-- Discussion containing changed information from previous version are highlighted. --
017
FXUS64 KMRX 260710
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
310 AM EDT Wed Jun 26 2024

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

.SHORT TERM...
-- Changed Discussion --
(Today and tonight)
Issued at 310 AM EDT Wed Jun 26 2024

Key Message

1. Isolated to scattered showers and storms this afternoon and
evening. A couple of strong storms will be possible.

Discussion:

Continued hot today, but a brief change is coming. An 500 mb
trough will move into the TN and Ohio Valleys today, with a
surface front set to approach the region this evening. Showers and
storms will develop upstream and over the region tomorrow
afternoon. Mostly scattered coverage, with isolated strong storms
embedded and a marginal severe threat due primarily to wind gusts.
With the precip chances tomorrow and the frontal boundary`s
influence, high temps on Thursday will run roughly 7-9 degrees
cooler than today. See below.
-- End Changed Discussion --

&&

.LONG TERM...
-- Changed Discussion --
(Thursday through Tuesday)
Issued at 310 AM EDT Wed Jun 26 2024

Key Messages:

1. Isolated showers and thunderstorms possibilities through Saturday
before better chances for widespread rain on Sunday.

2. Signals pointing towards rebuilding heat early next week.

Discussion:

Tonight (the end of the short term period) and into Thursday, a
shortwave trough will be sweeping through the TN valley and southern
Appalachian region. Latest guidance forecasts this shortwave to be a
little slower than the last few days have suggested, showing it
lingering overhead Thursday morning as it and the associated surface
front move through the region. Given the slower timing,
redevelopment of showers and some thunderstorms during the day
Thursday seems likely. Drier air will build in from the northwest
and shut off rain chances later in the day. The best odds and
coverage will likely be over the higher terrain of the Appalachians.
All things considered, Thursday should be closer to normal values on
the afternoon temps side of things.

Shortwave energy shifts off the southeast coast by late Thursday
night, leaving broad, low amplitude ridging in place from Texas
eastward across the deep south through the weekend. Persistent south
to southwesterly flow in the low levels and lack of strong ridging
aloft will promote diurnally forced convection, with the highest
chances primarily over the mountains, for Friday and Saturday. A
strong disturbance will move east through the Great Lakes the latter
half of the weekend, forcing another front our direction from the
northwest on Sunday and yielding favorable chances for widespread
rainfall.

The passage of the Sunday front and Great Lakes system likely ushers
back in another hot spell however. Seems to be pretty good agreement
on showing a more pronounced upper ridge building over the lower
Mississippi River and western Tennessee valleys for the first part
of next week.
-- End Changed Discussion --

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 310 AM EDT Wed Jun 26 2024

VFR expected to prevail much of today. Chance for showers or
thunderstorms late this afternoon through tonight could produce
temporary MVFR conditions.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Chattanooga Airport, TN             99  73  90  74 /  20  40  30   0
Knoxville McGhee Tyson Airport, TN  96  72  89  71 /  20  50  40   0
Oak Ridge, TN                       96  70  88  70 /  30  60  20   0
Tri Cities Airport, TN              94  68  87  67 /  30  60  40   0
-- End Changed Discussion --

&&

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

&&

$$

SHORT TERM...GC
LONG TERM....CD
AVIATION...GC