-- Discussion containing changed information from previous version are highlighted. --
791
FXUS64 KBMX 072058 CCA
AFDBMX

Area Forecast Discussion
National Weather Service
Birmingham AL 215 PM CDT Tue May 7 2024

...New LONG TERM...

.SHORT TERM...
-- Changed Discussion --
(This evening through Wednesday)
Issued at 131 PM CDT TUE MAY 7 2024

This afternoon.

The mid-level longwave ridge axis will move further to the east
of the area this afternoon while a zonal flow aloft with some
shortwave disturbances will move east over the area through the
afternoon and evening hours. Surface high pressure is centered
well offshore of the Southeast Atlantic Coast but is elongated and
extends west across much of Florida. Expect shower activity to
continue to develop across our western and central counties and
expand east with time. Some of the showers may build into
thunderstorms will be possible later this afternoon and into early
evening if enough instability materializes. Winds will be from
the southwest at 7-14 mph. High temperatures will range from the
mid 80s far north and northeast to the low 90s far south.

Tonight.

A more southwest flow develops over the area tonight as longwave
ridging moves further east over much of the Mid Atlantic and
Southeast Coastal areas while a large upper low spins over the
Western Dakotas. Surface high pressure will remain centered over
the Southwest Atlantic Basin, but will continue to nose westward
toward the Wiregrass Region. A few weak shortwaves in the mid
levels will continue to move east over the area, providing enough
uplift for a continuation in shower and storm chances, though this
will largely be concentrated across the northwest half of the
area. Showers will remain the predominant element, but a few
thunderstorms will remain possible. Some patchy fog may develop
across portions of the south and southwest before daybreak. Winds
will be from the south to southwest at 4-8 mph. Low temperatures
will range from the upper 60s far east to the low 70s far
southwest.

Wednesday.

The sprawling upper low will become centered over the South
Dakota and Nebraska border on Wednesday while little change occurs
at the surface with the forecast area remaining between high
pressure to our southeast and lower pressure across Texas,
extending northeast into the Midwest. Chances for showers and some
thunderstorms will be greatest generally along and north of the
Interstate 20 corridor with a scattered coverage. Isolated
coverage is expected elsewhere. Winds will be from the south to
southwest at 7-14 mph. Highs will range from the mid 80s in the
higher terrain east to the low 90s across the southwest and far
south.

05
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&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 159 PM CDT TUE MAY 7 2024

A rather active weather pattern is taking shape across the region
for the remainder of the work week with several windows for
strong/severe thunderstorm potential. A series of shortwave
impulses associated with an elongated trough situated from the
Northern Plains to the Intermountain Region will eject eastward
over the next 48 hours. The first of these impulses will aid in
pushing a weak surface to 850 mb boundary toward the region
Wednesday night. It`s highly likely that scattered strong to
severe convection will form into a MCS as it tracks east southeast
toward Alabama tomorrow night. The timing of this has slowed
somewhat so the boundary later thermodynamics would potentially be
less favorable for severe weather. However, the kinematics and
deep layer profiles still look sufficient for damaging wind
potential.

Thursday looks to be a bit of a question mark for a variety of
reasons. At these time scales it`s hard to time/pinpoint any
potential remnant convection or outflows from the overnight
MCS/QLCS. Any remnant boundaries or differential heating lines
could be a genesis for redevelopment. However, if some of the more
recent CAMs are correct and the overnight convection is even
slower then the afternoon might end up being mostly dry especially
across the northern half where the atmosphere would be
sufficiently overturned. Having said that, many of the point
soundings show a fairly volatile airmass with CAPES 2.5-3 Kj/kg
and 60 knots of bulk shear if the airmass is semi-pristine.

Based on the uncertainty have kept the PoPs on the higher end of
the guidance for Thursday and Thursday night. It should be noted
that the latest medium range guidance is still fairly consistent
with yet another convective complex impacting mainly southern
portions of Alabama Thursday night/early Friday. Subtle
differences in the track will determine whether the primary
impacts stay south of our forecast area. The profiles ahead of
this feature look to be fairly unstable with decent mid level flow
(but fairly weak low level flow) so this is another period that
will need to be monitored closely.

At this time, the weekend looks generally dry with some drier air
working in from the north. A shortwave and associated surface low
across the northern Gulf will bring rain back into the forecast
for Sunday and Monday along the coast. The medium range guidance
is edging north with this system and PoPs may need to included for
our southeast quadrant for Monday (and possibly Tuesday) if this
trend continues.


15/CBD

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1254 PM CDT TUE MAY 7 2024

Expect scattered to broken mid level clouds today with isolated
showers and a few thunderstorms to develop through the afternoon
and into the evening. Thunder potential is too low to include at
any terminal but shower activity potential is high enough to
include at all northern sites generally from 18 to 23z with
lingering shower potential at most northern sites through 04z
Wednesday morning. Chances for showers with a few thunderstorms will
become great enough to mention toward 15z Wednesday across the
northern sites. Clouds will continue to increase tonight into
Wednesday with some MVFR conditions overnight. Some reduction in
visibility is possible far south before daybreak Wednesday.

05
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&&

.FIRE WEATHER...

Isolated to scattered showers and storms are possible through
Wednesday with greater rain chances Wednesday night and Thursday.
Rainfall amounts will average 0.5-1.0 inch under heavier storms.
Afternoon minimum RH values will be above 45-50 percent each
afternoon through mid week. 20-foot winds will average less than
10 mph from the south to southwest through this evening,
increasing to 8-12 mph Wednesday and Thursday. Wind gusts to
around 25 mph are possible near convection.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     68  88  65  85 /  50  50  60  80
Anniston    68  87  69  85 /  40  50  40  80
Birmingham  70  89  69  86 /  50  40  60  80
Tuscaloosa  71  90  71  89 /  40  40  50  70
Calera      70  88  70  86 /  40  40  40  80
Auburn      68  87  72  86 /  20  30  10  70
Montgomery  70  91  72  89 /  20  20  10  60
Troy        69  90  72  89 /  10  20  10  50

&&

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

$$

SHORT TERM...05
LONG TERM....15
AVIATION...05