Gustnado

A weak, short-lived whirlwind that forms along a thunderstorm’s gust front, usually without connecting to the storm’s rotating updraft.

Thunderstorm gust front: The leading boundary of cool air spreading outward from a thunderstorm’s downdraft. Gustnadoes form along this boundary, where turbulent outflow can generate brief vortices.
Tornado: A violently rotating column of air in contact with the ground and connected to a convective cloud. Unlike a gustnado, a tornado is connected to the storm’s rotating updraft.
Storm spotter: A trained volunteer who observes and reports hazardous weather to forecasters. Spotters distinguish gust-front whirlwinds from tornadoes when reporting rotating debris or damage.
Gustnado damage survey: A field investigation that documents damage patterns and assesses whether a gust-front vortex caused them. Survey evidence helps separate a brief gustnado’s effects from tornado damage or broader outflow winds.
Outflow boundary: A boundary separating thunderstorm-cooled air from the surrounding atmosphere. A gust front is an outflow boundary, and its wind shifts help organize gustnado formation.
Landspout: A tornado that forms from near-ground rotation beneath a growing thunderstorm, often without a pre-existing mesocyclone. Both can form without a mature rotating updraft, but a landspout is a tornado rather than a gust-front vortex.
NEXRAD: The United States network of Doppler weather radars used to detect precipitation and atmospheric motion. Radar can reveal storm structure, but a small gustnado may be too brief or near the ground to resolve.
Dust whirl: A rotating column of air made visible by dust or debris near the ground. A dust whirl along thunderstorm outflow can reveal a gustnado’s circulation.
Wind shear: A change in wind speed or direction across distance or altitude. Sharp wind changes near the gust front can contribute to horizontal rotation that becomes a whirlwind.
Mesocyclone: A rotating updraft within a thunderstorm, typically several kilometers wide and lasting minutes or longer. Gustnadoes usually lack the connection to a mesocyclone that characterizes many supercell tornadoes.

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