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Weekly Weather Event -Week of August 17th

August 21, 2020

On Thursday August 20th, several waterspouts were spotted off the coast of Louisiana. Onlookers captured multiple vortexes in the same area, some clustered together and others making nearly a straight line near an oil rig. No tornado warnings were issued by the National Weather Service, and no significant damage has been reported from the outbreak.

NOAA defines waterspouts as “a whirling column of air and mist” that fall into two categories. Tornadic waterspouts form identically to their on-land counterparts and are produced by severe thunderstorms. Like a normal tornado, waterspouts develop downward from a cloud, reaching the surface of the water as a funnel. These waterspouts are usually accompanied by high winds, choppy seas, large hail, and dangerous lightning.

In contrast, fair weather waterspouts form from the surface of the water and spiral upwards. These typically are formed under flat-bottomed cumulus clouds and are not the products of thunderstorms. They form in light wind conditions, so they are unlikely to move far from their origin point.