Tornado Watch 471

Issued

Aug 27, 2017, 12:40 PM CDT (17:40 UTC)

Expired

Aug 28, 2017, 2:00 AM CDT

In force

13 hr

Issued by

the Storm Prediction Center

Largest hail expected

0.5 in

Strongest gust expected

50 kt

Counties Acadia Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Jefferson Davis Parish, LA, Vermilion Parish, LA, Brazoria County, TX, Chambers County, TX, Fort Bend County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jefferson County, TX, Liberty County, TX, Orange County, TX

The Houston radar (KHGX), 64 km from the middle of the area, began a volume at 17:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Two or more tornadoes

50%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

10%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

5%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

30%

• Mesoscale Discussion 1585Aug 27, 10:54 AM CDT
• Mesoscale Discussion 1587Aug 27, 3:07 PM CDT
• Mesoscale Discussion 1588Aug 27, 6:04 PM CDT
• Mesoscale Discussion 1590Aug 27, 9:50 PM CDT

507 
WWUS20 KWNS 271737
SEL1  
SPC WW 271737
LAZ000-TXZ000-CWZ000-280700-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 471
NWS Storm Prediction Center Norman OK
1240 PM CDT Sun Aug 27 2017

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southwest Louisiana
  Southeast Texas
  Coastal Waters

* Effective this Sunday and Monday morning from 1240 PM until 200
  AM CDT.

* Primary threats include...
  A few tornadoes possible

SUMMARY...The risk for brief tornadoes will continue into early
Monday in association with tropical cyclone Harvey.

The tornado watch area is approximately along and 55 statute miles
north and south of a line from 30 miles west northwest of Angleton
TX to 65 miles east southeast of Lake Charles LA. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).

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.

&&

OTHER WATCH INFORMATION...This tornado watch replaces tornado
watch number 470. Watch number 470 will not be in effect after
1240 PM CDT. 

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0.5 inches. Extreme turbulence and surface wind
gusts to 50 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 16030.

...Grams

Tornado Watches in Texas, 2017Tornado Watches in Louisiana, 2017Every tornado watch in 2017

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.