-- Discussion containing changed information from previous version are highlighted. --
000
FXUS64 KMRX 151647 AAA
AFDMRX

Area Forecast Discussion...UPDATED
National Weather Service Morristown TN
1247 PM EDT Mon Apr 15 2024

...New AVIATION...

.UPDATE...
Issued at 1046 AM EDT Mon Apr 15 2024

Overall, the forecast is on track, but a few minor adjustments
will be made to PoP/Wx grids this evening. The 12Z OHX sounding
shows an elevated mixed layer above a strong capping inversion.
The cap is unlikely to be broken in our area this afternoon with
the lack of forcing and the surface front well to our north, but
there is the potential of convection that forms over KY/WV to
track SE into our SW VA and NE TN counties. Forecast soundings
show a weaker cap in northern sections. Coverge should be
scattered at best, though a few strong storms are possible if they
arrive early enough before sunset. Timing for potential storms
appears to be in the 00-06Z time frame, so instability will be
waning as storms approach. Some hail and gusty winds cannot be
ruled out.

&&

.SHORT TERM...
(Today and tonight)
Issued at 213 AM EDT Mon Apr 15 2024

Key Messages:

1. Warm temperatures continue through today and tonight.

2. Chance of thunderstorms north of I-81 late this afternoon and
evening.

Discussion:

In the upper levels, a ridge will be over the region today and
tonight. At the surface, high pressure is over the Southeast. A
cold front is stalling over Kentucky and West Virginia today. This
boundary will bring showers and thunderstorms to SW Virginia and
NE Tennessee late this afternoon and evening. Gusty winds and
small hail will be possible with the strongest storms with good
instability this afternoon. Elsewhere will be dry.

Today will be warmer than normal with highs getting into the 80s
for most of the Tennessee Valley which is about 10 degrees above
normal. The 850mb jet that elevated winds for us the past few days
will subside early this morning. WAA will continue with
southwesterly flow but winds will be much lighter than yesterday
with gusts up to 15 or 20 mph likely the highest for this
afternoon.

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 213 AM EDT Mon Apr 15 2024

Key Messages:

1. Increasing rain chances with showers and thunderstorms Wednesday.
A break in the rain now Thursday. Rain chances and more storms
Friday and Friday night.

2. Turning cooler Saturday and Sunday behind front. Lingering rain
chances for the weekend.

Discussion:

Tuesday will likely end up being the warmest day of the forecast as
the strong ridge combines with southerly flow in the lower levels
that will increase moisture and warm advection into the region. All
of this will occur ahead of an approaching low pressure system that
will push through a cold front during the middle of the week.
Showers and thunderstorms could begin on Wednesday ahead of the main
front, but models are still in disagreement with how widespread
storm activity will be on this day. Storms that are able to form
should be able to tap into moderate instability and shear late in
the afternoon and evening, so a few strong thunderstorms will be
possible on Wednesday.

Front should be east of the Appalachian Mountains by Thursday
morning, but with the clearer skies even behind the front
temperatures won`t change too dramatically.

Another weaker front looks to move in quickly behind the mid week
front which will bring another round of showers and thunderstorms to
the region. Most notably with this secondary front will be the much
cooler temperatures behind it as we head into the weekend. Daytime
high temperatures are expected to drop 15 or more degrees between
Friday and Sunday afternoons.

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1243 PM EDT Mon Apr 15 2024

VFR conditions, winds of 8-12 kt, and scattered clouds around 5
kft are expected through the rest of the day. This evening,
showers and thunderstorms are possible in SW VA and NE TN, with a
potential for a few to be near TRI. Most likely time frame is
00-06Z, but confidence is low of one at the terminal, so will
continue to mention as a PROB30. If there is rain at the terminal,
fog could develop late in the night. Tomorrow will have scattered
to broken cloud cover with light winds.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             86  61  83  64 /   0   0   0  20
Knoxville McGhee Tyson Airport, TN  83  61  84  65 /   0  10   0  10
Oak Ridge, TN                       85  60  83  64 /   0   0   0  10
Tri Cities Airport, TN              80  58  80  60 /  20  20  20   0

&&

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

$$

SHORT TERM...DGS
AVIATION...DGS