Picture this: you’re on vacation in the Florida Keys enjoying the warm, humid weather at the beach, when all of a sudden you notice what looks like a tornado on the water. What you have just witnessed is a phenomenon known as a waterspout. Waterspouts typically occur in the tropics and subtropics, but can also occur in other areas such as the Great Lakes. But what exactly is a waterspout?
A waterspout is a column of spinning air, or a vortex, that occurs over water. There are two different categories of waterspouts: tornadic and non-tornadic. Tornadic waterspouts form in the same way as a tornado that would form over land and are associated with severe thunderstorms. The primary difference between a tornado and a tornadic waterspout is that a tornadic waterspout occurs over water. This can refer either to tornadoes that form over water or tornadoes that form over land and then move over water.
Non-tornadic waterspouts are not formed in severe thunderstorms, and are often referred to as fair-weather waterspouts as they are associated with developing cumulus towers. Non-tornadic waterspouts typically move very slowly, if they move at all, since the clouds they are associated with are developing through vertical convective action rather than through the collision of moving frontal boundaries. Non-tornadic waterspouts go through five stages of development. The first is the appearance of a light-colored disk surrounded by a larger, darker colored area on the water. The second stage of development is characterized by a spiral pattern of light and dark bands outside of the dark spot on the water. A swirling ring of sea spray, called a cascade, then develops around the dark spot. As the waterspout continues to develop, it will form a visible funnel that extends between the water’s surface and the dark flat base of the developing cumulus cloud. The final stage of a waterspout’s life cycle occurs when the inflow of warm air into the vortex of the waterspout weakens causing the waterspout to dissipate.
To learn more about various weather education topics, click here!
©2018 Meteorologist Stephanie Edwards