The Storm Prediction Center has introduced a moderate risk for severe storms for parts of Central Alabama tomorrow. There is a threat for a few strong tornadoes in the moderate risk area.

The moderate risk area is generally along and south of a line from Aliceville to Tuscaloosa to Clanton and along and west of a line from Clanton to Montgomery. At this time, the moderate risk only affects a small portion of Pickens, Bibb, and Chilton counties in our coverage area.

We will continue to monitor this event closely and bring you the latest updates.

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1236 PM CDT Sat Apr 18 2020

Valid 191200Z – 201200Z

…THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
NORTHEASTERN LA AND CENTRAL/SOUTHERN MS/AL…

…SUMMARY…
Numerous severe storms appear likely Sunday from east Texas to South
Carolina. Several strong tornadoes may occur from parts of
northeastern Louisiana into central/southern Mississippi and Alabama
Sunday afternoon and evening. A swath of damaging winds and a
continued tornado threat should also extend across Georgia and parts
of South Carolina through Sunday night. Large hail is likely over
much of the area as well.

…East Texas into the Lower Mississippi Valley and Southeast…
Mainly elevated storms posing an isolated large hail threat may be
ongoing Sunday morning in a low-level warm advection regime across
parts of MS/AL. This activity should spread eastward across AL into
parts of central/southern GA through the day as a weak,
low-amplitude shortwave trough shifts northeastward across the
Southeast. There appears to be some potential for the southern flank
of this activity to become surface based by Sunday afternoon across
parts of southern/central GA and vicinity. If this occurs, then all
severe hazards appear possible.

Across the southern Plains, a shortwave trough is forecast to
develop eastward through the day, eventually reaching the lower MS
Valley by Sunday evening, and continuing eastward across the
Southeast overnight. 50-70+ kt of mid-level flow attendant to this
shortwave trough will overspread these regions. At the surface, a
low will develop eastward across TX/OK to the lower MS Valley
through the day while gradually deepening. A warm front should lift
northward across parts of east TX into the lower MS Valley and
Southeast in response. The greatest severe weather threat Sunday
will likely focus along/south of this warm front. A cold front is
also forecast to sweep east-southeastward through the period in
tandem with the developing surface low.

Storms may form early in the period across parts of east TX as
large-scale ascent associated with the shortwave trough overspreads
an increasingly unstable warm sector. Steep mid-level lapse rates
and strong effective bulk shear should support a threat of isolated
large to very large (2+ inches) and damaging winds with any
supercells that initially develop. With time, the airmass across the
lower MS Valley downstream of this morning activity is forecast to
quickly destabilize as upper 60s to lower 70s surface dewpoints
spread northward in tandem with the warm front and as diurnal
heating occurs.

There is some concern about dominant storm mode, but effective shear
of 50-60+ kt will easily support supercell structures. A 40-50+ kt
low-level jet is also forecast to develop across parts of LA/MS and
vicinity by peak afternoon heating. A corresponding increase in
low-level shear combined with the strong deep-layer shear and
moderate to locally strong instability suggests the potential for
strong tornadoes with scattered supercells and clusters in a
corridor extending from northern LA into southern/central MS/AL
Sunday afternoon and evening. Scattered large hail and damaging
winds, some of which could be significant, may also occur. Given the
increased confidence in strong tornadoes occurring, a Moderate Risk
has been introduced across this area.

The shortwave trough and strong low-level jet will shift eastward
through the evening and overnight hours across AL into GA and parts
of SC. Eventually, upscale growth into one or more clusters should
occur. Both scattered damaging winds and a few tornadoes should be
the main threats. A couple of strong tornadoes with embedded
supercells within the cluster/line also appear possible across this
region given the very strong low-level shear that will be present.

..Gleason.. 04/18/2020