What radar signature uses lofted debris to confirm a tornado is occurring?

The radar signature that uses lofted debris to help confirm a tornado is occurring is a tornado debris signature.

A tornado can lift trees, insulation, roofing, vehicles, and other objects high enough for weather radar to detect them. On reflectivity imagery, this may appear as a compact area of unusually high reflectivity, often called a debris ball. Dual-polarization radar adds confidence by identifying the irregular, nonmeteorological targets within the circulation.

Meteorologists look for a debris signature near a strong velocity couplet or tornado vortex signature. It can provide confirmation when the tornado itself is hidden by rain or darkness, but its absence does not rule out a tornado. Weak tornadoes, open terrain, distance from the radar, and a lack of debris can all prevent detection.

Debris signatures are more likely when a tornado crosses a populated or forested area. Their interpretation depends on radar geometry and storm context, so forecasters combine the signal with velocity data, storm structure, and reports from the ground.