SPC Tornado Watch 9

WW 9 TORNADO LA TX CW 210120Z - 210800Z

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 9
NWS Storm Prediction Center Norman OK
720 PM CST Fri Jan 20 2017

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southwestern and south-central Louisiana
  Extreme southeast Texas
  Coastal Waters

* Effective this Friday night and Saturday morning from 720 PM
  until 200 AM CST.

* Primary threats include...
  A few tornadoes possible
  Scattered damaging wind gusts to 70 mph possible
  Isolated very large hail events to 2.5 inches in diameter
    possible

SUMMARY...A cluster of thunderstorms over southeast Texas appears to
be the start of a more expansive overnight severe-storm event moving
east-northeastward through this watch (and eventually beyond). 
Additional, more isolated severe storms also may form ahead of the
main complex, along and south of a returning marine/warm frontal
zone.  The tornado threat, while marginal at first, will increase
with time and with eastward extent across the watch area tonight,
into southern Louisiana, as shear and instability increase.

The tornado watch area is approximately along and 50 statute miles
north and south of a line from 20 miles southwest of Port Arthur TX
to 25 miles northeast of Lafayette LA. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU9).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean
storm motion vector 25030.

...Edwards

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