323
FXUS64 KMRX 221002
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
602 AM EDT Thu May 22 2025

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 138 AM EDT Thu May 22 2025

Key Messages:

1. Mix of clouds and sun today. A few sprinkles possible,
especially near Chattanooga.

2. A few more sprinkles possible late tonight into Friday morning.

Discussion:

We`re in a longwave pattern defined with troughing across the
Eastern CONUS and subtle shortwaves diving southeast through our
area today and tonight. Dry air and subsidence near the surface
will limit any precipitation chances, but a few sprinkles will be
possible. Overall, we`re expected a mix of clouds and sun with
temperatures slightly below normal with the troughing in place
across the region.

A stronger shortwave tonight will bring a reinforcing shot of cold
air to the region for Friday with chances of upslope light rain
showers and sprinkles (especially to northeast Tennessee and
southwest Virginia). Any precipitation accumulation would be
little to none except for potentially across the highest
elevations of the mountains where light rainfall accumulation
would be possible.

&&

.LONG TERM...
(Friday through Thursday)
Issued at 138 AM EDT Thu May 22 2025

Key Messages:

1. Light sprinkles possible Saturday, but mostly dry with mix of
clouds and sun.

2. Rain chances increase on Sunday into early next week as a low
pressure system approaches the region.

3. Continued light rain showers or sprinkles possible behind the
low pressure system towards the mid to late part of next week with
much cooler than average temperatures.

Discussion:

Ridging begins to build back across the region from the west with
isentropic lift aloft increasing clouds and the potential of some
light rain showers or sprinkles, especially south of Interstate
40, on Saturday. Most areas are forecast to remain dry with any
accumulating precipitation being very light.

Isentropic lift along a stationary or warm frontal boundary across
the Tennessee Valley will increase on Sunday afternoon and night
with increasing area-wide rain chances. Most of this rain is
forecast to be light.

By Monday, the area of low pressure is forecast to move eastward
with upper-level troughing becoming more amplified across the
region behind the cold front. 1 to 2 inches of rainfall are
expected area-wide with localized higher spots. At this time, no
major impacts are expected. However, it will bear watching on how
this system evolves and it`s exact track. If we do receive more
convection and it trains over the same spots, we could have some
localized flooding issues early next week.

By mid-week, the upper-level wave pattern becomes very amplified
with anomalous troughing across the Southern Appalachians. This
will result in cooler weather with sporadic light showers
possible, mainly with a diurnal trend in coverage that peaks in
the afternoon peak heating hours. CPC continues to highlight the
Tennessee Valley having a higher probability of cooler than normal
temperatures for much of the next 8 to 14 days.

&&

.AVIATION...
(12Z TAFS)
Issued at 601 AM EDT Thu May 22 2025

VFR conditions prevail today. A few sprinkles or virga will be
possible this morning at CHA and this evening at TRI, but no
accumulating precipitation is expected. Westerly winds remain
gusty at TYS and TRI this afternoon with decreasing winds after
sunset this evening.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             78  56  77  53 /  10  20   0  10
Knoxville McGhee Tyson Airport, TN  74  53  72  49 /  10  10   0  10
Oak Ridge, TN                       74  52  72  48 /   0  10   0  10
Tri Cities Airport, TN              70  47  67  43 /  10  10   0   0

&&

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

$$

SHORT TERM...JB
LONG TERM....JB
AVIATION...JB