Storm Chaser Turns Entrepreneur Weather buff Martin Lisius founded Tempest Tours after years of chasing storms himself.

Entrepreneur: Martin Lisius, founder and president of Arlington, Texas-based Tempest Tours, which conducts storm-chasing expeditions.

"Aha" moment: "We'd been storm-chasers for a long time, and people would ask if they could go with us," Lisius says. So in 2000, he started Tempest Tours, working with a climatologist, a tornado scientist and one van.

Tours, which range from four to 10 days, take off from Arlington, Oklahoma City and Denver from late April to early July (prime tornado season). A schedule with dates and locations, based on climatology predictions, is posted a year in advance at TempestTours.com. The self-funded venture has expanded its staff to 15 and has seen slow but steady growth of about 5 percent over the last three years.