088
FXUS64 KBMX 052053
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
353 PM CDT Sun May 5 2024

...New LONG TERM...

.SHORT TERM...
(This afternoon through Monday)
Issued at 1159 AM CDT SUN MAY 5 2024

This afternoon, southerly flow will bring moisture and warm air to
the area. Isolated diurnal convection is expected across the entire
state. A few thunderstorms could be momentarily strong with
instabilities between 1500 and 2000 j/kg, and a weak wind profile
aloft. Anything that does form could produce high rainfall rates
with PW values around the 90th percentile for this time of year.
Highs today will be in up to 5-7 degrees above normal.

This evening, a weak low will approach from the east and move to the
north and northeast across northern MS. Activity associated with
this low is expected to move towards Alabama, but weaken as it
reaches the state line. Scattered showers and thunderstorms will be
expected with this system passing. The main coverage is going to
be across the northern half of the state, closer to the system as
it moves to the northeast. The southern half of the state could
see isolated showers and maybe an isolated thunderstorm, though
the greater instability and forcing will be across the northern
half of the state.

A weak mid level jet will move through overnight, allowing for the
wind profile to increase in speed, though instabilities will be
decreasing after sunset tonight. Will maintain that a few isolated
storms in the northern half of the state could be strong with the
forcing present. PW values will remain high with high rainfall rates
possible. By early morning Monday, before sunrise, most activity
should move east. With plenty of low level moisture, there could be
fog in several areas, especially in the south and west where the
rain will end earlier in the night, and the clouds are expected to
become more broken. In areas of the north and east, overcast skies
are expected to remain through much of the night, limiting fog
development. Will have to keep an eye on how quickly/slowly the rain
moves east to determine coverage of any fog that develops.

Monday, upper levels take on a more westerly direction with PW
values decreasing from around 1.6 to around 1.2 or 1.3 inches, which
is around the 75th percentile. Isolated to scattered diurnal
convection is expected through the early afternoon into the evening
across all of Central AL. A few CAMs are showing increased
instabilities, closer to around 2500 j/kg in the western half of the
state , though the wind profile still appears weak. All activity
should weaken with sunset. High temperatures on Monday will be
several degrees above normal.

24

&&

.LONG TERM...
(Monday night through next Saturday)
Issued at 353 PM CDT SUN MAY 5 2024

Made minor adjustments to rain chances/rain areas through the
beginning of the week, as a messy westerly to southwesterly flow
brings opportunities for rain and storms. Temperatures remain
warm, with highs in the upper 80s to lower 90s most days.

Looking to the late week system, a cold front arrives Thursday
afternoon as the shortwave moves off to the east. The airmass over
the area will certainly carry quite a bit of instability with
strong shear values for early May, with high lapse rates over 7.5
C/km. Will not include a mention of severe storms for Central
Alabama at this time, for a few reasons. A MCS along the front
will be ongoing to our northwest Wednesday night, likely racing
ahead of any surface boundary. A decaying line of storms will move
into the area in Thursday morning, likely stabilizing the
airmass. Assuming the airmass recovers, upper level support is
moving away from the area with briefly zonal flow aloft, when the
front arrives in the northwest mid to late afternoon. Another
shortwave rides along the front Thursday evening, resulting in
convection across southern areas, where PWs approach 2 inches. The
severe focus would likely shift to our south during this
timeframe.

14

Previous long-term discussion:
(Monday night through next Saturday)
Issued at 335 AM CDT SUN MAY 5 2024

An unsettled weather pattern will be in place during the coming
week. Shower and thunderstorm chances will run each day through
early Friday morning, as a late season cold front sweeps through
Central Alabama. Convection across the northwestern counties Tuesday
and Wednesday may be strong and will need to be monitored for any
isolated severe potential in the form of damaging wind and hail.

Meanwhile, strong southerly surface flow will bring some of the
warmest days so far this year. Winds may gust as high as 15-20 mph
at times Tuesday, Wednesday, and Thursday. High temperatures will
soar into the upper 80s, perhaps even lows 90s across the southern
counties, Tuesday through Thursday.

We are beginning to monitor the Thursday evening timeframe for the
potential for strong to severe thunderstorms associated with an MCS-
like setup moving west to east across the area. This, in advance of
the aforementioned cold front, may pose a damaging wind and hail
threat, owing to fairly steep lapse rates around 7.5 C/km and bulk
shear values of 50-55 kts. However, the better forcing will be
removed to the north of Alabama, so will need to further evaluate
the potential over the next few forecast cycles.

12

&&

.AVIATION...
(18Z TAFS)
Issued at 1159 AM CDT SUN MAY 5 2024

Scattered showers and thunderstorms will develop across the state
this afternoon. Due to uncertainty in timing and coverage, have
left VCSH in for now and will update if convection appears to
impact any TAF site. Overnight, a low pressure will bring more
scattered activity, mainly to all sites but KMGM and KTOI through
the early morning Monday. Plenty of low level moisture could keep
clouds at MVFR overnight. Depending on timing and amount of
rainfall overnight, KMGM and KTOI might see fog development.
Confidence was low so left mention out of TAF for now.

24

&&

.FIRE WEATHER...

Isolated to scattered showers and storms are possible each day
through Tuesday. Rainfall amounts will average 0.5-1.0 inch under
heavier storms. Afternoon minimum RH values will be above 40-45
percent each afternoon. 20- foot winds should average less than 10
mph from the south to southwest, though gusts to around 25 mph
will be possible at times.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     65  86  64  87 /  60  40  20  40
Anniston    66  86  66  87 /  50  40  20  30
Birmingham  68  86  67  87 /  50  40  10  40
Tuscaloosa  68  86  68  87 /  50  40  10  40
Calera      68  85  67  85 /  50  40  10  40
Auburn      69  85  67  86 /  30  40  10  20
Montgomery  69  89  67  90 /  20  40   0  20
Troy        67  89  67  89 /  20  40   0  20

&&

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

$$

SHORT TERM...24
LONG TERM....14
AVIATION...24