Wind: The Invisible Force

Wind rotates around our daily lives unseen. It is the most powerful force behind the world's most catastrophic weather events. But for such a consequential element, few people know where it originates.

To address this, host Richard Hammond participates in a series of risky experiments involving live tornadoes, whirlwinds of fire and a journey into the center of a lab-controlled twister.

The film opens on the Mount Washington summit in New Hampshire, a location that plays host to some of the most extreme and unpredictable weather on the planet. Without the proper protective wear, frostbite can strike in a matter of minutes. Historically, winds in the area have been measured as high as 231 miles per hour. Hammond and his crew brave the risks to demonstrate the impact of comparatively tame wind speeds of 85 miles per hour. This experiment provides valuable lessons in wind patterns, and how various obstacles may redirect those patterns.

From there, we learn why tornadoes, dust devils, and waterspouts are defined by their spiral shape. In the forests of Western Australia, the team illustrates this phenomenon by creating a whirl of flame, which towers high above them when assisted by area winds.

A tornado's destructive force is not determined by how fast it moves along its path; it's the velocity of the winds along its spiral. In Ontario, Canada, the filmmakers attempt to measure the speed of a tornado from the ground level to access the dangers posed to people who fall in their path. Hammond steps inside a manufactured twister powered by 106 fans. This segment shows us how only the lightest objects are taken in by the violent swirl of a cyclone; everything else is spatted out and away from it.

In the final moments of the film, the crew hitches a ride with a professional tornado chaser. Moments like these set the film apart from other documentaries of its kind. The experiments are not entombed in mind-numbing weather theory. For the most part, they are conducted in distinct natural environments, and their components feel like they're verging on the edge of danger.