Mesoscale Discussion 2052
NWS Storm Prediction Center Norman OK
1241 AM CDT Sat Aug 26 2023
Areas affected…far southeastern Nebraska…northeastern
Kansas…far southern Iowa…and northern Missouri
Concerning…Severe potential…Watch unlikely
Valid 260541Z – 260815Z
Probability of Watch Issuance…20 percent
SUMMARY…Locally strong thunderstorms within a complex ongoing over
southeastern Nebraska/northeastern Kansas will likely continue
overnight, spreading eastward with time and possibly accompanied by
local/isolated/occasional severe-weather occurrences.
Isolated/local nature of the risk should preclude serious WW
DISCUSSION…Latest radar composite shows vigorous storms — within
a broader mesoscale system — moving across southeastern
Nebraska/northeastern Kansas, in tandem with an eastward-moving
mesolow near the southeastern Nebraska/northeastern Kansas border.
The storms are ongoing just north of a west-to-east surface frontal
zone, where a very moist boundary layer and associated axis of
moderate mixed-layer CAPE (1500 to 2500 J/kg exists).
With the instability axis extending eastward across northern
Missouri to central Illinois, and presence of low-level ascent near
the frontal zone, it appears likely that the organized system will
be sustained as it moves eastward with time.
Despite more than ample thermodynamic support, severe threat should
overall remain hindered by very modest deep-layer west-northwesterly
flow through the lower and middle troposphere. A very slightly
boundary layer near — and especially to the cool side — of the
surface front should also curtail more widespread/organized
damaging-wind risk. Still, local potential for marginal hail, and
an occasional strong gust near severe levels, will be possible over
the next several hours. At this time, barring
substantial/unanticipated organization of the convection linearly,
WW issuance will remain unlikely given the expected
isolated/sporadic nature of the risk.
…Please see www.spc.noaa.gov for graphic product…
LAT…LON 39499678 40199631 40519553 40619376 40439228 40259019
38999004 38689101 39099444 39169674 39499678