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FXUS64 KBMX 250044
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
744 PM CDT Fri May 24 2024

...New AVIATION...

.SHORT TERM...
(This evening through Saturday)
Issued at 129 PM CDT FRI MAY 24 2024

The first storms of the afternoon are currently firing across
northern portions of Central Alabama and also across eastern
Mississippi. These storms are developing along an old outflow
boundary that is moving southeastward from previous MCS activity
that occurred in Tennessee early this morning. We`ve got plenty of
instability to work with this afternoon, with 3000-3500 J/kg of
SBCAPE, 40-50 knots of effective westerly bulk shear, and steep
lapse rates aloft. LI`s are coming in between -5 and -8 along and
west of the I-65 corridor. Uncertainties currently exist in terms
of overall coverage of storms this afternoon, but it would not be
out of the question for another MCS or multiple clusters of storms
to develop and move southeast through this evening. The best
chance of this occurring would be where the severe storm has
currently developed in Monroe County, MS. With unidirectional
shear profiles, damaging straight-line winds and large hail will
be the main hazards with these storms. RAP analysis indicates the
highest amount of DCAPE across western and southwestern counties,
which could also help produce a better-defined cold pool boundary.
We`ll see how trends evolve as we go through the afternoon.

In the meantime, likely PoPs will remain in the forecast for the
northern half of the area through this afternoon, with high PoPs
continuing to the southeast before diminishing into the overnight
hours. With westerly flow aloft continuing overnight, upper level
shortwave activity will help develop additional clusters of
showers and storms across southern Arkansas and northern
Mississippi. We`ll watch those storms as they move east between
midnight and 7am, as some of those could be on the strong side
depending on how much available instability is still left from
today`s activity. PoPs have been updated to high chance
probability due to the uncertainty in placement of the storms, but
may need to be increased into the likely category before all is
said and done. Strong to isolated severe storms will remain in the
forecast Saturday afternoon through Saturday night as another
shortwave impulse moves eastward. Scattered to perhaps numerous
showers and storms are possible if enough daytime heating occurs
behind the morning activity. In terms of the CAMs, some are
showing more convective development than others, but we should
have enough support in the synoptic scale for storm development.
Hail and gusty winds will be the main hazards through Saturday,
which will be conditional based on mesoscale conditions.

56/GDG

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 229 PM CDT FRI MAY 24 2024

Model trends continue to keep MCS activity to our north on Sunday.
If outflow boundaries push into north Central Alabama and interact
with an airmass characterized by more than 1800 J/kg CAPE and bulk
shear of 35kts, a few strong to severe storms are possible. With a
slight increase in midlevel heights, it will take some focus or
boundary interaction to kick convection off. By Sunday night, a
weak front and convective line/cluster approaches the Tennessee
Valley. There`s some uncertainty on whether the line is weakening
as it moves into north Central Alabama Monday morning, as upper
level support lifts away from the area. This would leave
boundaries to interact with an unstable airmass through the day,
with scattered thunderstorms expected. If a more organized line of
storms pushes southward Monday morning, it is unlikely there will
be airmass recovery to support strong storms during the afternoon.
For now will not post threats for Monday, and wait to see how
model trends evolve.

Troughing moves to the east by Tuesday, with mid level flow
becoming northwesterly. This will allow a slightly cooler and
drier airmass to settle over the area through mid week.

14

&&

.AVIATION...
-- Changed Discussion --
(00Z TAFS)
Issued at 705 PM CDT FRI MAY 24 2024

This period has the potential of being active across Central
Alabama. A few storms were still ongoing west of MGM while
additional storms were back to the northwest. Due to anticipated sparse
coverage, nothing was mentioned at any terminal through 09z. Will
have to update if something comes closer than expected. Another
upper level feature will bring thunderstorm chances after 09z.
This feature will traverse the area from west to east through
Saturday.

Low level moisture pools near the surface on Saturday morning. It
appears ceilings will develop around 12z at IFR and gradually rise
by afternoon outside thunderstorm areas. Will hold all thunder
mention at PROB30 until the best timing can be achieved. Winds
will generally be light and variable throughout.

75
-- End Changed Discussion --

&&

.FIRE WEATHER...

Several opportunities for rain and storms through Monday, as
several impulses provide focus for convection. Enhanced coverage
is expected during the afternoon and evening, especially across
northern counties. 20 foot winds will be from the south to
southwest at less than 5 mph Saturday, increasing to 6-12mph on
Sunday. Min RH value will be near or above 45 percent through
Monday, with overnight recoveries near 100%.

&&

.PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Gadsden     66  88  67  91 /  30  60  20  20
Anniston    68  88  69  90 /  30  50  20  20
Birmingham  71  89  71  91 /  30  50  20  20
Tuscaloosa  71  91  71  92 /  30  40  10  10
Calera      70  88  71  90 /  20  50  20  10
Auburn      70  86  70  88 /  20  30  10  10
Montgomery  72  90  71  92 /  20  30  10   0
Troy        71  90  70  91 /  20  30  10   0
-- End Changed Discussion --

&&

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

$$

SHORT TERM...56/GDG
LONG TERM....14
AVIATION...75