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Section 5: Radar Interpretation
Interpreting images on your radar screen involves as much art as it
does science. If you want to be confident with your radar at night, you
need to practice in daylight. To be ready for fog or a blinding rain
squall, you must practice in fair weather.
Making you an expert radar reader is beyond the scope of this opera-
tion manual. We strongly suggest you seek additional sources of infor-
mation. For a start, the following pages will show you a few basic radar
returns and how to interpret them. See the end of this section for other
information sources that go into much greater detail.
Anti-Rain Clutter (FTC or Fast Time Constant)
The following five figures show how boosting the FTC level can cut
through display clutter caused by rain or snow. Note how these areas of
intense rainfall gradually grow fainter as FTC increases.
Anti-Rain Clutter (FTC) fig. 1. FTC set to zero. In these examples, we
are using a color mode other than default full-color.
WARNING:
Increasing FTC may reduce or eliminate weak echoes,
like those from small vessels. Use only the minimum
amount needed, then check back periodically to see if
the FTC level may be decreased or turned off.
Rain
Rain
