

413 

WWUS20 KWNS 051842

SEL2

SPC WW 051842

AZZ000-060300-



URGENT - IMMEDIATE BROADCAST REQUESTED

Severe Thunderstorm Watch Number 512

NWS Storm Prediction Center Norman OK

1145 AM MST Tue Oct 5 2021



The NWS Storm Prediction Center has issued a



* Severe Thunderstorm Watch for portions of

  Arizona



* Effective this Tuesday morning and evening from 1145 AM until

  800 PM MST.



* Primary threats include...

  Scattered damaging winds and isolated significant gusts to 80

    mph possible

  Scattered large hail and isolated very large hail events to 2

    inches in diameter possible

  A tornado or two possible



SUMMARY...Ahead of an upper system over southern California and the

Lower Colorado River Valley, strong to severe thunderstorms are

expected to develop within a very moist and unstable environment,

with the initial stronger storms expected across

west-central/south-central Arizona (including the Phoenix vicinity)

into parts of northern Arizona this afternoon. Large hail and

damaging winds are the primary risks through the late

afternoon/early evening hours.



The severe thunderstorm watch area is approximately along and 115

statute miles east and west of a line from 50 miles north northeast

of Grand Canyon AZ to 35 miles southeast of Gila Bend AZ. For a

complete depiction of the watch see the associated watch outline

update (WOUS64 KWNS WOU2).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A Severe Thunderstorm Watch means conditions are

favorable for 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. Severe thunderstorms can and occasionally do produce

tornadoes.



&&



AVIATION...A few severe thunderstorms with hail surface and aloft to

2 inches. Extreme turbulence and surface wind gusts to 70 knots. A

few cumulonimbi with maximum tops to 500. Mean storm motion vector

21020.



...Guyer

