Mesoscale Discussion 2169
NWS Storm Prediction Center Norman OK
0258 PM CDT Thu Sep 21 2023
Areas affected…portions of southern Oklahoma and adjacent North
Concerning…Severe potential…Watch possible
Valid 211958Z – 212200Z
Probability of Watch Issuance…40 percent
SUMMARY…Thunderstorms are forecast to increase in coverage over
the next few hours, with local/limited severe threat potentially
evolving. WW issuance may need to be considered in the next 1 to 2
DISCUSSION…Filtered heating of a moist low-level airmass over the
Oklahoma/Texas vicinity has supported afternoon destabilization,
with 1000 to 2000 J/kg mixed-layer CAPE now observed. As a weak
disturbance at mid levels progresses eastward across the Red River
Valley area this afternoon, a cluster of thunderstorms has
developed, and is currently centered over south central Oklahoma.
Additional storm development is expected across this area over the
next few hours.
While low-level flow remains relatively weak, a belt of enhanced
(around 40 kt) westerly mid-level flow associated with the
aforementioned disturbance will continue to spread across this
region. This will contribute to shear sufficient for organized
storms, and associated potential for marginal hail/wind risk with
stronger storms. Some CAMs have hinted at potential for
upscale/linear growth later on, which could increase the wind
potential into this evening.
While storms have been slow to organize/strengthen, some recent
intensification is noted over the Murray County OK vicinity. We
will continue to monitor evolution of severe-weather potential
across this area, along with any need for WW issuance.
…Please see www.spc.noaa.gov for graphic product…
LAT…LON 33489872 33919829 34499790 34819751 35129603 34739509
33889489 32889543 33039726 33489872