Tornado Vortex Signature - Display

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It is often visible on the Doppler radar storm relative velocity product as side by side inbound and outbound velocities, a signature known as a velocity couplet or "gate-to-gate" shear. In many cases, the TVS is a strong mesocyclone aloft, not an actual tornado, although the presence of an actual tornado on the ground can occasionally be inferred based on a strong couplet in concert with a debris cloud signature, or through confirmation from storm spotters. When the algorithm is tripped, a TVS icon (typically a triangle representing a vortex) and pertinent information appear. Radar analysis of the velocity couplet as well as the automated TVS are very significant to issuing tornado warnings and can suggest the strength and location of possible tornadoes. Although many tornadoes, especially the stronger ones, coincide with a TVS, many weak EF0-1 tornadoes can and do occur without a TVS, especially if they are not produced from an identified mesocyclone. Likewise, phenomena such as "fair-weather" waterspouts and gustnadoes, though cyclonic and occasionally destructive, do not normally produce a signature identifiable by a TVS.