textproduct: Morristown

KEY MESSAGES

Updated at 728 AM EDT Mon Mar 16 2026

- A line of strong showers and thunderstorms just ahead of a strong cold front, will sweep through the forecast area before daybreak Monday.

- Conditional tornado threat continues through early morning hours for the southern Cumberland Plateau and southern Tennessee Valley areas. Elsewhere, damaging winds remain the primary concern.

- Behind the front, very cold air surges in Monday and continues across the area through Wednesday morning. Light snow accumulations appear likely in higher elevations of the East Tennessee mountains and parts of southwest VA Monday afternoon and night. Light snow showers could even occur down to the valley floor, but no accumulations are expected there.

- Gradual warming trend with mostly dry conditions mid week into the weekend.

DISCUSSION

Issued at 139 AM EDT Mon Mar 16 2026

Main focus of the forecast discussion is the incoming line of storms and associated severe weather threat overnight, followed by the stark temperature change and possibility of snow tomorrow and tomorrow night.

First off, the severe storm chances. Current regional radar imagery shows a solid line of thunderstorms stretching along a cold front from central Indiana, south through Middle Tennessee and into northern Mississippi as of 10:30 PM EDT this evening. This will continue to shift east overnight, arriving in the plateau areas by around 2-3 AM EDT, and pushing east of our CWA by 5-6 AM EDT. In terms of severe threat, it remains a conditional threat for both damaging winds and tornadoes. Surface obs and mesoanalysis show LCLs are higher than you would want to see across Middle Tennessee and adjacent areas largely due to lower dewpoints (low to mid 50s). However as the low level jet and surface flow have strengthened, a narrow corridor of +60F dewpoints have surged northward just ahead of the cold front and nearby discrete supercells. Further east, ESE flow across South Carolina and northern Georgia is also bringing in some upper 50s to low 60s dewpoints to near the southern TN valley. Models suggest the southern Cumberland plateau and southern Tennessee valley will see a similar surge of low level moisture, and subsequently surface based CAPE, just ahead of the line. As such, there continues to be a conditional threat for some tornadic activity, along with a threat of significant damaging winds, south of the I-40 corridor and mainly west of I-75 through 06-08z (or 2-4 AM EDT) as that line moves in. That said, one thing that concerns me is the overall lack of storm reports upstream to this point. There just have not been as many as you might expect, which tells me these storms are having a hard time mixing winds down to the surface. For now, the amount of shear in place coupled with the possible instability means the ceiling for this event remains somewhat high regardless if the threat materializes. Further northeast, think Knoxville metro area and points further northeast, the threat remains a little less certain. Access to better low level moisture and by extension, better instability, will be limited there. The tornado risk seems much more subdued there, with the primary threat being damaging winds. But uncertainty is a little higher there.

Behind the front, strong cold air advection will spread into the forecast area from the west. Calendar day highs may be set before daybreak tomorrow, with temperatures holding steady or possibly even falling slightly through the day. The H85 temperatures fall below zero by midday across the western parts of the CWA, and area wide by mid afternoon. Aloft, the entrance region to the departing H3 jet will be lifting north across the CWA during this time, and forecast sounding show a deep saturation layer extending through the DGZ for a few hours before moisture becomes more limited in depth. During this time, snow levels drop below 2,000 ft MSL, with surface temperatures in the valley dropping into the mid 30s. As such, expect precipitation in the higher terrain to switch over to snow by early to mid afternoon, with some decent accumulations possible in the Smokies and East Tennessee mountains before all is said and done. Even some minor accumulations in the higher terrain of the plateau and VA counties appear possible. Furthermore, snow appears likely even to the lower elevations of the valley, although the chances for any accumulations at that low of elevation are near zero.

Monday night temps drop into the 20s at low elevations area wide, with highs struggling to make it too far into the 40s on Tuesday. In general, broad upper troughing continues across the eastern CONUS through the end of the week, but gradually weakens with time. Temperatures remain near seasonal norms through Wednesday but then warm back above normal by the weekend as the influence of a strong desert southwest ridge expands eastward.

AVIATION

(12Z TAFS) Issued at 728 AM EDT Mon Mar 16 2026

Westerly winds will be gusty today with gusts up to 25 knots. Rain continues this morning but thunder is decreasing. Another round of rain will form over the region this morning, turning to light snow this afternoon as colder air moves into the region behind the cold front. A dusting up to half an inch of snow is possible at TRI. No accumulation is expected at TYS or CHA. MVFR conditions are expected this morning, improving by late afternoon or evening at TYS and CHA. TRI will be mostly MVFR through the whole period.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 48 27 45 29 / 40 0 0 0 Knoxville McGhee Tyson Airport, TN 53 24 40 25 / 60 10 0 0 Oak Ridge, TN 51 24 40 25 / 60 0 0 0 Tri Cities Airport, TN 60 22 35 20 / 100 20 10 0

MRX WATCHES/WARNINGS/ADVISORIES

NC...Wind Advisory until 8 AM EDT this morning for Cherokee-Clay.

TN...Wind Advisory until 8 AM EDT /7 AM CDT/ this morning for Anderson-Bledsoe-Bradley-Campbell-Claiborne-East Polk- Grainger-Hamblen-Hamilton-Hancock-Hawkins-Jefferson-Knox- Loudon-Marion-McMinn-Meigs-Morgan-North Sevier-Northwest Blount-Northwest Carter-Northwest Cocke-Northwest Greene- Northwest Monroe-Rhea-Roane-Scott TN-Sequatchie-Sullivan- Union-Washington TN-West Polk.

High Wind Warning until 10 AM EDT this morning for Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky Mountains-Southeast Carter-Southeast Greene-Southeast Monroe-Unicoi.

Winter Weather Advisory from 1 PM this afternoon to 2 AM EDT Tuesday for Blount Smoky Mountains-Cocke Smoky Mountains- Johnson-Sevier Smoky Mountains-Southeast Carter-Southeast Greene-Southeast Monroe-Unicoi.

VA...Wind Advisory until 8 AM EDT this morning for Lee-Russell-Scott VA-Washington VA-Wise.

Winter Weather Advisory from 1 PM this afternoon to 2 AM EDT Tuesday for Wise.