365
FXUS64 KBMX 161107
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
607 AM CDT Fri Aug 16 2024

...New AVIATION...

.SHORT TERM...
(Today through Saturday)
Issued at 257 AM CDT FRI AUG 16 2024

Currently watching the expected MCS slide through Missouri and
into Tennessee. By sunrise the activity should begin to dissipate in
intensity and overall coverage. However, the outflow boundary will
continue and likely be in our north by late morning. This will
likely be a trigger for showers and storms this afternoon into the
evening hours. While the activity will generally be more scattered
in nature, with the added focus of the larger outflow boundary, we
will include a marginal threat for severe storms from 2 PM through
10 PM this evening across the the northern third of the area. While
hail cannot be ruled out, damaging winds will be the primary concern
for this event. We will also need to monitor for the potential of
another MCS overnight into Saturday morning. At this time it appears
that the bulk of the activity will stay north of much of the area
through daybreak Saturday with the model consensus a little slower
in the progression.

With the current forecast and consensus of models, the same outlook
for today can be expected on Saturday, but a touch slower and a bit
further south. The activity will once again be more scattered in
nature, but overall coverage quite high. We have backed off of
the threat across the southeast, but went a row of counties south
of guidance to account for the model consensus. The time for
Saturday will be from 3 PM to 11 PM for the northern 2/3rds of the
area. While hail cannot be ruled out, damaging winds will be the
primary concern for this event.

16

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 257 AM CDT FRI AUG 16 2024

Key messages:

- A somewhat conditional risk of severe storms with damaging winds
continues Sunday afternoon and evening, depending on how storms
evolve Saturday/Saturday night.

- One more day of heat indices at or above 105 degrees appears
likely on Sunday, before a less humid and not as hot air mass moves
in for much of next week.

A highly amplified pattern for mid to late August will persist
through the long term period, with strong subtropical ridging
remaining centered over the High Plains flanked by a trough/upper
low off the coast of the Pacific Northwest and an amplifying trough
over the eastern CONUS. Showers and storms will probably be ongoing
Saturday evening, some of which may be strong to severe. Some
ensemble members bring down some additional storms from the north
late Saturday night into Sunday morning though the majority of
members are dry. Another shortwave in northwest flow aloft down the
back side of the trough moves in Sunday as the cold front moves into
the area. The environment will be conditionally favorable for severe
storms on Sunday as 0-6km bulk shear strengthens to an unseasonably
strong 30-40 kts and mid-level lapse rates begin to steepen, with
plenty of dry air aloft/DCAPE. Severe storm potential will be
dependent on any outflow boundaries from Saturday night`s convection
and how much moisture gets scoured out/if the mid-level dry air is
too dry to sustain updrafts. Convergence will be limited along the
front as winds veer to the northwest ahead of the front due to lee
troughing. But there is enough signal for convective initiation in
the latest guidance to message a marginal risk of severe storms.
Mesoscale trends will continue to be monitored as we get closer in
case any increase in storm coverage/risk level becomes apparent. A
heat advisory will probably also be needed for at least some of the
southern counties.

Behind the front, a drier and "cooler" air mass for late August will
move in with highs in the upper 80s to lower 90s and lows well into
the 60s a couple nights with low humidity. Late in the period the
main trough lifts out but a weakness will get left behind. Depending
on how quickly this weakness retrogrades some moisture may begin to
return by the end of the period. As high pressure pushes eastward
and weak wedging develops, easterly winds will keep the heat at bay.

32/Davis

&&

.AVIATION...
(12Z TAFS)
Issued at 607 AM CDT FRI AUG 16 2024

VFR conditions will continue through the forecast period with
mostly clear skies and variable or calm winds this morning. After
15z clouds will begin to develop across the northern half of the
area, with SHRA/TSRA development expected across the northern
half of Central Alabama after 18z, more likely by 21z. Continued
the PROB30 for TSRA through 2 and 3z at all terminals except for
MGM. Did add in VCSH at MGM after 3z. Will most likely begin the
TEMPO TSRA with the 18z TAFS as the bulk of models keep TSRA out
until 21z.

16

&&

.FIRE WEATHER...

A couple rounds of showers and storms will move through this
afternoon through Sunday afternoon, with the highest chances
across the north. RH values will drop below 40 percent in far
southeastern portions of Central Alabama this afternoon, but
otherwise remain above 40 percent through the weekend. A dry air
mass returns next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     94  71  95  69 /  60  60  60  50
Anniston    94  73  92  70 /  30  60  60  50
Birmingham  94  74  95  72 /  60  60  60  50
Tuscaloosa  96  74  94  73 /  50  50  60  40
Calera      94  75  92  73 /  30  40  60  50
Auburn      93  73  92  72 /  20  20  40  40
Montgomery  96  74  96  73 /  20  20  40  40
Troy        95  72  95  72 /  10  20  30  40

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 10 AM this morning to 9 PM CDT this evening
for the following counties: Bibb-Blount-Dallas-Fayette-Greene-
Hale-Jefferson-Lamar-Marengo-Marion-Perry-Pickens-Shelby-Sumter-
Tuscaloosa-Walker-Winston.

&&

$$

SHORT TERM...16
LONG TERM....32
AVIATION...16