964
FXUS64 KBMX 261816
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
116 PM CDT Wed Jun 26 2024

...New SHORT TERM, AVIATION...

.SHORT TERM...
(This afternoon through Thursday)
Issued at 111 PM CDT WED JUN 26 2024

Contrary to much of the 12Z guidance, a large coverage of showers
and thunderstorms have already developed across much of central
and eastern Mississippi and into western portions of central
Alabama. Once the cu field began developing this morning, it
didn`t take long for rain to start falling. This activity is being
driven by a large increase in moisture associated with an
approaching trough axis and cold front over the Midsouth region.
There`s currently a moisture gradient over the area, and there`s
still some drier air across the eastern half where dewpoints have
once again mixed down into the lower to mid 60s. However, moisture
will advect eastward with propagation of the trough, so expect
further area-wide development of convection through the afternoon
with the highest chance for rain focused generally along and west
of I-65. This rain should give us some relief from the heat, but
not soon enough as most areas have already reached the mid to
upper 90s. Per RAP mesoanalysis, MUCAPE is around 3000-4000 J/kg
in our west where dewpoints are in the lower 70s. While shear
values are rather weak, some strong downbursts may produce
damaging winds, and storms could also produce torrential downpours
with PWATs around 2".

There`s been an increasing signal of scattered showers and storms
continuing overnight and into tomorrow as the cold front and strong
PVA move southward into the area. Some hi-res models are even
resolving an MVC-like feature over the area early tomorrow morning
which would further support additional rain and thunderstorms. So
luckily, the odds at receiving beneficial rain seem to be improving
for the next 24 hours. The scattered to numerous showers and
cloudy skies will keep temperatures in the 80s tomorrow.

86/Martin

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 346 AM CDT WED JUN 26 2024

Key message:

- Hot and increasingly humid conditions are expected this weekend
  into next week, with heat indices at or above 105 degrees at
  times, especially Sunday. Scattered showers and storms will
  also be possible each afternoon.

Subtropical ridging will continue to build eastward into northern
Alabama Friday, while a weakness in the ridge will remain along
the Gulf Coast and up into Central Georgia. Weak low-level flow
will become southwesterly, helping maintain lower 70s dew points.
PWATs look to range from around 1.6 inches in West Alabama to near
2 inches in East Alabama. Scattered showers and storms are
expected to develop with daytime heating, with the highest chances
in East Alabama where the best moisture will be and near the
weakness in the ridge, and near possible remnants of an MCV.
Updraft intensity should be muted by warm mid-level temperatures
(500mb temps near -2C) which may limit lightning activity.
Guidance has trended slightly lower on highs with the ridge not
building in as quick, so heat indices look to remain less than 105
degrees. Subtropical ridging strengthens to around 596 decameters
on Saturday. Despite the strength of the ridge, PWATs at or above
2 inches should still allow for some scattered showers and (weak)
storms to develop, highest chances once again east. With the
moisture, guidance has trended slightly less hot, but with
elevated dew points a few spots could see heat indices approaching
105 depending on the competing factors of increasing Gulf
moisture and dry ground conditions.

Meanwhile a shortwave moving through the Great Lakes will cause a
cold front to sink southward into Tennessee on Sunday. Slight
height falls occur over Central Alabama as the ridge retrogrades a
bit westward. Higher dew points pooling south of the boundary will
result in the potential for heat indices to reach 105 degrees
across much of Central Alabama depending on how quickly convection
initiates in the tropical-like air mass. Latest guidance is
suggesting the lower dew points with the front may slip southward
into our northern counties Monday and Tuesday. This would result
in some reduced rain chances in the north, with a less humid but
still hot air mass. Meanwhile, enhanced dew points along and south
of the boundary will result in the potential for heat indices in
the 105-110 range. Exact placement of this boundary is subject to
change, though. Meanwhile, the ridge looks to build back to the
east Tuesday resulting in increasing temperatures as we go through
the holiday week.

32/Davis

&&

.AVIATION...
(18Z TAFS)
Issued at 111 PM CDT WED JUN 26 2024

Convection will spread eastward across the area this afternoon as a
cold front moves towards the region. Added TEMPOs at most TAF sites
for TSRA with PROB30s continuing overnight. Ceilings are expected to
plummet overnight with IFR conditions developing as early as
07-08Z.

86/Martin

&&

.FIRE WEATHER...

Moisture and chances for showers and storms increase across West
Alabama today, while RH values in East Alabama will still drop
into the 25 to 35 percent range. Scattered, mainly afternoon and
evening showers and storms are expected Thursday into the weekend,
with the highest coverage in the southeast. RH values will stay
above 45 percent in most areas.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     70  88  70  94 /  40  40  10  30
Anniston    72  89  72  93 /  40  50  10  40
Birmingham  72  89  73  95 /  40  40  10  30
Tuscaloosa  71  88  73  94 /  50  40  10  20
Calera      73  89  73  96 /  40  50  10  30
Auburn      73  89  72  93 /  20  60  20  40
Montgomery  73  90  73  94 /  40  60  20  40
Troy        72  89  71  93 /  30  60  30  50

&&

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

$$

SHORT TERM...86/Martin
LONG TERM....32
AVIATION...86/Martin