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FXUS64 KBMX 230900
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
400 AM CDT Thu May 23 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
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(Today through Friday)
Issued at 359 AM CDT THU MAY 23 2024

Watching a MCS move ever so close to the CWA this morning. On a
whole the MCS is decaying as it slides into the drier airmass that
is on top of Central Alabama. We may get some rain in the far west
this morning but most if not all storms will dissipate before
working into the state. However, this will help to moisten the
column throughout the day and provide some outflow boundaries for
showers and storms to develop on across the west and north. The
morning update will need to see about expanding the rain chances to
the east based on those boundaries, but the high pressure will still
be in control of much of the area. Look for partly cloud skies with
passing high clouds through the day. Highs will be in the upper 80s
to low 90s, much like the past several days.

As we work into the evening the high will begin to slide to the east
a little and any shower/storm may persist and slide east. After
midnight we will begin to see rain chances increase as another MCS
begins to approach the area. Again this MCS should dissipate as it
approaches the area. It appears right now that the center will pass
to our north with the westerly flow over the area. However, it is
expected to lay out a boundary that should be the focus of showers
and storms on Friday.

So for Friday, the consensus of the models bring the remnant MCS in
the northern sections after sunrise. Most of the CAMS really pick up
the coverage after 10 AM across the north and then slide the new MCS
southward through the northern 2/3rds of the area during the day.
For the forecast will trend the forecast to the FV3 right now as
this model is the closest to the ongoing MCS. With this timing we do
have a chance at seeing strong to marginally severe storms Friday
afternoon and early evening. Right now as early as 10 AM in the
northern counties and 1 PM for the Birmingham metro, then 4 PM for
Clanton. We will need to monitor the trends for areas south of the I-
85 corridor to see if the threat continues into these areas. There
is some disagreement on the timing and intensity by the time the
storms work into this area. These times will likely change but a
good estimate for now. Of course the timing of the storms will also
greatly affect the temperatures on Friday and some refinement here
will likely be needed as confidence increases. Based on current
timing, the severe threat would be over by 10 PM. Showers and storms
will remain possible overnight as plenty of boundaries will be
around that could trigger a shower or two ahead of the next round of
storms expected.

16
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&&

.LONG TERM...
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(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
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&&

.AVIATION...
(06Z TAFS)
Issued at 1241 AM CDT THU MAY 23 2024

High pressure remains over the area with generally high clouds
through 15z. After that VFR conditions will continue, although
some low to mid-level clouds, 4 to 7 kft, will develop across the
area. Pretty much keep any measurable rain outside of TAF
locations until outside of this cycle. Winds will be out of the
south-southwest at 5 to 10 kts by late morning and through the
afternoon.

16

&&

.FIRE WEATHER...

An upper ridge over the northern Gulf of Mexico will keep most of
the rain confined to the far northern portions of Alabama through
Friday morning, with a good chance of rain across the north
through Friday night. 20 foot winds will be from the south at
less than 5 mph at night and 4-7 mph during the day. Min RH this
afternoon 40-45 percent and 45-60 percent on Friday. Max RH levels
tonight will be above 90 percent. Even better chances for rain
expected over the weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
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Gadsden     87  65  85  65 /  20  30  70  30
Anniston    88  68  87  67 /  10  20  60  30
Birmingham  89  69  88  69 /  10  20  60  30
Tuscaloosa  89  70  89  70 /  10  20  40  30
Calera      88  69  87  69 /  10  20  50  20
Auburn      87  68  87  69 /  10  10  20  20
Montgomery  90  69  90  70 /   0  10  20  20
Troy        89  67  90  70 /   0   0  20  20
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&&

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

$$

SHORT TERM...16
LONG TERM....40/Sizemore
AVIATION...16