070
FXUS64 KHUN 142311
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
611 PM CDT Mon Jul 14 2025

...New AVIATION...

.NEAR TERM...
(Rest of Today and Tonight)
Issued at 329 PM CDT Mon Jul 14 2025

There have been no significant changes to near term forecast
reasoning since the update earlier this morning. Although coverage
of showers and thunderstorms (thus far today) has been confined
to the higher terrain of northeast AL/southern TN, current radar
data suggests that additional updrafts are beginning to mature
within an axis of subtle low-level streamline confluence extending
from western TN southeastward into east-central AL. Cells with
high reflectivity cores reaching up to 18-20 kft will begin to
produce lightning, and this along with brief outflow wind gusts
(up to 40-50 MPH) will be the main concerns as the convection
spreads slowly eastward before dissipating by 1-2Z. After early
evening precipitation dissipates, mostly clear skies and calm
winds may result in development of mist/fog (primarily in
locations that receive rainfall) as temps fall into the l-m 70s.

Previous Discussion:
In the mid/upper-levels, a ridge of high pressure will remain
centered across the southern Gulf Coast states throughout the near
term period. A weak shortwave trough (initially across
southeastern OK) will lift slowly northeastward around the
periphery of the ridge and into the western Ozark Plateau by 12Z
Tuesday, as an easterly wave undercuts the 500-mb high and
retrogrades slowly westward-southwestward across the southern FL
Peninsula. At the surface, our forecast area will remain under the
influence of high pressure with light/variable environmental flow
expected to continue through the period.

In the absence of synoptic scale forcing for ascent, current
thinking is that thunderstorms will continue to develop later this
morning, initially across the higher terrain of northeast
AL/southern TN, with redevelopment in this same region throughout
the afternoon. A broader coverage of thunderstorms is anticipated
to our west (focused across the Mid-South region), where lift
related to the shortwave trough will have more of an impact on the
synoptic environment, and convective outflow propagating eastward
from this activity may generate new cells across the western
portion of the forecast area later this afternoon. As temperatures
warm into the l-m 90s, dewpoints in the l-m 70s will contribute
to CAPE in the 2000-2500 J/kg range (perhaps locally higher in a
few areas), and this along with DCAPE in the 500-1000 J/kg range
suggest that the most intense cells will be capable of producing
strong downburst winds of 40-50 MPH in addition to frequent
lightning and locally heavy rainfall (with PWAT values in the
1.8-1.9" range). In locations that do not experience impacts from
convection, heat indices will be uncomfortably high and in the
98-105F range.

In similar fashion to yesterday, lingering afternoon showers and
thunderstorms across our region will quickly dissipate by 1-2Z,
with the greatest coverage of nocturnal convection expected to
occur along and downstream from the shortwave trough. Mostly clear
skies and calm winds will support development of patchy fog in
locations that experience rainfall this afternoon/evening, and
lows will be in the l-m 70s.

&&

.SHORT TERM...
(Tuesday through Wednesday night)
Issued at 1118 AM CDT Mon Jul 14 2025

Latest model data suggests that the mid-level ridge in place
across the Gulf Coast states will continue to lie across our CWFA
throughout the short term period but will assume a more zonal
orientation with time as it begins to phase with a stronger
subtropical high retrograding across the western North Atlantic.
This will reduce impacts from both the shortwave trough (traveling
along the northern edge of the ridge) and easterly wave
(traveling along the southern edge of the ridge) for our region,
with showers and thunderstorms largely tied to subtle zones of
low-level convergence. Although a few afternoon showers and
thunderstorms will be possible once again tomorrow, storm coverage
will be higher to our east, where a surface trough/confluence
axis related to the easterly wave will focus development of
convection from the central FL Panhandle north-northeastward into
western portions of VA/NC. Some of this activity may eventually
spread into portions of northeast AL Tuesday evening before
dissipating, and we have included a slightly higher POP in this
region to account for this scenario.

Chances for showers and thunderstorms will increase region-wide
on Wednesday (and continuing into Wednesday night) as the surface
trough shifts westward into the TN Valley. As far as storm impacts
are concerned, similar thermodynamic parameters will exist on
both Tuesday and Wednesday (compared to today), with a few
instances of gusty outflow winds expected to accompany cells
producing frequent lightning and locally heavy rainfall. Afternoon
highs will remain in the l-m 90s, with heat indices of 98-105F
(perhaps a few degrees higher in normally warmer urban locations),
with overnight lows in the l-m 70s.

&&

.LONG TERM...
(Thursday through Sunday)
Issued at 800 PM CDT Sun Jul 13 2025

The models forecast the track of the Gulf Trough/low into the
lower MS valley from Thursday into Friday, while a weak west- east
ridge axis remains at 5h from OK through the TN valley. This will
keep a similar weather forecast late this week into next weekend.
By next weekend, MCS (ridge riders) may trickle into KY and TN as
well. So expect more diurnally driven convection, along with
watching potential outflow boundaries from any MCS that does
approach our area from the north/northwest. High temperatures will
remain very persistent in the upper 80s to lower 90s, with lows
mainly in the lower 70s during this period.

&&

.AVIATION...
(00Z TAFS)
Issued at 611 PM CDT Mon Jul 14 2025

VFR conditions will be the predominant flight category at each
terminal through the period with light winds and a mostly clear
sky. Very low chances for showers and storms will exist Tuesday
afternoon, but probabilities are too low to warrant a mention at
this time.

&&

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

$$

NEAR TERM...70
SHORT TERM....70
LONG TERM....17
AVIATION...AMP.24