287
ACUS01 KWNS 201635
SWODY1
SPC AC 201633

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1133 AM CDT Mon May 20 2024

Valid 201630Z - 211200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS
OF THE CENTRAL HIGH PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
NORTHERN ILLINOIS AND SOUTHERN WISCONSIN...

...SUMMARY...
The primary threat for severe thunderstorms today will be over parts
of the central Plains, with large hail, damaging wind gusts, and a
few tornadoes possible.

...Central High Plains...
A large upper trough will slowly deepen across the western United
States today, with strengthening southwesterly mid/upper level flow
spreading across the Plains states.  A band of mid-level moisture
and instability will result in scattered high-based thunderstorms
across northern CO/southern WY by mid-afternoon, capable of locally
damaging wind gusts.  Other discrete supercell storms may form in
vicinity of the DCVZ as southeasterly low-level winds and elevated
terrain aid in initiation.  These storms will track
east-northeastward into a progressively more moist/unstable air
mass, with the risk of very large hail and a few tornadoes through
the evening.  By mid-evening, coverage of storms will increase over
southwest NE as a southerly low-level jet strengthens, with storms
progressing across the central Plains overnight with a continued
risk of large hail and damaging winds.

...IL/WI...
A well-defined remnant MCV from overnight convection over KS is
currently over northeast IA.  A surface boundary extends eastward
from the low across northern IL.  Broken clouds and partial
afternoon heating will aid in the development of thunderstorms near
the MCV later today as it tracks across southern WI/northern IL.
Any storm that can interact with the boundary would have the
potential to become a supercell and pose a risk of a tornado or two.
 Otherwise, hail and gusty winds could occur with the strongest
cells.

...Southeast FL...
Widely scattered afternoon thunderstorms are possible across
southeast FL.  Ample low-level moisture, strong heating, cyclonic
midlevel flow, and relatively steep lapse rates could result in a
strong storm or two capable of gusty winds and hail.

..Hart/Wendt.. 05/20/2024

$$