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ACUS11 KWNS 231824
SPC MCD 231823

Mesoscale Discussion 1776
NWS Storm Prediction Center Norman OK
1223 PM CST Thu Nov 23 2017

Areas affected...central Florida

Concerning...Severe potential...Watch unlikely

Valid 231823Z - 232030Z

Probability of Watch Issuance...20 percent

SUMMARY...Threat for a couple of damaging wind events and a brief
tornado will persist through mid afternoon, primarily in a narrow
corridor across north central FL. Overall threat appears too
marginal for a WW.

DISCUSSION...Storms have undergone some intensification as they
moved onshore just north of Tampa, possibly due to interaction of
attendant ne-sw oriented convergence boundary with the seabreeze.
Stationary front extends from just north of Tampa to north of
Melbourne, and visible imagery shows thinning cirrus, allowing
modest diabatic warming of the boundary layer in the warm sector
where MLCAPE ranges from 500 to 800 J/kg over central FL. Models
indicate there should be some tendency for low-level winds to veer
and weaken as a low-amplitude shortwave trough moves east of the
peninsula later this afternoon. In the meantime, the more favorable
low-level hodographs with 150-250 storm-relative helicity will
persist in vicinity of the stationary front. Storms moving east and
interacting with this boundary may develop occasional supercell
structures and bowing segments, posing a risk for locally strong to
damaging wind gusts and a brief tornado. The marginal thermodynamic
environment and tendency for the low-level winds to veer and weaken
later this afternoon suggest overall threat should remain limited.

..Dial/Hart.. 11/23/2017

...Please see for graphic product...


LAT...LON   28538243 28818191 29178131 29198101 29008096 28628148
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