088
FXUS64 KHUN 091052
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
552 AM CDT Sun Aug 9 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 1242 AM CDT Sun Aug 9 2026

 - Daily chances of thunderstorms are expected through the week.
   The primary hazards will be gusty winds, heavy downpours, and
   frequent lightning but there is potential for isolated severe
   downbursts and hail as well.

 - High heat index and HeatRisk values may necessitate heat
   products next week.

&&

.NEAR TERM...
(Today)
Issued at 333 AM CDT Sun Aug 9 2026

We`re keeping an eye on low stratus and fog development early
this morning. While the cloud deck building over portions of
Tennessee and into Alabama around midnight seemed to suggest the
potential for lower ceilings this morning, clouds have actually
begun to clear over the past hour versus increase. Therefore, fog
will likely be the main concern through the morning, especially
for river valleys and locations that received rainfall yesterday.
This can be seen in the Nighttime Microphysics Satellite imagery
presently. Additionally, reductions in visibilities have been
reported by surface stations over NE AL as well as in Muscle
Shoals and Huntsville over the past hour. Confidence is low
whether this will become widespread and dense, but we`ll continue
to monitor trends and observations in case a Dense Fog Advisory
becomes necessary for all or portions of the local area this
morning. If you encounter fog while traveling this morning, make
sure to use low beam headlights and keep ample space between you
and the vehicle in front of you. All fog will then lift and
dissipate through mid-morning, with shower and storm chances
becoming the main focus yet again through this evening.

As the previous shift mentioned, there seems to be some
discrepancies in the Hi-Res guidance so far this morning with
regards to the coverage of showers and storms this afternoon and
evening. Some models indicate lower coverage while others suggest
similar coverage to Saturday. This may be because the global
models hint that the upper trough looks to weaken/lift north
through the day as upper high pressure over the Atlantic builds
farther west over the Southeast. This will be monitored, but at
this time, maintained low to medium chances (20-50%) of showers
and storms for today. Some guidance also suggests that the higher
probability of shower/storm activity may be east of I-65. Our
highest PoP forecast reflects this potential. We`ll continue to
monitor and provide updates through the day, but heavy downpours
(leading to localized flooding) and frequent lightning will be the
main threats with any storms that do form. If any stronger storms
are able to develop, there is the continued potential for gusty
winds and hail as well. Stay weather aware today!

Currently, high temperatures are slated to reach the upper 80s to
around 90 degrees. If the coverage of showers and storms today is
lower, warmer temperatures may be realized, perhaps by a few
degrees. With an already warm and muggy day on tap (heat index
values mainly between 96-103 degrees and Moderate HeatRisk [level
2 of 4]), this scenario would lead to greater heat concerns.
Regardless, please remember heat safety! Take plenty of breaks in
the shade if you work outside or have outdoor activities. Also,
drink plenty of water and never leave people or pets in vehicles!

&&

.SHORT TERM...
(Tonight through Tuesday)
Issued at 1100 PM CDT Sat Aug 8 2026

The long wave pattern begins to take a slight tilt with ridge
reinforcement in the Southwest CONUS and troughing along the East
Coast. This will result in a similar tilting of the stalled upr
trough across the TN/OH Valley region, while this feature becomes
increasingly sheared and less defined. Nevertheless, while the
remnants of the feature remain essentially in place for Monday,
and part of Tuesday, the weak dynamics will still help to act as a
focusing mechanism for shower/storm development. This may tend to
favor eastern areas in closer proximity to the better forcing and
aligned with the higher instability/moisture axis (but also
elevated heating from the plateau). Thus POPs will be higher
generally in the east both days. With the region still ensconced
in the warm/humid air mass, all heat-related data suggest Heat
Advisories could be needed early next week.

&&

.LONG TERM...
(Tuesday night through Saturday)
Issued at 1100 PM CDT Sat Aug 8 2026

By Tuesday night, NW flow aloft develops over the eastern CONUS. A
longwave trough axis settles ESE via upper flow into Missouri and
Kentucky with a weaker trough axis hinted at that extends from the
eastern Ohio Valley SW into NW GA and NE AL. This forcing could
produce a low to medium chance of showers of thunderstorms just after
daybreak on Wednesday that increases in coverage as the main
longwave trough axis digs southeast during the afternoon and
evening hours. This will likely keep highs a tad lower in the mid
80s to around 90 degrees. Shear remains weak as this occurs, so
organized severe weather is not expected. SBCAPE could be between
2000 and 4000 J/KG though in the afternoon for storms to tap into.
With high PWATS continuing, heavy rainfall will continue to be a
threat with stronger storms that may develop. DCAPE values are
around or over 1000 J/KG and soundings do hint at dry air aloft
for storms to tap into, so some stronger downbursts look possible
with this convection. Models differ on how long this convection
lasts into the evening hours before dissipating, but would expect
by 10 PM this would occur (some guidance holds on to activity
until just after midnight). Not sure how much clearing we will see
based on model soundings into the daybreak hours on Thursday.
This lack of clearing despite light winds should keep fog from
developing.

Models differ concerning how quickly the upper ridge builds
northward Thursday afternoon and evening. Some keep a weak longwave
trough axis in place over southern Alabama NW into Missouri. This
solution would keep the area in a wetter pattern with a higher
chance of showers/storms part of the day on Thursday. The other
solution pushes the longwave trough axis well east of the Atlantic
coast. This solution would mean drier and hotter weather on
Thursday with a low chance of showers/storms in the forecast.

Model guidance does seem to converge on a solution that by Friday
morning the upper ridge to our south does strengthen and shift
northeast over the area. This should warm things up some more.
Disturbances moving through NW flow well to our north should keep
at least a low chance of showers and storms in the forecast over
NE Alabama and southern middle Tennessee. Unfortunately, with this
strengthening of the upper ridge, 925 mb temperatures in most of
the guidance climb into a 25 to 28 degree range (GFS 28 to 29
degree range). This would lend itself with good insolation to
highs climbing back into the 95 to 100 degree range unfortunately.
With surface winds originating from the Gulf of Mexico, dewpoints
will likely remain high. This may begin another mini-heat wave
period over the area, where Heat products may be needed.

Models diverge a bit on how much further north the upper ridge
builds over the weekend and how much cloud cover/scattered
convection occurs. Which scenario holds true could have somewhat
of a limiting effect on high temperatures and the heat. Either
way, it will remain very hot and the heat wave could continue
through the weekend.

&&

.AVIATION...
(12Z TAFS)
Issued at 552 AM CDT Sun Aug 9 2026

Much of the cloud cover from earlier in the night that hinted
that lower CIGs would occur have mostly dissipated; although,
there are some clouds that are streaming over north Alabama at
present. The main concern has been fog, which has become dense at
times over NE AL. Both terminals have seen reductions in VIS over
the past few hours due to fog, but observations have bounced
around a bit between MVFR and IFR conditions. Expecting this to
continue over the next couple of hours, so we have included a
TEMPO group to help account for this at both terminals. Any fog
will then lift and dissipate through mid-morning. As has been the
case the past couple of days, low to medium chances (20-60%) of
showers and storms this afternoon/evening will bring the potential
for heavy rain, frequent lightning, and gusty winds as well as
lower VIS and CIGs. Confidence in the exact timing and location of
these storms remains low. Shower and storm activity is then
expected to diminish through this evening with tranquil conditions
by late evening. Although, we`ll need to watch the potential for
fog development that could result in VIS reductions at the TAF
sites again late tonight.

&&

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

$$

NEAR TERM...26
SHORT TERM....KDW
LONG TERM....KTW
AVIATION...26