918
FXUS64 KBMX 181604
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
1104 AM CDT Sat May 18 2024

...New SHORT TERM, AVIATION...

.SHORT TERM...
(This afternoon through Sunday)
Issued at 1102 AM CDT SAT MAY 18 2024

As has been the case the past 24 to 36 hours, the heaviest rain
and convective activity has remained well to our south over the
Gulf Coast region. A quasi-stationary boundary stretching from
west to east along a New Orleans to Mobile to Dothan line
continues to remain the focus for shower and storm development.
Southwesterly deep layer shear across the atmospheric profile and
plenty of tropical moisture will keep strong to severe storms and
flash flood potential across the Florida Panhandle and far
southeastern Alabama through the morning.

Meanwhile, a surface low is spinning close to Memphis helping to
trigger scattered to numerous showers and storms as cooler air
works in aloft. We should continue to see storm development as we
go through the remainder of the day, spreading southeastward with
time. Areas along and north of the I-20 corridor will see the best
coverage of showers and storms with sunshine starting to make an
appearance following low clouds and fog early this morning. As low
level instability increases, we`ll see enough shear aloft (60kts
at 500mb) with steep lapse rates to support strong to isolated
severe storms. With unidirectional shear profiles, isolated
damaging wind gusts and large hail will be the hazards this
afternoon through the early evening hours. Storms are expected to
decrease in coverage with the loss of daytime heating during the
evening hours tonight as the 500mb trough axis pushes off into
Georgia.

We`ll have to keep an eye on the potential for fog and low stratus
development overnight tonight. High-res guidance is hinting that
we may get enough clearing with calm winds for the development of
fog between midnight tonight and sunrise Sunday morning. I`ve
added in patchy fog in the forecast to trend that direction, but
more widespread fog may need to be added in the next forecast
update. Sunday will feature much drier conditions with northerly
flow at 700mb. A surface ridge over the Mid-Atlantic and Carolinas
will build southwestward by Sunday afternoon. What appears to be
a "back door" surface boundary will creep westward into our far
eastern counties, with some upper level shortwave energy to work
with. A few isolated showers and perhaps a storm can`t be ruled
out across the far east as a result. Otherwise, everyone else will
be dry and warm as upper heights begin to rise. Mid to upper 80s
will be common for highs by Sunday afternoon.


56/GDG

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 304 AM CDT SAT MAY 18 2024

Early to mid next week appears warm and dry across the Deep South. A
low-level ridge is progged to establish across the eastern CONUS
with a broad zone of split upper-level flow. Southerly surface winds
return to our area by Tuesday as high pressure centers near the East
Coast, and this will help tilt afternoon highs into the 90s for some
locations Tue & Wed. Meanwhile a lingering surface front will drape
from near the ArkLaTex through the Ohio Valley on Thursday, behind a
departing Great Lakes low pressure system. Medium-range guidance
depicts this front near/north of the I-40 corridor, but with an axis
of higher PWs spreading into the Tennessee Valley. As such, there
could be isolated to scattered afternoon convection Thursday, but
better PoPs are on Friday due to a shortwave currently progged to
pass over the Tennessee Valley. It`s too early to tell if there will
be any impacts.

40/Sizemore

&&

.AVIATION...
(18Z TAFS)
Issued at 1102 AM CDT SAT MAY 18 2024

Lower ceilings will continue to mix out between 16 and 18z, with
most terminals observing VFR conditions through the afternoon.
SHRA/TSRA development is expected to impact northern terminals
between 18z and 01z, with less coverage expected at MGM and TOI.
Amendments can be expected this afternoon, with rapid reductions
in visibility due to heavy rains along with variably gusty winds
within thunderstorms. SHRA/TSRA will decrease in coverage during
the evening hours between 03z and 06z. Low clouds and/or fog is
then expected to develop areawide after 09z with IFR ceilings.
Lower ceilings and fog should mix out between 13z and 15z Sunday
morning with VFR conditions expected through 18z Sunday.

56/GDG

&&

.FIRE WEATHER...

An area of showers and storms will move across south Central
Alabama this morning, before scattered to numerous showers and
storms are expected area wide this afternoon and evening. Min RH
values today will range from 65 to 75 percent, with southwesterly
20ft winds at less than 10mph. Rain chances decrease Sunday, and
along with warmer daytime temperatures, minimum RH values will be
in the 50 to 60 percent range. 20ft winds become north to
northwesterly, but remain at 5-8mph.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     80  61  85  61 /  80  40  20   0
Anniston    79  62  84  63 /  70  50  20   0
Birmingham  81  63  85  65 /  80  40  10   0
Tuscaloosa  82  64  87  65 /  70  30   0   0
Calera      80  64  85  65 /  70  40  10   0
Auburn      77  64  82  64 /  70  50  20   0
Montgomery  81  65  85  65 /  60  50  10   0
Troy        79  65  84  64 /  80  40  10   0

&&

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

$$

SHORT TERM...56/GDG
LONG TERM....40
AVIATION...56/GDG