June 29: Holiday air travel chaos. Extreme heat and smoke impacting millions. Simone Bile’s surprise return. Fireworks safety in the spotlight.

<p>Flight cancelations and delays growing ahead of the holiday weekend. Also, millions of Americans under air quality alert from another round of those Canadian wildfires. Plus, Simone Biles planning to compete later this summer for her first time since the 2020 Tokyo Olympics. And, In-Depth TODAY: Vicky shares some fireworks safety tips ahead of July 4th. </p>