twisters

A twister is a colloquial term for a tornado, a violently rotating column of air that extends from a cumulonimbus cloud to the ground. Tornadoes are capable of extreme wind speeds and can cause localized, severe damage along a narrow path.

Most tornadoes form from severe thunderstorms called supercells, which contain a rotating updraft known as a mesocyclone. Wind shear and atmospheric instability tilt and rotate air, and under suitable conditions a funnel cloud forms; when it makes contact with the ground, a tornado is born. Some tornadoes involve multiple vortices that rotate around a common center.

Tornadoes are classified by the Enhanced Fujita scale, rating from EF0 to EF5 based on observed damage and inferred wind speeds. They vary in width from a few meters to over a kilometer and can travel from several kilometers to hundreds of kilometers, lasting from seconds to over an hour.

Detection and warning rely on weather radar, especially Doppler radar, to identify rotation within storms. National weather services issue tornado watches and warnings to prompt protective action. Public alerts, sirens, and media reporting help disseminate information to at-risk communities.

Impacts include structural damage, vehicle overturning, and debris hazards. Safety guidance emphasizes seeking shelter in a sturdy building, moving to an interior room on the lowest floor, avoiding windows, covering the head, and having a plan and a means to receive alerts.

Geographic distribution is concentrated in the United States, particularly the central region known as Tornado Alley, but tornadoes occur worldwide. Notable outbreaks and individual storms have driven advances in warning systems, building practices, and risk awareness.