VAD

One particularly useful product from Doppler Radar is known as a Velocity Azimuth Display, or VAD. The VAD profile shows the change in wind speed and direction with increasing height. The type of thunderstorm that develops and its tornado potential depends strongly on the vertical wind profile. Since the VAD profile is updated every 6 minutes, forecasters can detect subtle changes in the atmosphere's wind structure that makes tornado development more likely. Doppler Radar Velocity Azimuth Display (VAD). (NOAA/NWS)