663
FXUS64 KHUN 251141
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
641 AM CDT Fri Jul 25 2025

...New AVIATION...

.NEAR TERM...
(Today)
Issued at 407 AM CDT Fri Jul 25 2025

Deep-layer southeasterly flow continues to become established
across the local forecast area this morning, as our region is
currently situated between a subtropical high along the
southeastern Atlantic Coast and a broad/unorganized mid-level
trough (featuring a couple of embedded vorticity maxima) lifting
slowly northwestward from the central Gulf. Within this regime,
low stratus clouds have recently developed and will continue to
spread northward through the early morning hours, and this along
with a light SSE breeze will keep temps in the mid 70s through
sunrise. Although dewpoints depressions have begun to contract in
a few locations, the risk for fog development appears rather low.

After sunrise, showers and thunderstorms (initially confined to
the northwest and north-central Gulf Coast) will begin to expand
northward within the moistening and diurnally destabilizing
airmass across the Gulf Coast states. This activity is likely to
develop as far northward as northern portions of MS/AL by this
afternoon (warranting higher POPs compared to yesterday), and
although a few cells may begin to develop as early as 14-16Z, we
will reserve our highest rain chances (30-40%) for the 18-00Z
timeframe. With moistening profiles aloft contributing to PWAT
values in the 2-2.2" range, lightning and heavy downpours will be
the most significant impacts from the stronger storms, as weaker
lapse rates should yield CAPE generally in the 1500-2500 J/kg
range.

Highs will be impacted a bit by the coverage of morning clouds
and afternoon showers/thunderstorms, with most locations only
reaching the u80s-l90s. Although heat indices will be just shy of
Heat Advisory criteria (105 degrees), it will still be hot and
proper precautions should be taken for those outside. Make sure to
drink plenty of water, take frequent breaks in the shade, wear
light-colored and light-weight clothing, and never leave people or
pets in vehicles!

&&

.SHORT TERM...
(Friday Night through Sunday Night)
Issued at 1010 PM CDT Thu Jul 24 2025

Another night of lows in the lower to mid 70s with patchy valley
fog is on deck for Friday night. Little to no showers/storms are
anticipated as well.

The aforementioned upper ridge will gradually shift westward
through early next week. Although, a series of shortwaves look to
progress over the Midwest and Ohio Valleys on Saturday before the
ridge fully strengthens over the Southeast late this weekend into
early next week. Surface high pressure will largely persist over
the Appalachians as well, but extend southward over the
northeastern Gulf coast. Overall, expecting gradually hotter
conditions with decreasing shower/storm chances through the
weekend.

The main concern will be the heat, as highs increase from the
lower 90s for most locations on Saturday to the lower to mid 90s
on Sunday with lows in the lower to mid 70s both nights. Heat
indices are expected to reach between 102-109 degrees Saturday
afternoon and between 105-110 degrees on Sunday. A Heat Advisory
will likely be needed to account for these conditions this
weekend. As stated above, please remember heat safety! Yes, it`s
hot during the summer, but we are entering the hottest heat wave
of the summer so far (especially by early next week - more on this
below). Please take the heat seriously! Make sure to drink plenty
of water, take frequent breaks in the shade, wear light-colored
and light-weight clothing, and never leave people or pets in
vehicles!

&&

.LONG TERM...
(Monday through Thursday)
Issued at 1010 PM CDT Thu Jul 24 2025

The long term period is dictated by oppressive heat as an upper
level ridge and subsequent sfc high pressure system remain
stagnant over the southeast U.S. High temperatures throughout this
time are forecast to reach the mid to upper 90s coupled with heat
indices up to 105-110 degrees (potentially exceeding 110 degrees
on Tuesday and Wednesday). Overnight lows will provide little to
no relief as they drop into the mid to upper 70s. These
temperatures are around 5-10 degrees above normal throughout the
area for this time of year. HeatRisk is forecast to reach major
(risk level 3 of 4) throughout all of the Tennessee Valley, with
isolated portions reaching extreme (risk level 4 of 4) by mid
week. This means this level of heat will likely affect anyone
without cooling/hydration as well as health systems and
industries. In isolated areas, this could also affect some
infrastructure by mid week. Heat products will be very likely in
the week through at least Wednesday. We continue to encourage
everyone to stay hydrated, take breaks in shaded areas if working
outdoors, and wear light-colored, lightweight clothing.

In addition to the heat threat, a series of upper level
shortwaves will allow enough forcing for low chances (30% or less)
of showers and thunderstorms daily. We will also be monitoring
the evolution of an upper level trough swinging eastward through
the Great Lakes region by mid week, which could bring slightly
increased storm coverage through the area by the end of the work
week.

&&

.AVIATION...
(12Z TAFS)
Issued at 641 AM CDT Fri Jul 25 2025

There have been no significant changes to previous aviation
forecast reasoning, as current satellite data/sfc observations
suggest that patches of MVFR-level stratus will continue to spread
northward this morning within a deep SE flow regime. The stratus
layer will begin to lift/scatter btwn 14-16Z, with diurnal
destabilization supporting the development of sct SHRA/TSRA during
the aftn hours (some of which could impact the terminals btwn
21-2Z). Partial clearing is anticipated later this evening, and
with redevelopment of low stratus clouds early Sat morning
uncertain at this point, we have not included additional MVFR cigs
in the current forecast. Sfc flow will generally range from SSE-
SSW with sustained speeds of 5-10 kts.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...None.
TN...None.

&&

$$

NEAR TERM...70/DD
SHORT TERM...26
LONG TERM...HC
AVIATION...70/DD