686
FXUS64 KOHX 181103
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
603 AM CDT Mon Aug 18 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 600 AM CDT Mon Aug 18 2025

- Heat Advisory much of the area through Tuesday with highs in
  the mid to upper 90s and heat indices in the triple digits west
  of the Cumberland Plateau. Cooler air will move in for late
  week.

- Low rain chances through Tuesday, then chances for scattered
  showers and storms increase Wednesday.

&&

.SHORT TERM...
(Tonight through Tuesday Night)
Issued at 1059 PM CDT Sun Aug 17 2025

s of 10 pm CDT...skies across Middle Tennessee are mostly clear.
Temperatures have dipped into the upper 70s across most the area,
with the low 80s reported in the Nashville Metro and the low 70s
along the Cumberland Plateau. With dewpoints still in the low 70s,
it remains quite muggy. Winds were light and variable. At the
surface, a broad area of high pressure remains across the eastern
United States. Aloft, the persistent upper level ridge of high
pressure over the Southern Plains seemed to be intensifying, and
this is also something seen in the model guidance...not a great sign
for the upcoming heat anticipated Monday and Tuesday.

For tonight, benign weather is anticipated as we`ve lost daytime
instability and there are not any shortwaves/disturbances heading
our way. There could be some fog overnight tonight, mainly the
patchy variety in parts of the plateau, especially those locales
that saw one of the few thunderstorms during the daytime Sunday.

On Monday, as mentioned above, the upper level ridge of high
pressure is expected to intensify and expand to the east, stretching
all the way from the Southern Plains to the Atlantic Coast. This
should lead to temperatures being comparable to, if not a degree or
two warmer, Sunday`s high temperatures. Further, with the
strengthening of the high pressure, most model guidance indicates
near zero chance for afternoon thunderstorms. Therefore, it doesn`t
seem as though we`ll escape another oppressive hot summer day with
some clouds or an afternoon storm. Glancing at some of the
probabilistic data, we have about a 20% chance of reaching the
triple digits in the Nashville Metro tomorrow. However, we did reach
98 on Sunday so it`s not out of the question we reach the century
mark. At this point, see no reason to make significant adjustments to
the current heat advisory and will let it ride.

On Tuesday, another oppressively hot day is very likely. Once again,
some of our forecast guidance wants to boost surface highs another
degree or two. One point of optimism is that it looks like our
afternoon dewpoint temperatures should drop into the upper 60s,
which would keep our heat index forecast about the same despite
being slightly warmer. In addition, there does seem to be an upper
level trough that wants to move south on the eastern periphery of
the upper level high, and this could bring some isolated
thunderstorms into the area. However, this would most likely occur
Tuesday afternoon, so we`ll have to endure the full brunt of the
heat before getting any relief. Severe weather would not be
anticipated due to the low wind shear preventing a more organized
convective threat. At this point, see no reason to make significant
adjustments to the current heat advisory and will let it ride.

&&

.LONG TERM...
(Wednesday through next Monday)
Issued at 1059 PM CDT Sun Aug 17 2025

For this long-term forecast, the big news is we finally begin to
turn the tide on the heat wave here in Middle Tennessee. In
addition, a cold front should push through by this weekend, bringing
cooler temperatures (in the 80s for daytime highs) by Sunday into
next week.

On Wednesday, the upper level ridge finally decides to relent and
pivot to the west, taking it`s full wrath with it. It will still be
hot on Wednesday, don`t get me wrong. However, compared to how we`ll
start the week, Wednesday shouldn`t be as oppressive. Further, there
will be a weak cold front moving south towards Middle Tennessee.
This, paired with a shortwave trough sagging south across the Ohio
Valley, should provide enough forcing for shower and thunderstorm
activity during the afternoon and evening. Current forecast projects
chances for precipitation in the 30 to 40 percent range, though it
wouldn`t surprise me if we creeped a little higher along our
Kentucky border where daytime heating/instability and incoming front
coincide. While no severe weather is anticipated, it wouldn`t
surprise me if we had to issue a few flood products (flood
advisories, perhaps a flash flood warning) as a result of high
precipitable water along the front and slow storm movement.

For Thursday through Saturday, daytime thunderstorm chances should
continue, mainly focused along the Cumberland Plateau. However, with
Middle TN being in an uncertain upper level pattern between three
different systems (a building trough over the Great Lakes, the high
pressure ridge over the western United States, and Hurricane Erin
off the Atlantic Coast), it`s tough to say honestly what the storm
chances will look like each day. Overall, just like recent days, the
thunderstorm chances may bring a few of us some relief during an
afternoon, while most of us miss out and the recent drought
conditions continue to worsen. Afternoon high temperatures each day
should be in the upper 80s to low 90s.

On Sunday into Monday, we`ll FINALLY get the real relief were
looking for. What are we talking about here? How about high
temperatures in the 80s...with dewpoints in the 50s. Wow, this is
going to feel wonderful after the heat wave. This change is
something that the Climate Prediction Center has been highlighting
now for several days, and the models are fairly consistent with this
upper level trough building over the Great Lakes, which would force
our cold front south through the Ohio Valley and eventually the
Tennessee Valley. Hold on just a little longer for that relief from
the heat!

&&

.AVIATION...
(12Z TAFS)
Issued at 600 AM CDT Mon Aug 18 2025

Patchy fog this morning resulting in MVFR conditions along the
Plateau will diminish around 14Z. VFR conditions prevail
thereafter with northeasterly winds less than 10 knots. Low chance
for patchy fog developing again after 06Z which could bring MVFR
visibilities to CSV and SRB.

&&

.PRELIMINARY POINT TEMPS/POPS...
Nashville      98  74  98  74 /   0   0  10  10
Clarksville    98  73  98  73 /   0   0  10  20
Crossville     89  67  90  67 /   0   0  10  10
Columbia       98  73  98  73 /   0   0  10  10
Cookeville     91  69  92  70 /   0   0  10  10
Jamestown      90  67  90  68 /   0   0  10  10
Lawrenceburg   95  71  96  71 /   0   0  10  10
Murfreesboro   97  72  98  72 /   0   0  10  10
Waverly        98  73  98  72 /   0   0  10  20

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT Tuesday for TNZ005>009-023>030-
056>062-075-093>095.

&&

$$

SHORT TERM...Husted
LONG TERM....Husted
AVIATION.....Clements