Subj : Area Forecast Discussion For Tri Cities, TN/VA To : All From : Sean Dennis Date : Mon Dec 08 2025 07:00:02 202 FXUS64 KMRX 081140 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 640 AM EST Mon Dec 8 2025 ....New AVIATION... ..KEY MESSAGES... Updated at 635 AM EST Mon Dec 8 2025 - Precipitation moves in tonight, with light snow accumulations expected across the higher elevations of northeast Tennessee and southwest Virginia. - A Winter Weather Advisory continues 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 1242 AM EST Mon Dec 8 2025 WV imagery shows a shortwave trough located over northern MS/West TN. Precip ahead of this trough will spread across our area through the night. Initially, low level temperatures indicate rain, except for the highest mountain peaks above 5000 ft. A cold front is located just to our west, and will start to push southeast late tonight as high pressure builds toward the region from the Great Lakes. As the column cools behind the front and the upper trough moves overhead, there will be some saturation getting into the dendrite growth zone along with falling surface temperatures, allowing for some snow to fall in northern sections. This occurs around 12-15Z. SW VA and the mountains of E TN will continue to see light snow accumulations through the day, while there may be more of a rain/snow mix in northern TN Valley locations, such as the Tri- Cities area. Not much has changed with the model depictions of likely snow accumulations - outside of the highest terrain, accumulations will be fairly limited to less than 1 inch. In the higher elevations of northeast Tennessee and SW VA, persistent northwest flow through Monday 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. Snow probs from the HREF are 80-90% chance for 2 or more inches, and the NBM is around 50%. Therefore, the mountain zones down to Blount County will be added to the Winter Weather Advisory. The timing of the changeover to snow in the morning could impact the morning commute in parts of SW VA and NE TN, with some roads getting covered in the mountains by the end of the day. No major changes to the rest of the forecast. 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. Precip chances with this system appear to be trending down, and are mainly across our northern sections; QPF is very light as well. 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... (12Z TAFS) Issued at 635 AM EST Mon Dec 8 2025 Aviation conditions have largely deteriorated to MVFR or even IFR across the region as rain continues to move through. CHA is MVFR and is currently expected to stay mainly at that level. For TYS and TRI, periods of IFR remain possible over the next several hours. These chances extend longest for TRI because of rain lingering longer into the afternoon. Winds will also gradually increase from the north to northwesterly direction. A return to VFR is currently anticipated by later this evening, but it's possible for MVFR to remain. && ..PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 48 28 51 36 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 44 27 49 37 / 40 0 0 0 Oak Ridge, TN 44 26 47 36 / 30 0 0 0 Tri Cities Airport, TN 40 25 43 30 / 90 10 0 0 && ..MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...Winter Weather Advisory until 7 PM EST this evening for Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky Mountains-Southeast Carter-Southeast Greene-Unicoi. VA...Winter Weather Advisory until 7 PM EST this evening for Russell- Washington VA-Wise. && $$ DISCUSSION...DGS AVIATION...BW --- MBSE BBS v1.1.6 (Linux-x86_64) * Origin: Outpost BBS * Johnson City, TN (618:618/1) .