Heat in Alabama, July 9, 2024

Area Forecast Discussion
National Weather Service Huntsville AL
1035 AM CDT Tue Jul 9 2024

...New NEAR TERM...

.NEAR TERM...
(Rest of Today)
Issued at 1035 AM CDT Tue Jul 9 2024

A very warm and moist environment remains in place across the
Tennessee Valley late this morning as evidence by dewpoints in the
mid to upper 70s and temperatures in the mid to upper 80s. There
is still plenty of cloud cover in place, but a breezy southerly
wind around 10 MPH and ample heating that will occur during breaks
in the clouds will warm temperatures into the low to mid 90s
across much of the region by the afternoon. As such, this will
place peak heat index values near or in excess of 105 degrees in
many locations. Thus, we've issued a Heat Advisory for the entire
Tennessee Valley through 00z this evening.

A weak front/convergence boundary extending southward from the
remnants of "Beryl" has currently triggered a broken line of
showers across eastern Mississippi. This activity will gradually
shift NE into northwest and north central Alabama through the
early to mid afternoon. While SBCAPE is plentiful (up to
2000-2500 J/kg), lapse rates remain poor, 0-1 SRH remains below
100 m2/s2, and effective shear is capped around 25-30 kts. For
this reason, think any potential for strong to marginally severe
storms will be very low. In fact, we may struggle to realize any
lightning with this activity. Still localized shear vectors from
the passing remnants of "Beryl" to our north could help to
organize a few weak cells, especially across far northwest
Alabama. As such, a brief localized potential for damaging winds
and, yes, even a brief spin-up. Again, we feel the probability of
this is very-low, but it is not zero. Main window for any
showers/storms will be from 16z-22z. Should the coverage of
convection outperform, heat indices will likely remain below
Advisory criteria.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 358 AM CDT Tue Jul 9 2024

Scattered showers or thunderstorms could linger into the early
evening hours, before shifting northeast of the area, as the
center of tropical depression Beryl moves into the central Great
Lakes area. Much drier air being advection into the southwestern
portion of the depression should put an end to precipitation
chances around midnight in northern Alabama and southern middle
Tennessee.

As tropical Depression Beryl becomes non-tropical and moves
into southeastern Canada, significantly drier and somewhat cooler
air is advected into the southeast. This should make for a nice
day on Wednesday. Highs should remain in the 85 to 90 degree range
primarily with dewpoints dropping into the mid 60s in the afternoon.
Scattered clouds should linger over the area early in the morning
before becoming mostly clear.

As an area of low pressure (formerly tropical Depression Beryl)
is forecast by most guidance to move further northeast Wednesday
night into Thursday, an upper level ridge begins to redevelop over
the southeastern CONUS. This should start building heat over the
area again on Thursday. Highs in the lower 90s look reasonable
then. Not expected much cloud cover either on Thursday.

&&

.LONG TERM...
(Friday through Monday)
Issued at 358 AM CDT Tue Jul 9 2024

This upper level ridging builds over the area over the weekend.
Little cloud cover is shown then and into early next week. Little
cloud cover is expected. This should allow high temperatures to
climb into the mid to upper 90s at least. Luckily dewpoints
should be much lower (lower to mid 60s -- maybe even a few upper
50s). With such high temperatures expected, we will have to watch
this period closely for the issuance of any heat related
advisories.

Low chances of showers or thunderstorms could return early next
week. However, these look unorganized and not very strong.

&&

.AVIATION...
(12Z TAFS)
Issued at 552 AM CDT Tue Jul 9 2024

Not much change from previous thinking. VFR conditions will likely
be in place through 16Z at both terminals. Then expect -SHRA and a
lower cloud deck to develop over both terminals. A tempo group was
kept in between 17Z and 21Z at KMSL and between 18Z and 22Z at
KHSV. MVFR CIGS or VSBYS could occur during that period. Winds
around 15 knots gusting to 25 knots are expected. A low chance was
of -TSRA was keep in the forecast with a PROB30 group during the
early evening hours. Winds should become more westerly and
decrease to between 5 and 10 knots after 06Z. MVFR CIGS are
expected to develop as well.

&&

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

NEAR TERM...AMP.24
SHORT TERM....KTW
LONG TERM....KTW
AVIATION...KTW