607
ACUS01 KWNS 231952
SWODY1
SPC AC 231950

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0250 PM CDT Thu May 23 2024

Valid 232000Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
NEBRASKA INTO WESTERN IOWA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
PLAINS...OVER PARTS OF KENTUCKY AND TENNESSEE...AND EASTERN MAINE...

...SUMMARY...
Severe thunderstorms are possible today across parts of the Plains,
Tennessee Valley, and Maine.  A concentration of particularly
damaging winds is forecast from Nebraska into western Iowa this
evening into tonight.

...NE into IA...
Severe probabilities for wind have been nudged eastward into more of
IA to account for an MCS accelerating a bit faster than shown by the
models.

...Western OK and TX...
A narrow north-south zone of hail potential exists near a dryline,
however, confidence is not high regarding how many storms will
occur. As such, will maintain overall Slight Risk with 15% SIG hail
probabilities. For specific information on this regime, see
mesoscale discussion 912.

..Jewell.. 05/23/2024

.PREV DISCUSSION... /ISSUED 1119 AM CDT Thu May 23 2024/

...Northern Plains...
Visible satellite imagery shows strong daytime heating occurring
across much of the central and northern Plains, with southerly
low-level winds drawing moisture northward into the region.
Dewpoints will only be in the 50s across ND/SD/NE/KS this afternoon
as initial thunderstorms develop ahead of a potent upper trough and
associated mid-level speed max.  These initial storms will be
relatively high-based supercells capable of very large hail and
damaging winds.  A tornado or two is also possible.  As the evening
progresses,  model guidance is in strong agreement that storms will
grow upscale into a fast-moving QLCS with an enhanced risk of
damaging winds across much of central/eastern NE into western IA.

...Southern Plains...
Multiple rounds of thunderstorms over TX during the past 24 hours
have resulted in a complex surface pattern, with pockets of
low-clouds and more stable air.  This tends to limit the confidence
in where robust thunderstorms will form later today.  Two areas of
concern are 1) western OK/northwest TX along the dryline, and 2)
central/north TX in vicinity of remnant outflow boundaries.  In both
areas, very large CAPE values and favorable vertical profiles will
favor supercell storms capable of very large hail, damaging winds,
and a tornado or two.  Considered adding an small ENH to western OK,
but there wasn`t sufficient confidence on where to place it.

...Maine...
Thunderstorms are beginning to develop along a cold front extending
from NH into Quebec.  Strong heating is occurring ahead of the front
across ME, where a few severe storms are possible later today.  See
MCD #909 for further details.

...TN Valley...
Strong heating is ongoing across parts of middle/east TN and central
KY.  Dewpoints near 70F will likely lead to a cluster of
thunderstorms this afternoon.  Forecast soundings show sufficient
westerly flow aloft and steep low-level lapse rates to pose a risk
of damaging wind gusts and hail in the strongest cells.

$$