143
FXUS64 KMRX 131855
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
255 PM EDT Fri Mar 13 2026
...New DISCUSSION...
.KEY MESSAGES...
Updated at 254 PM EDT Fri Mar 13 2026
- Dry and breezy conditions are expected today with slightly warmer
temperatures on Saturday.
- A dynamic system will impact the area later on Sunday through
Monday. First, strong winds are expected with a high-end mountain
wave event likely Sunday night. Then, showers and isolated storms
will move through the area into Sunday morning, bringing potential
damaging winds.
- Rain will change to snow Monday with accumulations possible in
the higher elevations. Then, dry and cool conditions will
continue through the week.
&&
.DISCUSSION...
Issued at 254 PM EDT Fri Mar 13 2026
Currently, a trough and upper jet are centered well to our north
with a surface low moving across the Great Lakes region. High
pressure to our south will help keep the area dry with southerly
flow increasing through the rest of the day. With a decent MSLP
gradient and 850mb winds exceeding 30 kts, wind gusts of 30 mph or
more will be common. It's certainly possible for some locations to
gust close to 40 mph but most places likely staying just below
advisory criteria. By Saturday, the northern system will have pushed
off well to our northeast with increasing high pressure keeping the
region dry. As the MSLP gradient and 850mb flow weaken
significantly, winds will be much more limited than today. Height
rises will also continue the recent warming trend.
Saturday night into Sunday morning, focus will turn towards the
northwest as troughing deepens over the Rockies due to stronger
upstream flow over the Pacific Northwest. This will lead to a
deepening surface low that tracks towards the Great Lakes around
990mb. This will produce a strong, broad warm sector and 850mb jet
in excess of 50 kts. This will lead to breezy conditions through the
day on Sunday as these winds increase to over 40 kts out ahead. By
Sunday evening and Sunday night, the increasing focus will be
mountain waves, given the strong MSLP gradient and 850mb jet
exceeding 50 kts. At this time, watch/warning criteria looks likely,
assuming no large change in trends. Additionally, the other concern
is the threat for severe weather ahead of the frontal boundary.
Based on the late night / early morning timing for our area,
instability will be very limited. However, the impressive strength
of the 850mb and overall system certainly raises concern for wind
damage, even if instability is very limited. Behind the front, a
strong push of cold air is expected, which will lead to a transition
of rain to west to east on Monday. With this timeframe being later
in the month, accumulations will likely be limited to the higher
elevations and possibly northeastern areas. 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. This will
still be worth watching in the coming days. Afterwards, high
pressure will move into the area, leading to a return of drier
weather. Temperatures will remain below normal due to continued
troughing through the week.
&&
.AVIATION...
(18Z TAFS)
Issued at 131 PM EDT Fri Mar 13 2026
VFR conditions prevail. Main focus for aviation impacts will be
gusty south to southwesterly winds continuing this afternoon.
Strong winds will wane this evening and remain light for the
remainder of the TAF period as sfc high pressure builds in.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 42 75 54 74 / 0 0 0 20
Knoxville McGhee Tyson Airport, TN 42 71 49 74 / 0 0 0 10
Oak Ridge, TN 40 70 48 74 / 0 0 0 10
Tri Cities Airport, TN 37 67 46 69 / 0 0 0 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...BW
AVIATION...KRS
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