056
ACUS11 KWNS 081949
SWOMCD
SPC MCD 081949
IAZ000-NEZ000-082145-

Mesoscale Discussion 2270
NWS Storm Prediction Center Norman OK
0249 PM CDT Tue Sep 08 2026

Areas affected...portions of extreme eastern Nebraska into central
Iowa

Concerning...Severe potential...Watch possible

Valid 081949Z - 082145Z

Probability of Watch Issuance...60 percent

SUMMARY...Thunderstorms should gradually increase in coverage and
intensity as a surface cold front approaches. The strongest storms
may be accompanied by at least a few severe gusts and perhaps a
tornado or two. Convective trends are being monitored for the need
of a WW issuance.

DISCUSSION...A relatively broad swath of precipitation is currently
overspreading central NE into the northern half of IA, ahead of a
surface cold front, which has limited insolation and boundary-layer
destabilization across much of the region thus far. However, ample
boundary-layer mixing is underway to the southern periphery of this
rain band, where surface temperatures have heated into the 90s F (to
near 100 F in some spots). Given low to mid 70s F surface dewpoints,
MLCAPE has boosted to over 2000 J/kg despite mediocre mid-level
lapse rates.

It is unclear precisely when storms will initiate since much of the
available deep-layer ascent will glance the region to the north.
Nonetheless, a pre-frontal trough is gradually drifting east across
far southeastern NE, and this boundary may serve as a potential
focusing mechanism for more robust surface based thunderstorm
development over the next few hours. Storms may initially be
semi-discrete and anafrontal in nature. As the storms mature, and
assuming they can propagate into the warm sector, then surface-based
convection will become possible. These storms would most likely
become an MCS capable of producing a few severe gusts and perhaps a
couple of QLCS tornadoes.

A Severe Thunderstorm Watch may be needed when convective initiation
and intensification become more apparent.

..Squitieri/Hart.. 09/08/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...DVN...DMX...OAX...

LAT...LON   41149681 41829577 42539383 42569145 42379101 41649098
            41089215 40769469 40649550 40599628 41149681

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN