When operating in precipitation mode, a volume scan takes 5-6 minutes. Depending on whether the radar is operating in clear air mode or precipitation mode, each volume scan takes a different amount of time. Collectively these tilts make up what is called a volume scan. It takes a certain amount of time to rotate the antenna and collect data for all the different tilts. There can still be a lot of weather happening in that lowest few thousand feet beneath the beam, even for the lowest tilt.Ĭollecting radar data is not an instantaneous process for. But keep in mind, even the lowest tilt can be sampling at thousands of feet above the ground depending on the distance from the radar. For most purposes, the casual user will want to stick with tilt 1, which is closest to the ground. But because of the steeper angle, those products can be a little more difficult to interpret. Meteorologists use the higher tilts to get an idea of the vertical structure of a storm. The curvature of the Earth also comes into play, so even if there were no tilt to the radar beam whatsoever, it is looking higher above the ground the further it gets away from the radar. Because of the steeper angle, that effect is more pronounced in the higher tilts. With any tilt, the farther the beam gets from the radar the higher it is looking in the air. Higher tilts allow you to see higher levels of the storm structure. The highest angle (tilt 4) is between 3 and 4 degrees from horizontal. The lowest angle (tilt 1) is about 0.5 degrees for most radars. The radar beam is sent into the air at varying angles, or tilts, from the horizon. This section provides a little more information about how they work as well as resources for learning about them in more detail. Weather radars are complex scientific equipment subject to physical and economical limitations.

Radarscope online