944
FXUS64 KHUN 300345
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1045 PM CDT Mon Jun 29 2026

...New NEAR TERM, SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 1040 PM CDT Mon Jun 29 2026

 - A heat wave will occur this week with a HeatRisk value of 3
   out of 4 (Major category) to 4 out of 4 (Extreme category).
   Afternoon highs in the mid to upper 90s will be common, with
   peak heat index values between 105 to 110 degrees

 - A Heat Advisory is currently in effect through 7 PM Thursday
   for the entire Tennessee Valley.

 - Potential exists on Wednesday for a few thunderstorms capable
   of producing strong wind gusts

&&

.NEAR TERM...
(Rest of tonight and Tuesday)
Issued at 1040 PM CDT Mon Jun 29 2026

Late this evening the region remains situated under the influence
of a sub-tropical ridge centered over the TN Valley. Amid the
light wind and clear sky regime, temperatures have fallen from
today`s highs in the low/mid 90s into the upper 70s to lower 80s
as of 10 PM. However, sfc dew point temperatures largely in the
mid/upr 70s will tend to limit marked temp falls going forward
tonight. Due to the elevated temps and very humid air mass in
place, the Heat Advisory will continue through the overnight
period. Patchy fog may occur in the narrow valleys of NE Alabama
where moisture pooling can already be observed in multi-spectral
satellite imagery.

On Tuesday, the broad ridge will tend to expand while remaining
essentially in place. Thus, light winds, mostly clear sky
conditions, and a continuation of hot, oppressive conditions will
continue. Heat Index values large in the 104-110 range, along
with WBGT values around 88-90 and HeatRisk Level 3 will be
supportive for the continuation of the ongoing Heat Advisory.
There is one caveat to Tuesday however. Subtle, sheared shortwaves
will rotate southward along the eastern periphery of the ridge
and across the Srn Appalachians and into GA and eastern AL. An
area of showers/storms is anticipated to develop under the
increased forcing. The influence may be far westward to instigate
a few showers/storms mainly in NE AL. Additionally, outflows from
storms to the east could also trigger a few showers/storms.
Either way, isold development could occur, but will leave a silent
~10 POP for now.

&&

.SHORT TERM...
(Tuesday night through Thursday)
Issued at 1040 PM CDT Mon Jun 29 2026

As we progress into Wed/Thu, the ridge will tend to become more
elongated along an W-E axis, while moving gradually into the
central Appalachian region. This will result in a deeper easterly
flow developing across the region. The broad suite of global and
regional/hi-res guidance indicates a coherent shortwave will ride
south and then westward along the eastern periphery of the broad
upr ridge on Wed. This will bring the feature into the Srn
Appalachian region, further inciting vertical coupling with the
development of lower-level vorticity, and producing shower/storm
activity. The coverage of any ensuing activity is uncertain at
this time, with a rather wide range in the guidance suite.
However, given the robust state of moisture/instability expected
on Wed, strong wind gusts could occur from any stronger cells.
Steep low and mid level lapse rates, along with high mixing ratios
and very high max/min theta-e differences between low/mid levels
also suggest a potential for downbursts. The timing of this
activity remains a bit uncertain, but appears most plausible
during the afternoon. With that said, if the activity holds off
long enough on Wed, Heat Advisory criteria would still be met,
with the potential for even higher HeatRisk (widespread Level 4)
than on Tues, and heat indices perhaps reaching or breaking 110 F.


Thursday may end up being a near carbon-copy of Wed, with the
prospects for yet another vort max to move into the region near
peak heating. From an instability standpoint, the overall
parameter space may be a little less robust on Thu, but could
again be supportive of some strong updrafts/downdrafts in the
afternoon. Either way, both days will bear some watching. In
similar fashion to Wed, outside of shower/storm activity, heat may
surge once again during the day on Thursday in the moisture-rich
humid air mass. Due to uncertainty with the coverage of clouds and
showers/storms, the Heat Advisory will continue to be advertised
through Thursday.


&&

.LONG TERM...
(Thursday night through Monday)
Issued at 1040 PM CDT Mon Jun 29 2026

The apex of the upper level ridge will shift over the eastern
seaboard by Friday and also start to flatten as ripples of shortwaves
progress over the Midwest, Great Lakes, and upper Ohio Valley
regions. Some global guidance suggests that a few of these shortwaves
will dig towards the Southeast late in the weekend and into early
next week. Meanwhile, surface high pressure will persist over the
Appalachians down through the ArkLaMiss region through Sunday;
however, a cold front may approach the Tennessee Valley by early next
week, pushing the high pressure to the southeast.

Overall, expect a diurnal pattern to set up by late week, with daily
chances of showers and storms (generally 20-40%) in the afternoon
and evening. With the continued warm and humid conditions, along with
DCAPE values near or just over 1000 J/kg, we`ll be keeping an eye on
downburst potential during this time as well. By Sunday, and
especially Monday, shower and storm chances then increase as the
aforementioned cold front approaches the region. While there looks to
be more than enough instability for storms, bulk shear values are
fairly weak (10 knots or less). Therefore, severe weather is not
anticipated Sunday or Monday at this time.

As for temperatures, Friday and Saturday will continue to be very
warm with highs in the lower to upper 90s along with heat index
values in the 98-106 degree range. NWS HeatRisk looks to mainly be in
the Major category (Level 3 of 4) by late week, but WBGTs remain in
the upper 80s to around 90. Therefore, heat products may need to be
extended into the first part of the weekend to account for the
lingering heat. Make sure to take precautions for the dangerous heat!
Wear light-colored, loose-fitting clothing, stay hydrated, and take
frequent breaks in the shade if you work outside or have outdoor
activities! Look before you lock - never leave people or pets in
vehicles! By Sunday and Monday, the increased precipitation chances
will result in an ever so slight cooldown, with highs topping out in
the lower to mid 90s on Sunday and in the upper 80s to lower 90s on
Monday.

&&

.AVIATION...
(00Z TAFS)
Issued at 630 PM CDT Mon Jun 29 2026

VFR conditions expected at KHSV and KMSL TAF sites over the next
24 hours.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Heat Advisory until 7 PM CDT Thursday for ALZ001>010-016.

TN...Heat Advisory until 7 PM CDT Thursday for TNZ076-096-097.

&&

$$

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