Category 7: The End of the World

Across the world an unprecedented Category 6 storm descends. Violent winds, hurricane-level pressure and unprecedented "tornado alleys" develop across two continents. For years, scientists have been expounding theories - and warnings - of global-warming effects. It's disaster Code Yellow, as the "storm on steroids" is only just beginning to rend the earth.

The warming effect is creating new regions of extreme weather, but something else is triggering it; something that when combined with record-breaking heat waves creates explosions in the sky. With time running out, discredited scientist Faith Clavell, teams up with storm chaser Tornado Tommy and Judith to discover the trigger.