135
FXUS64 KHUN 302257
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
557 PM CDT Sat Aug 30 2025

...New AVIATION...

.NEAR TERM...
(Tonight)
Issued at 157 PM CDT Sat Aug 30 2025

High pressure remains in control of the weather across the
Tennessee Valley this afternoon, with only a few fair weather
cumulus clouds noted on satellite. These clouds will dissipate
after sunset, with another mostly clear and calm night on tap for
the Tennessee Valley. This will make another good setup for
radiational cooling in this cooler, drier air mass as temperatures
will likely drop into the upper 50s to lower 60s in most locations
by Sunday morning.

&&

.SHORT TERM...
(Sunday through Tuesday)
Issued at 1035 AM CDT Sat Aug 30 2025

Expect more of the same on Sunday as the ridge slowly shoots to
the east of the area, but still remains the dominant weather
feature across the area. With ample sunshine, highs again will
warm into the upper 80s to lower 90s in most locations with any
chances of a shower or storm remaining below 5-10%. Things will
begin to change early next week (Monday and Tuesday) as as
shortwave trough will pivot from the Ozarks into the Mid South,
pushing a front just to the north and west of the area. With
winds shifting to the south and west, Gulf moisture will gradually
creep back into the region (PWATs increasing to 1.3-1.5"). While a
bulk of the convection will be favored to the northwest (closer to
the boundary), low to medium (20-40%) for showers and storms will
return to the forecast both Monday through Tuesday. Weaker shear
will favor pulse storms to perhaps a few multicell clusters, with
locally heavy downpours and gusty winds being the main threats
with the strongest activity. The added cloud cover/rain chances
will keep highs a couple degrees lower in the low to mid 80s in
most locations.

&&

.LONG TERM...
(Tuesday through Friday)
Issued at 959 PM CDT Fri Aug 29 2025

During the fist half of the extended period, an amplifying
northern stream clipper system will dig southeastward from central
Canada into the northwestern Great Lakes, resulting in gradual
east-southeastward movement of a lower-latitude shortwave trough
across the Mid-MS Valley and into the TN Valley. Several embedded
disturbances will exist within the lower-latitude wave, and should
enhance the coverage of showers in the vicinity of a surface
convergence axis across our region at times on Tuesday/Tuesday
night. Due to widespread clouds, instability will be lower
compared to Monday and the risk for lightning/thunder is very
uncertain. However, sufficient CAPE will exist for convective
precipitation and with weak steering currents and fairly high PWAT
values, the risk for locally heavy rainfall remains apparent.
Rain should gradually end from W-to-E on Wednesday, as the
initiating shortwave trough begins to turn east-northeastward and
away from the region.

Present indications are that the northern stream clipper system
will intensify at a considerable rate on Wednesday night/Thursday,
resulting in deepening of a surface low as it tracks eastward
across the northern Great Lakes/southern Ontario. As the trailing
cold front spreads southeastward through the TN Valley on
Thursday, a second episode of showers and thunderstorms will be
possible, but the southern edge of the strongly forced convective
line may only reach as far south as northern Middle TN.
Regardless, this is something we will need to monitor over the
coming days, as mid-level westerlies increasing into the 35-45
knot range could support organized/severe thunderstorms in the
presence of sufficient moisture and lift. A cooler/drier
continental airmass will spread across the region in the wake of
the cold front, with dewpoints falling back into the u40s-l50s by
Friday.

&&

.AVIATION...
(00Z TAFS)
Issued at 557 PM CDT Sat Aug 30 2025

VFR conditions will prevail at KHSV and KMSL through the forecast
period. There is a low chance for ground fog early Sunday morning,
but coverage is not expected to be impactful.

&&

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

$$

NEAR TERM...AMP
SHORT TERM....AMP
LONG TERM....70
AVIATION...JMS