Radar - Garmin Pilot User's Guide for Android User Manual

Plan

RADAR

Weather radar data is collected from radar sites across the United States, Canada,
and select overseas locations. It is combined into a mosaic for easier display and
analysis.
The radar data displayed is not real-time. The lapsed time between collection,
processing, and dissemination of radar images can be significant and may not reflect
the current radar synopsis. Due to the inherent delays and the relative age of the
data, it should be used for long-range planning purposes only. Never use radar data
to penetrate hazardous weather. Rather, use it in an early-warning capacity for pre-
departure evaluation.
Composite data from radar sites in the United States is shown. This data is
composed of the maximum reflectivity from the individual radar sweeps at different tilt
angles of the radar beam with respect to the ground. The display of the information
is color-coded to indicate the weather severity level. Colors are used to identify the
different echo intensities (reflectivity) measured in dBZ (decibels or Z). "Reflectivity"
(designated by the letter Z) is the amount of transmitted power returned to the radar
receiver. The dBZ values increase as returned signal strength increases. Precipitation
intensity is displayed using colors corresponding to the dBZ values.
RADAR ABNORMALITIES
There are possible abnormalities regarding displayed radar images. Some, but not
all, of those include:
• Ground clutter
• Strobes and spurious radar data
• Sun strobes (when the radar antenna points directly at the sun)
• Military aircraft deploy metallic dust (chaff) which can cause alterations in radar
scans
• Interference from buildings or mountains, which may cause shadows
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Garmin Pilot for Android User's Guide 190-01532-00 Rev. A