ACUS02 KWNS 220559
SWODY2
SPC AC 220557

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Mon Sep 22 2025

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN
OKLAHOMA...FAR NORTHEAST TEXAS...AND MUCH OF ARKANSAS...

...SUMMARY...
Strong to severe storms are possible from the southern Plains to the
Tennessee Valley on Tuesday. Strongest thunderstorm activity is
expected across eastern Oklahoma into northeastern Texas and
Arkansas, where supercells capable of all severe hazards are
possible by afternoon.

...Synopsis...
A positively tilted mid-level trough will begin the period across
eastern Colorado and shift east through the day to the Missouri
Valley region by 12Z Wednesday. A 40 to 50 knot mid-level jet streak
associated with overnight convection Monday night across KS/OK will
shift east across MO/AR during the day Tuesday and gradually weaken.
In its wake, the primary mid-level jet streak will emerge across
Oklahoma and strengthen Tuesday night as it moves from Oklahoma into
Arkansas. A weak surface low is forecast to be across northwest
Oklahoma Tuesday morning. This surface low and its associated cold
front will drift slowly east through the day.

...Eastern Oklahoma into much of Arkansas and northeast Texas...
A large MCS will likely be ongoing Tuesday morning across eastern
Kansas, southwest Missouri, and northeast Oklahoma on the nose of a
40 to 50 knot low-level jet. As the low-level jet weakens during the
morning and storms move east of the greatest shear/instability,
expect the MCS to weaken. Some isolated damaging wind gusts may
persist across northern Arkansas/southern Missouri and into TN/KY,
but expect this activity to remain mostly sub-severe.

The primary severe weather concern will be Tuesday afternoon/evening
across eastern Oklahoma and western Arkansas. Strong instability is
forecast across this region in the wake of the morning MCS as cool
temperatures aloft overspread low to mid 70s dewpoints. RAP/NAM
forecast soundings show only modest heating is necessary to erode
inhibition. Therefore, expect additional thunderstorm development
during the afternoon along and ahead of the cold front as it moves
across Oklahoma. Storm motion orthogonal to the front should favor
movement along and perhaps off of the front and into the warm
sector. Therefore, all severe hazards will be possible across this
region in a favorable environment featuring strong instability,
moderate deep-layer shear, and elongating, cyclonically curved
hodographs.

A conditional, potentially more volatile tornado threat is possible
across eastern Oklahoma and western Arkansas if significant
destabilization can occur north of any outflow boundary left by
morning convection. 03Z RAP/00Z NAM forecast soundings near Fort
Smith capture this conditional environment well and would
potentially support strong tornadoes. However, this evolution is
highly dependent on the evolution of Day 1 convection across Kansas
and Oklahoma which still remains unclear. In addition, the time
window for this favorable environment would be narrow which also
adds conditionality to the risk. This scenario will be monitored
closely and a Level 3/Enhanced Risk may be justified in later
outlooks if this scenario appears more likely.

...Central Texas...
Moderate instability is forecast across central/northern Texas
Tuesday afternoon with eroding inhibition by mid-afternoon. Shear
will be relatively weak, but will increase during the
afternoon/evening as the mid-level jet streak drifts south. The most
favorable zone for thunderstorm development will be the triple point
where the cold front and dryline intersect across North Texas.
However, additional isolated storms may also develop along the
dryline and cold front. Isolated large hail and damaging wind gusts
will be the primary threat from these storms Tuesday
afternoon/evening.

...Tennessee Valley...
A weak warm front may be a focus for storm development Tuesday
afternoon/evening across western/middle Tennessee as moderate
instability develops across the region. Deep-layer shear should
remain quite weak (less than 20 knots) as the primary mid-level jet
streak remains farther west. However, a few stronger storms capable
of damaging wind gusts may develop during the afternoon/evening.

..Bentley.. 09/22/2025

$$
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