162 
FXUS64 KMRX 141855
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
255 PM EDT Sat Mar 14 2026

...New DISCUSSION...

.KEY MESSAGES...
Updated at 253 PM EDT Sat Mar 14 2026

-  A strong system will impact the region Sunday into Monday.
   First, a strong mountain wave event is likely Sunday and 
   Sunday night, with breezy winds in valley locations Sunday 
   afternoon and night as well.

-  A line of showers and storms will move through the region
   between 1AM and 8AM EDT Monday. The main threat will be
   damaging winds, but a few spin-ups cannot be ruled out, 
   especially in the southern valley and plateau. 

-  Very cold air filters in Monday through Wednesday morning. Snow
   showers may bring light accumulations in higher elevations and
   parts of southwest VA Monday afternoon and night. 

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

&&

.DISCUSSION...
Issued at 253 PM EDT Sat Mar 14 2026

We are currently situated under a weak upper ridge across the 
southeast CONUS with surface high pressure centered over the 
southeastern Great Lakes region. This will continue to translate to 
slightly above normal temperatures through Sunday evening. Throughout 
Sunday a very amplified system is expected to develop across the 
central CONUS, gradually working towards the lower Mississippi River 
Valley and Tennessee Valley by Sunday evening. The primary impacts 
from this system are categorized below.

Non-convective winds:  

During this time frame, a persistent southerly low-level jet is 
expected from the Tennessee Valley into the Ohio Valley. Combined 
with a strong pressure gradient and a favorable inversion around 750-
700mb, a strong mountain wave wind event is expected. Based on 
latest HREF probabilities the start of advisory level winds have 
trended earlier in time. With the upgrade from a High Wind Watch to 
a Warning the timing has also been moved up to 06Z Sunday and now 
set to end 14Z Monday. 

Additionally, gusty winds are expected across valley locations as 
the pressure gradient strengthens along with afternoon mixing. Most 
places will gust in the 30s, with maybe some isolated locations near 
40(northern plateau). The better chance to see more frequent gusts 
near advisory criteria will be just ahead of or behind the front (0 
to 12Z Mon). Given this period is still ~36 hours out and more 
borderline, will hold off on an advisory at this time but one may 
need to be considered with tonight's forecast package. 

Convective Hazards:

Not too much change in potential hazards as the main axis of 
convection swings through between 2 and 8 AM EDT Monday. The main 
change has been an eastward expansion of the slight risk as 
confidence continues to increase in potential impacts.

The primary focus will be on damaging winds with the heavy 
precipitation aiding in the transportation of winds aloft to the 
surface. 12Z HRRR and NAMBufr soundings are in pretty good agreement 
that a brief period of surface CAPE between 200-500J/kg will exist in 
the first few hours of onset for most locations along and west of I-
75, especially southern valley and southern plateau. The shear 
profile will also be very strong... 0-1km shear near 40 kts with 
effective shear near 50 kts. For this reason, a tornado threat also 
exists but the most likely location will be in that southern valley 
and plateau area where there will be better surface instability, 0-
3km CAPE near 40kts, and streamwise vorticity to aid in 
tornadogenesis. The afternoon convective outlook update did adjust 
this region to a 5% tor threat. 

Cold and light snow post frontal passage:

With this amplified system, very strong cold air advection is 
expected post frontal passage Monday morning. Temperatures will 
likely be falling throughout the day rather than a typical diurnal 
trend. Periods of snow showers are expected Monday morning into 
Monday night. Light accumulations will be limited to high elevations 
and perhaps a very short lived dusting on some valley floors, but 
the very warm temperatures for many days in advance of the system 
will help to limit accum. Climatologically, snowfall of 0.5 inches 
or greater has not occurred this late in the year in Knoxville since 
1999. However, this has happened several times in the Tri-Cities and 
other higher elevation areas. Temperatures will approach record lows 
on Tuesday morning, and potentially Wednesday morning in some 
northern spots. Sub-zero wind chills are also likely in the 
mountains Monday night/Tuesday morning. A gradual warming trend 
among dry conditions expected late week. 

&&

.AVIATION...
(18Z TAFS)
Issued at 147 PM EDT Sat Mar 14 2026

VFR under high pressure conditions can be expected through early
tonight. A LLJ is forecast to increase overnight and may allow for
the hazard of LLWS at all TAF sites between 04-14z or so. Into the
day Sunday, winds will mix down to the SFC with SE to Sly winds
and gusts. Gusts between 25 and 30KT are possible.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             53  73  37  48 /   0  10 100  40 
Knoxville McGhee Tyson Airport, TN  50  73  38  50 /   0  10  90  70 
Oak Ridge, TN                       50  72  36  48 /   0  10  90  60 
Tri Cities Airport, TN              47  69  40  58 /   0  10  80  90 

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...High Wind Warning from 2 AM Sunday to 10 AM EDT Monday for 
     Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier 
     Smoky Mountains-Southeast Carter-Southeast Greene-Southeast 
     Monroe-Unicoi.

     High Wind Watch from Monday morning through Monday afternoon for 
     Blount Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier 
     Smoky Mountains-Southeast Carter-Southeast Greene-Southeast 
     Monroe-Unicoi.

VA...NONE.
&&

$$

DISCUSSION...KRS
AVIATION...KS


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