569
ACUS02 KWNS 221741
SWODY2
SPC AC 221739

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1239 PM CDT Wed May 22 2024

Valid 231200Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
NEBRASKA INTO NORTHERN KANSAS EASTWARD TOWARD THE MISSOURI RIVER...

...SUMMARY...
Severe thunderstorms are expected across parts of the central and
southern Plains into the Mid-South on Thursday. Damaging winds,
damaging hail and a couple of tornadoes will be possible. The
greatest concentration of severe wind is expected over parts of
Nebraska into northern Kansas late, where gusts over 80 mph are
expected.

...Synopsis...
Two primary shortwave troughs will exist on Thursday. The leading
trough will move from the Great Lakes into the Northeast late, with
another moving from the northern Rockies into the northern Plains.
To the south, moderate to strong mid and high level westerlies will
persist across the southern states, with embedded disturbances from
TX into the Southeast.

At the surface, a cold front will push east from NY into New England
during the day, while the westward extension of this boundary
becomes a warm front and lifts north across the Mid MS and lower MO
Valleys. Rich low-level moisture with 70s F dewpoints from TX to the
lower MS Valley will spread north across OK, AR, and into southern
KS and MO, in anticipation of the northern Plains shortwave trough.


During the afternoon, a surface trough will deepen from SD into
eastern CO, with a surging cold front moving rapidly south into the
central Plains overnight.

...Northern TX/OK into AR...
Areas of thunderstorms are likely to be ongoing from AR into TN
Thursday morning, with attendant midlevel wave moving quickly
eastward. Some of this activity could pose a damaging wind risk,
depending on level of organization at that time.

To the west, moisture and instability will build across the region
as southerly winds increase advection and the air mass over TX
recovers from the previous nights convection. Given the rapid
moisture return, substantial low clouds will be possible over much
of the area. Indeed, the steeper low-level lapse rates are forecast
to remain well west into from western KS into the TX Panhandle and
South Plains west of the dryline. Isolated, and perhaps short lived
activity cannot be ruled out along a very narrow zone there at peak
heating, with hail threat.

Otherwise, a large area of moisture and instability will
conditionally favor severe storms from OK to the ArkLaTex, however,
uncertainty exists regarding what will focus development. The
deepening moist layer may eventually erode CIN from below, in which
case storms that develop with clearly have very large hail potential
due to steep midlevel lapse rates and elongated hodographs. A brief
tornado or two may also occur.

...Central and northern Plains...
A very unstable air mass will develop during the afternoon, well
ahead of the developing cold front. Lapse rates aloft will be steep,
with low-level moisture rapidly spreading north during the evening.
Initial supercells are expected from west-central into central NE,
with an eventual severe MCS developing. Forecast soundings during
the evening indicate very steep lapse rates aloft and otherwise
supercellular wind profiles, however, given the eventual upscale
growth, a particularly severe MCS is forecast. Significant wind
gusts as well as wind-driven hail will be possible. In addition,
brief tornadoes are expected. This activity may reach the MO River
into Friday morning.

..Jewell.. 05/22/2024

$$