421 
FXUS64 KMRX 090542
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
142 AM EDT Mon Mar 9 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 135 AM EDT Mon Mar 9 2026

- A warming trend will continue through Wednesday with near record 
  high temperatures again.

- Chances for showers and storms return Monday night into Tuesday and
  then again by Wednesday night. Some storms could be strong to 
  severe Wednesday night, especially in western portions of the 
  area.

- Light snow is possible in the higher elevations on Thursday,
  followed by cooler and drier conditions area-wide. Then, another
  warming trend is expected through the weekend. 

&&

.DISCUSSION...
Issued at 135 AM EDT Mon Mar 9 2026

Currently, a shortwave has pushed off to our east with a stationary 
frontal boundary over the area. Recent light rainfall will continue 
to produce patchy dense fog early this morning. Through the day, 
this shortwave will lift off to the east, providing more zonal flow 
aloft and drier conditions. By this evening, a closed low will move 
into northern Mexico with its downstream upper jet approaching from 
the southwest of our area. Upper divergence in the left-exit region 
will lead to vertical ascent with the front getting pulled back 
northward. This will lead to a return of rain chances overnight and 
into Tuesday. The flow remains fairly weak overall, but MLCAPE of 
500 to 1,000 J/kg will support convection with even some potential 
for stronger storms as mid-level lapse rates are indicated reach 
near 7 C/km. In addition to the showers and storms, record heat 
comes back into view with daily records shown below: 

Daily Record High Maximum Temperatures

Date    Chattanooga    Knoxville      Tri-Cities     Oak Ridge
03-09   82(2009)       82(1925)       79(2016)       80(1974)       
03-10   81(2009)       81(2016)       82(2016)       81(2016)       
03-11   81(2006)       81(2006)       78(2006)       80(1990)  

By later on Tuesday, focus will turn towards the northwest as the 
southern jet merges with the northern jet and a deepening surface 
low progresses into the Great Lakes region for Wednesday. A strong 
LLJ and broad warm sector will be in place across much of the 
eastern U.S. ahead of its associated cold front. This will continue 
to support a broad area of potential severe weather that has been 
outlined in recent days. The latest NAM shows a likely QLCS moving 
through the region from midnight to the early morning hours with 
some others showing an earlier timing. During this time, the NAM 
struggles to show instability of more than 250 J/kg but with strong 
directional shear, including in the lower levels. 850mb winds are 
slightly weaker than some previous model runs showed, more in the 40 
to 45 kt range but still more than enough for a severe risk with 
sufficient instability. As the previous outlook showed, western 
portions of our area have the greater chance for severe convection 
due to decreasing instability. This will continue to be worth 
watching in the coming days, especially when higher resolution model 
guidance is available. But at this time, there is at least some 
threat for damaging winds or an isolated spin-up tornado. 

The front will move through the area around or before sunrise on 
Thursday, leading to a return of much colder air sufficient for a 
changeover to light snow in the higher elevations. Models certainly 
differ on how long moisture lingers into the day, but there's likely 
enough for light accumulations in the highest places. Otherwise, 
high pressure will keep the region dry to end the week. There is 
another system that will track along southern Canada Friday into the 
weekend. But, the result for our area will be a return of southerly 
flow as dry air remains in place. Temperatures will rise back above 
normal by the end of the period.

&&

.AVIATION...
(06Z TAFS)
Issued at 135 AM EDT Mon Mar 9 2026

Patchy dense fog is beginning to form over much of the area
currently, with medium to high probabilities of IFR to LIFR 
impacts early this morning across the valley. Fog will scatter 
shortly after sunrise, leading to VFR conditions. There's 
potential for a MCS cluster of TS late today to move across 
northern AL into GA, so included a PROB30 at CHA in case of a 
northern extension of that cluster. Otherwise the TAF looks rain 
free. Light winds to continue.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             79  61  79  64 /  30  70  50  10 
Knoxville McGhee Tyson Airport, TN  75  57  77  64 /  10  60  50  20 
Oak Ridge, TN                       75  57  76  63 /  10  60  50  20 
Tri Cities Airport, TN              71  48  75  57 /   0  20  40  10 

&&

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

$$

DISCUSSION...BW
AVIATION...Wellington


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