Six years ago, states in the Great Lakes region witnessed an interesting event - an outbreak of 66 waterspouts occurring from Sept. 27 to Oct. 3 of 2003.
This week-long time slot is considered the largest and longest waterspout outbreak in recorded history over the Great Lakes, according to NOAA's Mariners Weather Log. Here is a picture of a waterspout that formed over Lake Ontario.
Waterspouts typically form over the Great Lakes throughout September. The group from 2003 was caused by higher than normal lake temperatures and a mass of cold air that combined to form the spouts. NOAA's Mariners Weather Log contains an in-depth explanation of how this phenomenon occurred, along with graphics and photos of the event.
Here is a photo of several waterspouts that formed over Lake Huron in 1999.
There are two types of waterspouts: tornadic, like the ones that formed over the Great Lakes; and fair weather, like those frequently seen off the coast of South Florida in late spring and early fall.
Tornadic waterspouts are essentially tornadoes that either form on land and travel to the water, or form over the water initially. They are often seen in the presence of severe thunderstorms, as they spiral downwards from the storm clouds, and can cause significant amounts of damage. Lightning, hail and high winds also can accompany tornadic waterspouts, just like an on-land tornado.
The formation process of tornadic waterspouts consists of five steps. First, a dark spot forms on the surface of the water. Next, dark and light bands on the surface begin to spiral outwards from the dark spots. In the third step, a cascade, or ring of sea spray, begins to form around the dark spot. The cascade also contains an eye like those found in hurricanes. Following the cascade stage, the waterspout becomes fully formed, spiraling from the water to the cloud above. Its spray vortex can reach at least several hundred feet into the air. Finally, in the last stage, the warm air being pulled into the vortex begins to weaken, causing the funnel and spray vortex to collapse.
Fair weather spouts are not typically seen with thunderstorms, as they form from the surface of the water and spiral upwards. They form in the morning or late afternoon in periods of calm weather. While fair weather water spouts can reach land, they typically don't have the strength to travel far inland.
The Eye in the Tropics Web site has a series of photos of both fair weather and tornadic waterspouts that occurred in Florida.
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Brittany Stoner
Fox Weather Correspondent
Penn State University, Print Journalism and Spanish
