Truro News

Cold spin over the water in Beaver Harbour, N.B.

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Have you ever seen a waters pout? They’ re pretty amazing. Despite the name, a waterspout is not filled with water from the ocean or lake. Instead it reaches down from a cumulus cloud. The water inside a waterspout is formed by condensati­on in the cloud.

If you really want to see one, head to Florida. Waterspout­s occur more frequently in the Florida Keys than anywhere in the world; they get 400 to 500 waterspout­s a year in the stretch between Marathon to just past Key West.

Gloria didn’t have to go that far to see the one she photograph­ed last weekend. Believe it or not, she spotted a winter waterspout right here in Atlantic Canada, in Beaver Harbour, N.B.

Isn’t it too cold for this in January?

The key to waterspout­s forming is not simply the surface temperatur­e, but the temperatur­e difference between air near the water’s surface and the air a thousand metres or so above the surface.

When deep, cold air spills over a relatively warm body of water, the difference between the cold air above and the not-as-cold air near the water surface leads to instabilit­y – air that wants to rise, forming clouds.

If there’s enough spin from a weak wind shift over the water, the rising air converging from different directions can tighten the rotation into a waterspout.

Of course, for this to occur in mid-winter, you also need a mostly ice-free body of water; otherwise, the flux of relatively warm, humid air from the lake, or river won’t occur.

Most fair- weather, or nonsuper cell waterspout­s remain over water… so they’re pretty to watch, and not dangerous.

Cindy Day is Saltwire Network’s Chief Meteorolog­ist.

 ??  ?? Steam rising off the water on a cold January day ... not uncommon. A winter waterspout ... priceless. Gloria Nickerson-brown spotted the spout last weekend in Beaver Harbour, N.B.
Steam rising off the water on a cold January day ... not uncommon. A winter waterspout ... priceless. Gloria Nickerson-brown spotted the spout last weekend in Beaver Harbour, N.B.
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