Severe Storm Outlook Narrative (AC)
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ACUS11 KWNS 201620
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Mesoscale Discussion 0299
NWS Storm Prediction Center Norman OK
1119 AM CDT Mon Mar 20 2017

Areas affected...Eastern Illinois into Indiana

Concerning...Severe potential...Watch unlikely

Valid 201619Z - 201845Z

Probability of Watch Issuance...20 percent

SUMMARY...Scattered storms will develop southeastward out of
northern Illinois and into Indiana today, with marginally severe
hail expected.

DISCUSSION...Warm advection out of the southwest persists across the
region, immediately in the wake of earlier storms which have
reinforced the stable surface with cool air. Storms have already
re-formed over northeastern Illinois, possibly associated with a
weak disturbance aloft preceding the larger-scale height falls to
the north.

Modest theta-e advection around 850 mb will persist today, aiding a
broad area of weak lift, with steep midlevel lapse rates and
increasing shear in the cloud-bearing layer helping to maintain this
cluster of cells as it continues southeastward across Indiana and
perhaps western Ohio later today. Given the cold surface air, severe
wind is not expected to be a threat.

..Jewell/Hart.. 03/20/2017

...Please see for graphic product...


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