Hurricanes are huge rotating storms that draw their energy from warm ocean water.

The longer version

Tropical cyclones are heat engines powered by the ocean. Warm water evaporates readily, and when that vapor condenses into cloud it releases the energy it absorbed, warming the surrounding air and driving a rising column that lowers pressure at the surface.

Air spirals inward toward that low pressure, is deflected by the planet's rotation, and organizes into the familiar rotating bands. The system needs water above roughly twenty-six degrees to survive, which is why such storms weaken once they move over land or cooler seas. They also need relatively calm winds aloft, since strong shear tears the rotating structure apart.

Where this entry sits

Clouds, wind, rain, and storms shape daily life in ways that most people barely notice. This collection explains snow, lightning, rainbows, the turning seasons, temperature, the instruments forecasters rely on, and scraps of old weather lore. The full list sits on the Weather and Climate page, where every entry is listed in order.