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ACUS01 KWNS 230059
SPC AC 230058

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0758 PM CDT Sun Jul 22 2018

Valid 230100Z - 231200Z


A few severe storms remain possible across parts of the
central/northern Plains and the Southeast this evening.

...Northern/Central Plains...
Scattered thunderstorms have developed along a surface trough
extending from the High Plains of eastern Colorado north/northeast
to North Dakota. The largest overlap of favorable surface-based
buoyancy and adequate effective shear exists across central Nebraska
and South Dakota, and isolated severe supercells, capable of large
hail and damaging winds, have organized in response. Modest 500mb
westerlies and weak southerly flow from the surface through 850mb
(noted in the 00Z LBF sounding) are yielding south/southeasterly
storm motions, which will gradually take cells away from large-scale
ascent. In time, this evolution will combine with increasing
inhibition to favor a downward intensity trend by early tonight.

A convective complex and its trailing stratiform region have
stabilized much of the northern Florida Peninsula this evening.
While an isolated damaging gust or two may occur near the Nature
Coast, continued progression of outflow towards the southwest should
further reduce the threat this evening. To the north, pockets of
residual instability exist in southeast Georgia, generally where
outflow/sea breeze has yet to pass. An isolated supercell or two may
remain possible through late evening, given continued strong
effective shear (around 40-45 kt from the KVAX VWP). However,
further stabilization of the boundary layer will keep the threat of
damaging winds and large hail isolated at most. Lastly, a couple
strong/severe storms may develop through the early overnight over
southern Alabama and the western Florida Peninsula, owing to
convergence along the surface front and subtle ascent within
northwest flow. However, 00Z regional RAOBs indicate dry air aloft
will be tough to overcome on more than a very spotty basis within
this weakly forced regime.

..Picca.. 07/23/2018