People on the sound side of Kill Devil Hills got quite the surprise this morning when they looked west and witnessed waterspouts over the Albemarle sound. There are some pretty cool videos already going viral on Facebook. Check out the one posted by Tortuga's Lie on their Facebook page.
So, what exactly is a waterspout? There are actually two answers to that question because there are two different types.
According the American Meteorological Society’s Glossary of Meteorology, the first type is simply any tornado over a body of water. A tornado is a rotating column of air connected to the cloud base and in touch with the ground. A tornado creates a debris cloud as it spins up whatever material is at the surface. When one is over water, the debris cloud is a moisture cloud.
Tornadic waterspouts are relatively rare compared to the second type, and are as dangerous as any other tornado. Boaters should avoid them at all costs. The one near Kill Devil Hills this morning did move over land and cause some damage.
The second type of waterspout is often referred to as a “fair weather waterspout.” Most people will recognize these as the type famous for forming off the Florida Keys, but they also form over the Great Lakes during the late summer to early fall months, as well as in many other parts of the world.
As insinuated by the name, supercell thunderstorms are not required for the formation of fair weather waterspouts. They are formed by a different process as explained in an article from the National Weather Service:
Dr. Joseph Golden distinguishes five stages of waterspout formation:
Dark spot. A prominent circular, light-colored disk appears on the surface of the water, surrounded by a larger dark area of indeterminate shape and with diffused edges.
Spiral pattern. A pattern of light and dark-colored surface bands spiraling out from the dark spot which develops on the water surface.
Spray ring. A dense swirling annulus (ring) of sea spray, called a cascade, appears around the dark spot with what appears to be an eye similar to that seen in hurricanes.
Mature vortex. The waterspout, now visible from water surface to the overhead cloud mass, achieves maximum organization and intensity. Its funnel often appears hollow, with a surrounding shell of turbulent condensate. The spray vortex can rise to a height of several hundred feet or more and often creates a visible wake and an associated wave train as it moves.
Decay. The funnel and spray vortex begin to dissipate as the inflow of warm air into the vortex weakens.
Although this second type is not technically a tornadic storm, it is still dangerous enough that it should be avoided. Waterspouts off the Florida Keys have been well studied and well documented. A simple search of “Florida Keys waterspouts” on Youtube gives over 18,000 results. So, if you want to “ooh” and “ah” over more video and geek out like a true weather fan, there are plenty of options for viewing.