861
FXUS64 KHUN 171902
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
202 PM CDT Thu Jul 17 2025

...New NEAR TERM...

.NEAR TERM...
(Tonight)
Issued at 202 PM CDT Thu Jul 17 2025

Thus far, just few to scattered cumulus has developed today with
deeper moisture and showers and thunderstorms remaining across the
southern half or so of AL. A band of more enhanced cumulus south
of Smith Lake and DeKalb County may manage to pop a few showers or
a thunderstorm or two yet this afternoon and early evening, so
won`t rule it out yet. Otherwise, no changes are necessary to the
previous forecast for today into tonight.

Previous Discussion...
For today, low to medium chances (10-30%) of showers and storms
are anticipated. When viewing model guidance of storm activity
this afternoon/evening, we look to be between potentially strong
to severe storms to our north moving from Missouri over Kentucky
as well as broken shower/storm bands from the tropical low
pressure system moving over the northern Gulf coast to our south.
While bulk shear is minimal for our local area, instability will
be abundant (generally reaching between 2000-3000 J/kg later this
afternoon). Thus, while no organized severe weather is forecast,
we`ll be monitoring the potential for gusty winds, frequent
lightning, as well as heavy downpours which could lead to
flooding. Model PWAT values range between 1.65 inches to over 2
inches this afternoon and, compared with BMX Sounding Climatology,
is mostly within the 75th-95th percentile range (1.86-2.00 inch
PWATs). Therefore, showers/storms will be efficient rainfall
producers and we`ll need to keep an eye on any heavy showers and
training storms (especially over NW AL where a decent amount of
rain fell last evening).

In addition to the shower/storm chances, it will be hot today.
Highs are forecast to top out in the lower to mid 90s for most
locations. This, along with elevated moisture, will result in heat
indices in the 102-109 degree range generally along and west of
I-65. These are the locations where a Heat Advisory remains in
effect through 7PM this evening. Make sure to take necessary
precautions if you head outside: drink plenty of water, take
frequent breaks in the shade, and never leave people or pets in
vehicles!

Shower and storm activity is expected to gradually diminish
through mid to late evening with the sunset and loss of daytime
heating. Little to no shower/storms is anticipated after midnight.
Patchy fog may be possible, especially for areas that receive
rainfall today. Lows later tonight are then expected to only drop
into the lower to mid 70s.

&&

.SHORT TERM...
(Friday through Saturday)
Issued at 1102 AM CDT Thu Jul 17 2025

Mainly zonal flow will persist aloft through the first part of
the weekend, with a few shortwave ripples that will traverse the
upper Mississippi River Valley through the Ohio and Tennessee
valleys. The aforementioned tropical low is expected to continue
to move to the west and gradually dissipate through the weekend.
Meanwhile, surface high pressure will remain planted over the
Appalachians to our east/northeast. South to southwest flow will
therefore be common over our area, which will help maintain
elevated moisture through the weekend.

Thus, daily medium to high (40-60%) chances of showers and storms
are forecast through Saturday, with activity expected to
gradually decrease through the evening hours and little to none
overnight. Ample instability but low shear continue to be shown by
guidance. Much like the last few days, this will result in no
organized severe storms but the potential for a few stronger
storms capable of producing gusty winds, frequent lightning, and
heavy rainfall. The Weather Prediction Center has the Tennessee
Valley outlooked in a Marginal Risk of excessive rainfall due to
the persistent elevated moisture and likelihood of showers/storms
being efficient rainfall producers. Remember, when thunder roars,
go indoors! Turn around, don`t drown if you encounter flooded
roads!

With the higher probability of precipitation both Friday and
Saturday, high temperatures will likely be dampened a little bit.
Forecast highs therefore range in the upper 80s to lower 90s
across the local area both days. Although Heat Advisory criteria
is not expected to be met, summer is not over yet - it will still
be hot! Remember heat safety if you have outdoor plans! Lows will
then continue to be in the lower to mid 70s.

&&

.LONG TERM...
(Saturday night through Wednesday)
Issued at 1018 PM CDT Wed Jul 16 2025

A broad area of high pressure will will gradually begin to become
established over the Deep South early next week. However, with
ample moisture underneath this ridge, low to medium (30-60%)
chances for showers and storms will remain in the forecast each
day. As we trend toward mid to late week, this ridge will amplify
and become more established over the region. Confidence is
increasing that another heatwave will begin to develop late in the
period as highs in the mid 90s will be common (with some upper 90s
more likely in northwest Alabama) by Wednesday. Combined with
higher dewpoints, heat indices near above 105 degrees may become
more probable. Thus, additional heat products may be needed during
this timeframe.

&&

.AVIATION...
(18Z TAFS)
Issued at 1206 PM CDT Thu Jul 17 2025

Low chances (10-20%) of showers/storms are forecast at the
terminals this afternoon. Did not include this in the TAFs for
now, as confidence is low in exactly where storms will form and if
they`d impact the TAF sites. Any activity should dwindle through
the evening, with little to none overnight. A low chance of patchy
fog is possible late tonight, especially for areas that receive
rainfall today. The bigger concern will be the potential for low
ceilings, as guidance suggests MVFR to IFR CIGs later tonight.
This will then lift through Friday morning, with VFR conditions
returning by mid-morning. The better chances for showers/storms
then comes Friday afternoon (30-60%), but this is outside of the
forecast period to be included in the TAFs. Outside of any storms,
southerly winds around 5-10 knots this afternoon will decrease to
be light this evening. Southerly winds around 5-10 knots are then
anticipated again by tomorrow afternoon.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Heat Advisory until 7 PM CDT this evening for ALZ001>007-016.

TN...Heat Advisory until 7 PM CDT this evening for TNZ076-096.

&&

$$

NEAR TERM...17/26
SHORT TERM....26
LONG TERM....AMP
AVIATION...26