695
FXUS64 KMRX 050823
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
323 AM EST Wed Feb 5 2025

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(Today and tonight)
Issued at 320 AM EST Wed Feb 5 2025

Key Messages:

1. Scattered to numerous showers with a few thunderstorms this
afternoon and tonight.

2. Gusty winds possible in the mountains Wednesday night.

.SHORT TERM...

Currently increasing clouds across the Tennessee Valley as we sit
under isentropic lift north of the front draped across the Gulf
coast states early this morning. Later today a shortwave will begin
to move through the nearly zonal flow in the atmosphere helping to
spark off shower and possibly thunderstorms in our region. The front
to our south looks to surge northward today in response to a low
moving out of the ArkLaTex region.

Convection is expected to develop across western and Middle
Tennessee this afternoon where there is expected to a more robust
LLJ helping to drive in warmer air and increased instability. As the
storms move towards the Cumberland Plateau and into the Southern
Appalachians they`ll likely become more elevated in nature and also
run into a weaker environment for convection. But there should be
enough instability that we see thunderstorms in our region with
locations near the Cumberland Plateau having the highest likelihood
of seeing lightning. Cannot completely rule out a rogue strong
thunderstorm moving out of Middle Tennessee into the Cumberland
Plateau that is capable of creating a damaging wind gust... But the
chance for widespread severe weather appears low at this time. As we
move into the overnight hours the best chances for storms shifts
further north to northeast Tennessee and southwest Virginia.

In addition to the storms the other impact from this system will be
the increased winds in the higher elevations from the low level jet
out of the southwest along with a tightening pressure gradient. It`s
borderline advisory criteria based on most probabilistic and
deterministic guidance. With a more southwest orientation the
chances for mountain wave enhanced winds appears low. So as of now
will hold off on an advisory.

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 320 AM EST Wed Feb 5 2025

1. Unseasonably warm temperatures continue into the weekend.

2. Active pattern through the next week with multiple opportunities
for rain. Some localized flooding issues will be possible especially
in Southwest Virginia which had heavy rain last week.

3. Strong wind gusts in the mountains, especially Smoky Mountains,
Saturday night into Sunday morning.

4. Seasonably average temperatures Monday and Tuesday next week.

Discussion:

In the upper levels, nearly zonal flow will be over the region the
entire forecast period. At the surface, high pressure will be
centered over the Great Plains and weak high pressure over Florida.
Low pressure centered near the Great Lakes will bring a cold front
through the Ohio Valley and Tennessee Valley Thursday and Thursday
night.

This system will bring widespread rain chances Thursday and Thursday
night. The highest rain totals will be north of I-40 where one inch
of rain is expected through Thursday night. Southwest Virginia will
see the highest rain totals which may cause flooding issues since
that area received several inches of rain last week.

Friday and through the weekend, nearly zonal flow will continue in
the upper levels. At the surface, high pressure moves in behind the
cold front Friday. Another low/frontal system will kick out of the
Rockies Saturday morning quickly moving through the Ohio Valley
Saturday evening. A cold front will move through the region Saturday
night. Again, flooding issues may be an issue given the wet soils
north of I-40, particularly Southwest Virginia. This system will be
fast moving with lower rain totals less than half an inch forecast.

Strong southerly winds Saturday evening will bring downslope wind
enhancement to the higher elevations and foothills of the East
Tennessee Mountains. A Wind Advisory will likely be needed.

The warmest days will be Thursday and Saturday with highs in the
upper 60s and lower 70s in the Tennessee Valley. It looks like the
best chance for breaking the record high will be Thursday but with
increasing clouds and rain it might be difficult. Sunday will be the
start of a cooling trend as a cold front moves through. More
seasonable temps are expected Monday and Tuesday with highs in the
upper 40s and lower 50s.

There is increasing confidence that the wet pattern will linger into
early next week as the Euro is coming into better agreement with the
GFS on a frontal boundary stalling to our south bringing rain
chances Monday and Tuesday. This could bring widespread flooding
potential across the region early next week with wet soils from
previous rains but confidence is low that far out. We will continue
to monitor this system closely.

Daily Record High Maximum Temperatures

Date    Chattanooga    Knoxville      Tri-Cities     Oak Ridge

02-06      70(2019)     73(1986)        68(1991)      70(2008)
02-07      80(2019)     77(2019)        76(2019)      76(2019)
02-08      76(1937)     75(1937)        70(2001)      71(2009)

&&

.AVIATION...
(06Z TAFS)
Issued at 1224 AM EST Wed Feb 5 2025

Clouds continue to move in from the west and should fill in much
of the area overnight. Tomorrow will see lowering ceilings ahead
of an approaching system. Isolated rain chances could impact an
airport for the last couple of hours of the TAFs, but certainty is
low due to the isolated nature of the expected storms. Storm
chances increase just beyond the end of the 24 hour TAF cycle.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             70  59  73  54 /  70  70  50  90
Knoxville McGhee Tyson Airport, TN  68  57  70  48 /  40  90  90  90
Oak Ridge, TN                       66  57  67  47 /  40  90  90  90
Tri Cities Airport, TN              59  50  66  44 /  30  80  90  80

&&

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

$$

SHORT TERM...
LONG TERM....McD
AVIATION...