Mesoscale Discussion 1976
NWS Storm Prediction Center Norman OK
0220 AM CDT Fri Aug 14 2026
Areas affected...Central/eastern NE into western/central IA and
extreme southeast SD
Concerning...Severe potential...Watch unlikely
Valid 140720Z - 140945Z
Probability of Watch Issuance...20 percent
SUMMARY...Strong to locally severe storms are possible overnight.
DISCUSSION...A bowing segment associated with a long-lived MCS is
moving northeastward across south-central NE. While this system has
generated a well-defined MCV, convection has shown a weakening trend
early this morning, with only sporadic severe gusts noted over the
last 1-2 hours. Some rejuvenation of convection along the gust front
cannot be ruled out as it moves within an elevated buoyancy gradient
and zone of low-level warm advection, but the remaining severe-gust
threat with this system is currently expected to remain isolated.
Farther east, an arc of elevated convection has developed early this
morning from northeast NE into southwest IA. This convection has
developed within the warm-advection regime to the north of a surface
front draped across northern KS/MO. Storms may continue to increase
in coverage as they spread northeastward with time overnight.
Relatively steep midlevel lapse rates and MUCAPE increasing above
2000 J/kg will favor vigorous updrafts. Mid/upper-level flow is
generally weak, and effective shear for storms rooted around 850 mb
is less than 30 kt. Given the weak shear, the overnight severe
threat is expected to remain rather isolated. However, effective SRH
will be more favorable for storms that can become rooted closer to
the surface, which could result in at least transient storm
organization. Isolated hail will be possible with the strongest
cells, while the favorable buoyancy and large PW (near/above 2
inches) will support localized downburst potential, even with the
persistence of a near-surface stable layer.
..Dean/Mosier.. 08/14/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DMX...FSD...OAX...GID...LBF...
LAT...LON 40849411 41289564 40989676 40739773 40439832 40839870
41179917 41479922 41859936 42229915 42659840 42809680
43019447 42629239 41299264 41109320 40849411
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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