Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS64 KMRX 021844

Area Forecast Discussion
National Weather Service Morristown TN
244 PM EDT Mon Oct 2 2023


(This evening through Tuesday)
Issued at 242 PM EDT Mon Oct 2 2023

Key Message:

Another quiet weather day today and tomorrow with some patchy fog
possible overnight.


Persistence forecast is the name of the game again today with the
Omega blocking pattern overhead leading to above normal temperatures
and generally calm weather. Some small baby cumulus clouds present
again this afternoon with the enhanced heating going on, and these
small shadows will be the only relief from the temperatures in the
80s across most of the Valley. Generally calm atmosphere is expected
with some occasional breeze up to 5-10 mph this afternoon. Quiet
weather will  continue into the overnight hours with another round
of patchy fog likely to develop in the river valleys near sunrise.
Another warm day can be expected tomorrow with temperatures likely
to be within a few degrees of what we experience today.


(Tuesday night through next Monday)
Issued at 242 PM EDT Mon Oct 2 2023

Key Messages:

1. Dry weather and warm temperatures will continue to dominate
through the majority of the work week, exacerbating rapid onset
drought conditions.

2. Precipitation chances return Friday, with only light accumulation
totals expected.

3. Cooler temperatures arrive for the weekend.


A large high pressure system over the Atlantic coastal region will
continue to dominate the weather pattern through Wednesday, so above
normal temperatures and dry conditions will persist.

A pattern change ensues on Thursday as a closed low tracks across
the northern Plains and south-central Canada. A piece of shortwave
energy splits off from this system and drops southeast, amplifying
the trough across the Great Lakes and OH Valley. An associated cold
front approaches our area Thursday night, with a line of showers
moving into our area on Friday. The question with this system is how
much moisture will be available for measurable precip, as the
Gulf never opens up ahead of the front for a deep moisture feed.
Given the trough amplification and jet streak position, lift
should be adequate for at least scattered showers. The forecast
will have high chance PoPs north, closer to this better forcing,
to slight chance PoPs south. With the models having some timing
differences, will continue some low/slight chance PoPs into
Saturday morning in eastern sections.

With the deep trough (or closed low, depending on the model) over
the eastern Conus, much cooler temperatures will build into the area
behind the cold front. High temperatures over the weekend will be
mainly in the 60s, with overnight lows in the 40s and some 30s in a
few northern locations.


(18Z TAFS)
Issued at 1247 PM EDT Mon Oct 2 2023

Light winds and mostly clear skies are expected for the next 24
hours. Fog will be possible at KTRI right around sunrise, but will
wait to see what the dew point depressions are after sunset before
biting off on the more pessimistic guidance.


Chattanooga Airport, TN             61  86  61  86 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  58  86  58  86 /   0   0   0   0
Oak Ridge, TN                       59  86  58  86 /   0   0   0   0
Tri Cities Airport, TN              55  83  57  83 /   0   0   0   0




AVIATION... is the U.S. government's official web portal to all federal, state and local government web resources and services.