In the fourth season, Captains Strand and Vega, along with the members of the 126 are called into action to a county fair when a “Derecho,” a series of fast-moving group of severe thunderstorms, hit Austin, causing hurricanic and tornadic-force winds, heavy rains, flash floods and a wide path of destruction. And just when they think it couldn’t get worse, an even more rare weather phenomenon, a “Heat Burst,” causing temperatures to go up to 122 degrees Fahrenheit, hits the city. Owen’s newfound passion for motorcycling and the club he joins because of it put him in the path of the FBI, as they investigate dangerous illegal activities the group may be responsible for. Tommy has the potential for a romance when she meets an attractive single father, who also happens to be the new pastor at her church. And as T.K. and Carlos prepare for their wedding, a secret from Carlos’ past may stand in their way to happiness, especially when he investigates the disappearance of a longtime friend.