835
FXUS64 KBMX 232351
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
651 PM CDT Thu May 23 2024

...New AVIATION...

.SHORT TERM...
(This afternoon through Friday)
Issued at 1257 PM CDT THU MAY 23 2024

A weakening cluster of convection associated with a weak impulse in
the mid-level flow over Mississippi will move into the northwestern
portions of the area within the next couple of hours. This activity
has been slowly decreasing in intensity as it moves into a drier,
less unstable environment. As such, not expecting to see much rain
east of I-65. Ridging over the Gulf of Mexico is suppressing rain
chances for much of the Gulf Coast region and producing zonal flow
aloft. Mild conditions are expected tonight with lows in the mid
60s to lower 70s.

Another weak shortwave tomorrow could produce additional chances for
scattered thunderstorms, mainly during the afternoon, but the weakly
forced environment and erratic behavior of the MCS activity that is
favored in this pattern makes for a low confidence forecast. While
the environment is not extreme, low-level moisture is progged to
increase tomorrow. ~2000-2500 J/kg of MUCAPE would support the
potential for some strong to severe thunderstorms during the late
morning through the afternoon as temperatures warm into the mid to
upper 80s, so will maintain the Marginal severe risk as is for now,
but there isn`t much model continuity on the degree of development
we could actually see in terms of the areal coverage. For now,
will take more of an ensemble approach with HREF mean QPF
indicating potential for scattered to numerous storms across the
northern half of Central Alabama, highly dependent on how
convection evolves upstream over the Mid-South and Tennessee
Valley regions.

86/Martin

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 240 PM CDT THU MAY 23 2024

Long term forecast is on track this afternoon, with an active
pattern carrying us through the holiday weekend. Forecast for
Friday night and Saturday is highly dependent on the evolution of
thunderstorms to our north, and could see storm chances increasing
Friday evening as timing and track of a MCS changes. Airmass on
Saturday remains unstable and supportive of thunderstorms, but
activity will depend on airmass recovery and boundaries left from
activity Friday night. For now, will maintain a marginal risk of
storms Saturday afternoon and evening. Another wave of storms is
expected in the Monday-Monday night timeframe, as a weak cold
front moves southward into the area.

14

Previous long-term discussion:
(Friday night through next Wednesday)
Issued at 359 AM CDT THU MAY 23 2024

Despite the presence of a broad deep-layer ridge across the region
on Saturday, we`ll also have a moist, unstable boundary layer with
potential boundaries which will contribute to a low-end severe
weather threat. MLCAPE of 2,000-3,000 J/kg and 30-40 kts eff. bulk
shear will support a few strong/severe storms should forcing
overcome the progged height rises during the afternoon. Vertical
wind profiles suggest east-southeast moving supercells are possible
should the right scenario evolve, but also depict weak storm-
relative inflow. For now it appears, if a boundary establishes,
it`ll be of a northwest to southeast orientation. Damaging wind
gusts and large hail will be possible if a few strong updrafts can
get going during the afternoon. Additional wind threats could
materialize once clustering/cold pool aggregation occurs. Convection
will wane in the evening with focus for a more widespread severe
outbreak establishing to our northwest on Sunday. In fact, Sunday
will be dry/hot overall, with heat indices in the mid 90s during the
afternoon. However, we`ll need to watch for MCS potential as a cold
front moves toward the Tennessee Valley Sunday night into Monday
morning.

There`s some uncertainty regarding the exact timing of the
aforementioned cold front. Regardless, after frontal passage on
Monday, Tuesday through Thursday looks more stable with cooler,
drier air across our region.

40/Sizemore

&&

.AVIATION...
(00Z TAFS)
Issued at 645 PM CDT THU MAY 23 2024

A few shortwave troughs move through the zonal flow aloft during
the period. The best moisture will be north and therefore that is
where the pops will be mentioned. A few showers and thunderstorms
may approach the northern terminals on Friday after 15z and have
PROB30 mention at this time. Otherwise, VFR conditions expected
most of the time at most locations. TOI may experience a brief
period around sunrise of some MVFR ceilings and vis. This
restriction should be short-lived and dissipate quickly with
heating. Winds become light and variable overnight and south
5-10kts on Friday.

75

&&

.FIRE WEATHER...

Several opportunities for rain and storms through the weekend, as
several impulses provide focus for convection, with enhanced
coverage during the afternoon and evening, especially across
northern counties. 20 foot winds will be from the south to
southwest at less than 10 mph through Sunday. Min RH value will be
above 40 percent through Sunday, with max RH levels overnight
above 90 percent.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     67  83  65  88 /  30  60  40  40
Anniston    68  86  67  88 /  20  50  30  40
Birmingham  70  86  69  88 /  20  50  30  40
Tuscaloosa  70  88  71  90 /  20  40  30  30
Calera      70  87  70  89 /  20  40  30  30
Auburn      69  86  70  88 /  10  20  20  20
Montgomery  69  89  71  90 /  10  20  10  20
Troy        67  89  70  90 /  10  20  10  20

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...86/Martin
LONG TERM....14
AVIATION...75