Radar

Radar Horizon

Why we need spotters

Radar beam cannot see most of storm “B”

A

B

Speaker Notes:

• Radar

• Radar Horizon

• Why we need spotters

• Radar beam cannot see most of storm “B”

• B

• A

• Let’s now look as some radar limitations. The radar antenna is angled upward slightly (at 0.5 degrees) on the lowest level scan in order to reduce ground clutter (ground clutter are objects like trees and buildings close to the radar which will produce a “signal” that looks much like precipitation). Therefore, as the radar beam travels away from the radar, it is positioned higher up in the atmosphere. In addition, the curvature of the earth also contributes to this effect. Storms close to the radar can usually be thoroughly sampled from bottom to top. However, the radar beam may only be able to intersect the mid to upper levels of a thunderstorm that is at a greater distance from the radar. Many important features exist in or around the lower levels of thunderstorms. It is possible that the radar will not able to observe these low level features near, or within, a thunderstorm as the radar beam may pass above them. A spotter can be used to compensate for this lack of low level data.