418 
FXUS64 KMRX 111723
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
123 PM EDT Wed Mar 11 2026

...New UPDATE, DISCUSSION...

.KEY MESSAGES...
Updated at 119 PM EDT Wed Mar 11 2026

- Warm and breezy today with near record to record high
  temperatures areawide.

- Storms this evening...Storms could be strong to severe,
  especially near the Cumberland plateau. A conditional low-end
  tornado threat  will be in place.

- Cooler and drier conditions area-wide Thursday. Then, another
  warming trend is expected through the weekend.

- Another round of showers and storms will move in by late Sunday or
  Sunday night, followed by a surge of sub-freezing temperatures.

&&

.UPDATE...
Issued at 119 PM EDT Wed Mar 11 2026

Currently another warm day ahead of the approaching strong front 
moving east near the Mississippi river. Ahead of this front we're 
getting strong ridging and winds out of the south/southwest 
helping to drive temperatures well above normal. Depending on when
the front arrives we could see near record temperatures again 
today.

These warm temperatures, in addition to a strengthening LLJ along 
the front, will combine to bring a threat for strong to severe 
thunderstorms this evening to the eastern Tennessee Valley. Current 
guidance is indicating that the line of storms from the west will 
move onto the Plateau between 4-7pm and continuing through the 
evening then weakening and/or moving east of the mountains by around 
midnight EDT. Area with the best environment to see severe 
thunderstorms will be along the plateau and westward right as the 
storms are moving in this evening. CAMs are indicating we'll see a 
good amount of surface based CAPE right at the front end of the 
event if storms are able to move in a bit quicker, possibly around 
1,000+ J/kg at the peak in southeast TN. This does not last more 
than a couple of hours as the evening turns to night and we 
transition to more elevated instability, and at the same time it 
really drops off. This combined with a LLJ of 40+ knots will be the 
main driving factors behind the chance for severe thunderstorms. 
Still believe the primary threat is damaging straight line winds of 
60+ mph, primarily along the Cumberland plateau and western edge of 
the Valley while there is still daylight and before the instability 
drops off. If storms are able to maintain their strength/structure 
into the central and eastern portion of the valley the LLJ will 
still be present and the wind threat will persist. While the threat 
for tornadoes is very low, the 30 knots of 0-1km shear, low level 
CAPE being present (for a time), and LCLs around or possibly below 
1km indicate that the threat is present. Most CAMs do not indicate 
notable updraft helicity in the eastern Tennessee Valley, but the 
environment suggests that an isolated weak tornado cannot be ruled 
out... If the line of storms is able to move in faster than forecast 
the severe threat increases, but if it holds up even just a couple 
of hours slower, then the tornado threat (and overall severe threat) 
looks to decrease. Will need to be aware of the weather this evening 
for sure.

After the storms and front moves through we'll see a quick drop in 
temperatures on the backside, enough to possibly produce a brief 
window of snow, especially in the higher elevations early Thursday 
morning before sunrise. With the warm surface temperatures the past 
several days and the dry air moving in quickly behind the system, 
it's going to be hard to see any accumulations outside of the peaks 
of the mountains and ridge-lines. High temperatures will be a bit 
below normal for a change, topping out in the 50s in most valley 
locations. 

Temperatures quickly warm back up Friday and into the weekend as we 
see southerly return flow... But not for long as a deep upper trough 
and cold front move into the area on Sunday/Sunday night, bringing 
another round of widespread rain and some storms. This system may 
also bring high winds across the mountains. The severe threat 
remains low at this point but we will continue to watch. Drier and 
significantly colder air will push in behind this front for Monday 
and Tuesday, with sub-freezing temperatures area-wide Tuesday and 
Wednesday morning.

&&

.DISCUSSION...
Issued at 119 PM EDT Wed Mar 11 2026

Line of showers and thunderstorms will move through this evening,
quickly dropping flight conditions once the onset hits. Medium to
high confidence on the timing, but lower confidence on the exact
observations once it moves through. Expect rain to persist for
hours after the initial line, with lower flight categories through
most of the night.

&&

.AVIATION...
(12Z TAFS)
Issued at 718 AM EDT Wed Mar 11 2026

Brief MVFR this morning at KTRI should return to VFR in the next
two hours. Breezy conditions on tap today, with peak gusts to 25
knots, 30 knots at KTYS. Best timing estimate still holding for a
line of leading TS this evening, followed by stratiform rain
through the end of the period. Brief periods of IFR possible 
during initial TS followed by MVFR conditions during the steady 
rain. 

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             42  57  37  66 / 100  20   0   0 
Knoxville McGhee Tyson Airport, TN  39  53  34  64 / 100  30   0   0 
Oak Ridge, TN                       39  54  34  63 / 100  10   0   0 
Tri Cities Airport, TN              36  49  29  61 / 100  50   0   0 

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

DISCUSSION...99
AVIATION...99


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