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Gustnado! God Bless You...(cue the laughter)

Other Weather Phenomena Associated With Violently Rotating Columns of Air

Gustnado?

A gustnado is a violently rotating vortex in contact with the ground, and for this reason it is like a tornado. Although similar to a tornado, a gustnado is given a special name because it develops in a different way than a classic super cell tornado. A super cell tornado forms from a long lasting and rotating thunderstorm called a super cell. However, a gustnado occurs on a gust front. A gust front is the leading edge of gusty winds that are produced from downdraft winds in a thunderstorm.

Here's what happens; Downdraft winds come crashing down towards earth out of a thunderstorm. The downdraft winds spread outward upon hitting the land causing a strong rush of wind at the surface. It is along this rush of wind that rotation may develop and a gustnado might form. The gustnado's rotation starts from the surface and spins up.

These gustnadoes may appear at the edge of a squall line as a swirling debris cloud. The leading edge of the squall line may look like the picture below, where the lower cloud is called a "shelf cloud". If you see something like this, you can bet you bottom dollar it's gonna get windy soon. What's happening is the air carrying rain down to the ground in the storm is smacking the earth and spreading outward. This causes the "gust" of air rushing out from the storm.

 

A Gustnado is more of a surface feature and thus will not be connected to the base of the clouds. However, it will be spinning debris and dirt at the surface in typical whirlwind fashion. If it is connected to the base of the clouds, a non-supercell tornado has likely formed. Non-supercell tornadoes are not likely to become violent (F4 or F5).