Rain Gradients - Honeywell PRIMUS 660 Pilot's Manual

AVOID STEEP RAIN GRADIENTS BY 20 MILES
Figure 5–43 shows steep rain gradients. Refer to the paragraph,
Interpreting Weather Radar Images, in this section, for a detailed
explanation of weather images.
AVOID ALL CRESCENT SHAPED ECHOES BY 20 MILES
A crescent shaped echo, shown in figure 5–44, with its tips pointing
away from the aircraft indicates a storm cell that has attenuated the
radar energy to the point where the entire storm cell is not displayed.
This is especially true if the trailing edge is very crisp and well defined
with what appears to be a steep rain gradient.
When REACT is selected, the area behind the steep rain gradient fills
in with cyan.
A28–1146–111
REV 2
R
PRIMUS 660 Digital Weather Radar System

Rain Gradients

Figure 5–43
AD–51781–R1@
Radar Facts
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