textproduct: Morristown

KEY MESSAGES

Updated at 627 PM EST Sat Dec 13 2025

- Light snow accumulations expected across the high terrain of East Tennessee and southwest Virginia overnight into Sunday morning.

- Bitter cold will surge into the area for Sunday through Monday morning. Please see the Cold Weather Advisories for additional details.

- Warming trend begins Tuesday with above normal temperatures by mid to late week. Conditions will be dry during this time.

DISCUSSION

Issued at 1236 PM EST Sat Dec 13 2025

A broad upper level trough remains in place over much of the central and eastern CONUS. Shortwave energy translating through the synoptic feature tonight into Sunday will sharpen the troughing as a surface front progresses through the region. Some light ra/sn will occur during the overnight hours as this energy translates through the central and southern Appalachians, however, the greatest probabilities for light snow accumulation will be limited to higher terrain of the East Tennessee mountains and southwest Virginia. Overall, moisture in the DGZ is lacking and better northwest flow does not initiate until the bulk of the moisture is departing the region. Will cover this with an SPS for now, ending it at midnight to allow for the next forecast desk to make any additional considerations.

The main concerns will be well below normal temperatures advecting into the region as winds veer NNWly and become gusty behind frontal passage. Temperatures around 20 degrees below normal are largely expected across the region Sunday into Sunday night. A Cold Weather Advisory has been issued for the Cumberland Plateau, southwest Virginia, and our East Tennessee mountain zones starting around sunrise tomorrow morning. The gusty winds and well below normal temperatures will result in wind chill values around zero, to as low as 10 below zero in the highest terrain of the mountains. By late Sunday afternoon, the remainder of the valley locations are introduced to the Advisory as cold air continues to filter into the region. Overnight lows in the low teens to single digits will be widespread. Many valley locations will see wind chills in the single digits to near zero.

Cold Weather Advisory products will come to an end shortly after daybreak Monday, when a gradual warming trend is expected into the mid-week as the anomalous troughing ejects northeast and H5 heights slowly recover. For Wednesday night through Friday, the main storm track will be across the northern third of the nation. The fast but more zonal flow will quickly move a series of short-waves with associated frontal boundaries moving across the region. Ensemble cluster analysis shows differences in timing of systems but overall increasing chances of precipitation are expected towards the latter half of the week.

AVIATION

(00Z TAFS) Issued at 627 PM EST Sat Dec 13 2025

A mix of rain and snow, mainly near TRI and TYS, is expected as a trough moves through overnight. MVFR CIGs are likely at all terminals until mid morning. Winds will become more northwesterly and gusty in the early morning hours as a boundary moves through. Gusts will be a bit higher once the clouds thin out in the morning. Showers will start out as rain around midnight before changing to light snow late tonight. Little to no accumulation is expected at TYS. TRI may get up to half an inch.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 26 32 17 41 / 20 0 0 0 Knoxville McGhee Tyson Airport, TN 24 30 13 39 / 40 10 0 0 Oak Ridge, TN 21 27 12 37 / 30 0 0 0 Tri Cities Airport, TN 21 27 8 35 / 70 10 0 0

MRX WATCHES/WARNINGS/ADVISORIES

NC...Cold Weather Advisory from 5 PM Sunday to 10 AM EST Monday for Cherokee-Clay.

TN...Cold Weather Advisory from 5 PM Sunday to 10 AM EST Monday for Anderson-Bradley-East Polk-Grainger-Hamblen-Hamilton- Hancock-Hawkins-Jefferson-Knox-Loudon-McMinn-Meigs-North Sevier-Northwest Blount-Northwest Carter-Northwest Cocke- Northwest Greene-Northwest Monroe-Rhea-Roane-Sullivan-Union- Washington TN-West Polk.

Cold Weather Advisory from 7 AM EST /6 AM CST/ Sunday to 10 AM EST /9 AM CST/ Monday for Bledsoe-Blount Smoky Mountains- Campbell-Claiborne-Cocke Smoky Mountains-Johnson-Marion- Morgan-Scott TN-Sequatchie-Sevier Smoky Mountains-Southeast Carter-Southeast Greene-Southeast Monroe-Unicoi.

VA...Cold Weather Advisory from 5 PM Sunday to 10 AM EST Monday for Scott VA.

Cold Weather Advisory from 7 AM Sunday to 10 AM EST Monday for Lee-Russell-Washington VA-Wise.