to 7 PM EST Monday for Russell- Washington VA-Wise. && $$ DISCUSSION...99 AVIATION...99 --- MBSE BBS v1.1.6 (Linux-x86_64) * Origin: Outpost BBS * Johnson City, TN (618:618/1) .