 Impact expected Monday between Matagorda Bay and Corpus Christi, where 10,000 sandbags were handed out Friday in an hour and a half. The village of Surfside Beach issuing a mandatory evacuation for all recreational vehicles and watercraft. Chris Fox for CBS News, Austin. Meantime, millions of Americans are under health threats amid a record-breaking heat wave. Dangerously hot weather is prompting concerns across the country for the most vulnerable, and it's fueling wildfires out west. Our Elise Preston is in Los Angeles.