857
ACUS02 KWNS 040614
SWODY2
SPC AC 040612

Day 2 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0112 AM CDT Fri Apr 04 2025

Valid 051200Z - 061200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE LOWER TO MID MISSISSIPPI VALLEY...

CORRECTED FOR SW TX THUNDER LINE

...SUMMARY...
Severe storms, capable of producing damaging wind gusts, large hail
and several tornadoes are expected from Saturday into Saturday night
from the Sabine River Valley northeastward into the lower to mid
Mississippi and Ohio Valleys. Strong tornadoes, very large hail, and
severe gusts above 70 mph will be possible in parts of the lower to
mid Mississippi Valley.

...Sabine Valley/Lower to Mid Mississippi Valley...
A mid-level trough and an associated jet streak will move eastward
across the southern Plains on Saturday. During the morning, a large
MCS will be located along a cold front from the Ark-La-Tex
northeastward into the mid Mississippi Valley. Ahead of the MCS, a
very moist airmass will be in place with surface dewpoints in the
upper 60s and lower 70s F. Moderate instability is expected early in
the day across this moist airmass. Due to the instability already in
place, thunderstorms along the front will likely develop a severe
threat Saturday morning. Severe wind gusts and isolated large hail
are expected to be the initial threats.

The storms will gradually move eastward into a 50 to 60 knot
low-level jet, located from central Louisiana northeastward into
eastern Arkansas. This jet, along with around 50 knots of 0-6 km
shear, will create favorable deep-layer and low-level shear for
supercells and tornadoes. Forecast soundings near the axis of the
low-level jet from late morning into the afternoon on Saturday have
0-3 Km storm-relative helicity of 250 and 350 m2/s2. This will
support a tornado threat, associated with supercells and bowing line
segments. The more intense supercells could produce strong
tornadoes, with the greatest threat located from central Louisiana
to southeast Arkansas. The storms could also produce hailstones
greater than 2 inches in diameter.

As the entire MCS moves eastward across the lower to mid Mississippi
Valley during the morning and afternoon, widespread damaging-wind
gusts will become likely along a line that is expected to become
increasingly organized during the day.  The more intense components
of the line could produce damaging wind gusts above 70 mph. The
severe threat with this line is expected to continue from late
afternoon into the early to mid evening as it moves into the central
Gulf Coast states.

...Ohio Valley...
A mid-level trough will move eastward across the Upper Midwest on
Saturday, as a cold front advances southeastward into the Ohio
Valley. Thunderstorms are expected to be ongoing along the front at
the start of the period, with storms moving gradually eastward into
the Ohio Valley during the day. Ahead of the storms, an axis of
instability is forecast to develop by midday from western Kentucky
into southeast Indiana and southern Ohio. In addition to the
instability, low-to-mid level flow is forecast to increase across
the Ohio Valley during the day, as heights fall associated with the
approach of the mid-level trough. Forecast soundings near the
instability axis in western and central Kentucky around midday on
Saturday have MLCAPE peaking in the 500 to 750 J/kg range, and have
0-6 km shear around 50 knots. The environment should support
embedded supercells and bowing line segments. The primary threats
are expected to be damaging-wind gusts and hail, but an isolated
tornado threat will also be possible.

..Broyles.. 04/04/2025

$$