501
FXUS64 KHUN 140210
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
910 PM CDT Tue Aug 13 2024

...New NEAR TERM...

.NEAR TERM...
(Tonight)
Issued at 910 PM CDT Tue Aug 13 2024

No major changes to the near term forecast this evening. We
continue to watch the deterioration of an MCS over southern
Missouri and northeast Arkansas. Scattered shower activity
associated with this feature will likely continue to the southeast
and move into northwest Alabama very late tonight into early
tomorrow morning. Any rainfall will be very light. Additional
cloud cover and influx of moisture over northwest Alabama will
moderate low temps overnight with areas west of I-65 seeing lows
in the upper 60s to low 70s with areas east of I-65 dropping into
the low to mid 60s.

&&

.SHORT TERM...
(Wednesday through Thursday Night)
Issued at 227 PM CDT Tue Aug 13 2024

Subtle changes to our forecast coming for Wednesday and Thursday
as the center of a mid/upper ridge pivots into the ArkLaTex
region, placing the Tennessee Valley under more pronounced NW flow
aloft. Another MCS will form tonight across the central Plains
and Ozarks and likely be approaching the Mid-Mississippi Valley by
12z. Hi-Res guidance is now hinting that additional showers and a
few thunderstorms will form along a remnant outflow boundary over
western Tennessee and northern Mississippi -- eventually drift SE
toward portions of northern and central Alabama during the
morning through the early to mid-afternoon.

Little modification to the relatively drier and more stable air
mass will have taken place overnight. Thus, the intensity of any
convection that does form upstream should be diminishing as it
moves into our area. However, a glance at model soundings do
suggest some limited moisture with a little SBCAPE that would
support a general thunderstorm or two. Have capped PoPs at 20-30%
given the uncertainties about how widespread showers/storms will
be in our area on Wednesday, but will need to continue to watch
mesoscale and environmental trends this evening and overnight.

The mid/upper ridge will amplify ever so slightly to the east on
Thursday, which may serve to suppress convection across our area
for the most part. Model soundings indicate a drier profile than
Wednesday, but do hint at a modest amount of SBCAPE developing by
the afternoon during peak heating in the low to mid 90s. A
lingering outflow boundary could serve as a focus for a few
showers or storms during the afternoon and for this reason felt
low chance (20%) PoPs were warranted.

&&

.LONG TERM...
(Friday through Monday)
Issued at 142 AM CDT Tue Aug 13 2024

An upper shortwave trough is slated to progress from the Midwest
down into the Ohio and Tennessee valleys from Friday through early
Sunday morning. At the surface, a cold front looks to approach the
region from the northwest on Friday, then traverse the area sometime
Saturday evening or overnight. High pressure is then shown to build
into the Tennessee Valley early next week. This pattern will lead to
medium (40-50%) chances of showers and storms on Friday, with low to
medium (30-40%) chances on Saturday. Sufficient bulk shear and
instability may lead to at least some stronger storms ahead of the
front on Friday. Additionally, bulk shear values increase Saturday
afternoon and evening. Overall, confidence on severe weather for
Friday and/or Saturday is low at this time, but we`ll keep an eye on
these trends with subsequent updates. Low chances of lingering
showers and storms then comprise Sunday, with drier weather returning
early next week.

Temperatures will be warm to start, but will overall follow a
downward trend through the long term. Highs in the lower to mid 90s
are anticipated Friday and Saturday, with lows in the upper 60s to
lower 70s Friday night. The hottest day of the long term forecast
looks to be Friday, with heat indices potentially reaching Heat
Advisory criteria over portions of far northwestern Alabama. Most
of our local area is highlighted in a moderate risk of heat-
related illness from the NWS HeatRisk tool, with some spots over
northwest and north- central Alabama in a major risk. Will
continue to monitor in case a Heat Advisory becomes necessary;
but, in the meantime, please remember heat safety. Stay hydrated,
wear light-colored, loose- fitting clothes, and take frequent
breaks in the shade. Temperatures then begin to decrease a bit
after cold FROPA Saturday evening/night. Highs in the upper 80s to
lower 90s are expected Sunday and Monday, with lows in the mid to
upper 60s for most locations by Monday night. It`ll also be less
muggy by Monday, with dew points dropping into the 60s (versus dew
points in the lower 70s like on Friday).

&&

.AVIATION...
(00Z TAFS)
Issued at 730 PM CDT Tue Aug 13 2024

VFR conditions prevail through the period. Afternoon cumulus field
continues to deteriorate leaving primarily SCT-BKN mid and high
clouds at or above 9k feet. An area of showers will progress into
northwest Alabama early Wednesday morning and have included VCSH
at KMSL between 14/14z-14/20z as confidence in coverage remains
low. SCT clouds at 4k-7k feet will accompany this activity,
decreasing in coverage late in the period. Winds remain light at
8 knots or less.

&&

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

$$

NEAR TERM...KG
SHORT TERM....AMP
LONG TERM....26
AVIATION...KG