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825
ACUS11 KWNS 140922
SWOMCD
SPC MCD 140921
IAZ000-MOZ000-NEZ000-141045-

Mesoscale Discussion 1711
NWS Storm Prediction Center Norman OK
0421 AM CDT Sat Oct 14 2017

Areas affected...Southeast NE into southwest IA

Concerning...Severe potential...Watch unlikely

Valid 140921Z - 141045Z

Probability of Watch Issuance...5 percent

SUMMARY...Some hail will be possible with elevated storms spreading
from southeast NE into IA, but the hail is expected to remain
sub-severe.

DISCUSSION...Elevated convection is ongoing in a cluster over
southeast NE, near the terminus of a 50-kt west-southwesterly LLJ,
and along the northern gradient of buoyancy rooted in the 850-750 mb
layer.  The associated zone of low-level warm advection will spread
east-northeastward from NE into IA through the pre-dawn hours, as
will the elevated convection.  MUCAPE of 500-1000 J/kg with midlevel
lapse rates of 7-7.5 C/km and effective bulk shear near 40 kt could
support some storms with low-end supercell characteristics, the
strongest of which could produce some hail.  However, the somewhat
marginal buoyancy and messy storm modes will tend to limit the
threat for hail at or above 1" in diameter.

..Thompson/Edwards.. 10/14/2017

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

ATTN...WFO...DMX...EAX...OAX...

LAT...LON   41429351 41069349 40779370 40339559 40079684 40259719
            40599723 41089658 41549547 41669402 41429351