Knoxville, Tennessee 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

883
FXUS64 KMRX 040529
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
129 AM EDT Mon May 4 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 126 AM EDT Mon May 4 2026

- Low chance of rain showers this morning across southwest VA and
  slight chance thunder.

- Showers and storms Tuesday night through Thursday morning, with
  periods of heavy rain possible.

&&

.DISCUSSION...
Issued at 126 AM EDT Mon May 4 2026

Ongoing showers/storms across southern IL/IN will be tracking
E-SE through the night along a weak warm front. CAMS show this
activity expanding in the next few hours, and clipping our SW VA
counties between 6-10 AM. With only weak elevated instability,
this should mainly just be showers with thunderstorms being
isolated at best. Otherwise, it will be a mostly sunny day with
temperatures warmer than we have had recently, in the mid to upper
70s.

An approaching cold front will bring showers into the area Tuesday
night, with an extended wet period expected through Thursday as that
front stalls near the area. There are several things we are watching
with this system:

Winds: A southerly LLJ jet develops Tuesday evening. REFS proability
of winds 40 kt or greater are around 70% in the East TN mountains.
With the slow progression of the front, 850 mb winds continue in
the 35-50 kt range through Wednesday.

Precip: The cold front stalls near the area on Wednesday as it
becomes parallel to the mid/upper flow. Favorable upper jet position
for QG forcing and a wide open Gulf suggest periods of heavy
rainfall, with potential for flooding. NBM precip probs for
Wednesday and Wednesday night generally show 70 to 80% probs of
seeing at least 1" or greater amounts for this event south of I-40,
with 40-60% north.

Thunderstorms: LREF joint probabilities of MUCAPE > 500 J/kg and
Bulk Shear > 40kts have dropped from previous runs, and are now
around 25% south  of I-40 (previously 40-60%). While CAPE continues
to be a limiting factor in overall severe threat, but wind shear
will be plenty. Biggest concern as of now continues to be locally
gusty winds and heavy downpours with any stronger storms.

Cooler and drier conditions can be expected for the end of the week
as a broad trough develops over the eastern Conus.

&&

.AVIATION...
(06Z TAFS)
Issued at 126 AM EDT Mon May 4 2026

VFR conditions expected for the period all sites. Light winds
early will become southwest around 10kts with a few higher gusts,
before becoming light again after sunset.


&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             80  54  79  62 /   0   0  10  50
Knoxville McGhee Tyson Airport, TN  78  54  79  61 /   0   0  10  60
Oak Ridge, TN                       79  53  77  60 /   0   0  20  70
Tri Cities Airport, TN              76  48  77  57 /  10   0  10  60

&&

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

$$

DISCUSSION...DGS
AVIATION...99