Witnesses say the wind came in under the sides of the tent and pressurized it to lift it up and tear-out the anchor lines. The wind toppled the sound towers and the overstage truss system as well.
Fortunately, the incident occured before there were any audience members present. The show was cancelled and will be reschedule.
TV Interview with injured crew member:
NewsOK web site article: http://www.newsok.com/local-production-crew-talk-about-tent-collapse-at-lucky-star-on-tuesday/article/3474327
Arial footage showing tent site and mangled stage gear:
A walking tour of the stage and mix tower after the event:
This video reveals alot about the original set-up. It shows that the truss bases were not anchored and did not have any ballast weights. The rig was set-up as if it was an indoor show with no regard to the wind that could blow through and topple the gear if the tent was breached.
Anchor your Rigs! Watch the weather! Don't wait for it to hit before you react!