Garmin aera 560 Pilot's Manual page 117

Map
METAR Data (Map)
Feature
Button
The METAR flag color is determined by the information in the METAR text.
VFR (ceiling greater than 3000 feet AGL and visibility greater than 5
miles)
Marginal VFR (ceiling 1000-3000 feet AGL and/or visibility 3-5 miles)
IFR (ceiling 500 to below 1000 feet AGL and/or visibility 1 mile to less
than 3 miles)
Low IFR (ceiling below 500 feet AGL or visibility less than 1 mile)
METAR text does not contain adequate information to determine
flight conditions
AIRMETS
An AIRMET (AIRmen's METeorological Information) can be especially helpful for
pilots of light aircraft that have limited flight capability or instrumentation. An AIRMET
must affect or be forecast to affect an area of at least 3,000 square miles at any one
time. AIRMETs are routinely issued for six-hour periods and are amended as necessary
due to changing weather conditions. AIRMETs are displayed as colored, dashed lines.
SIGMETS
A SIGMET (SIGnificant METeorological Information) advises of weather that is
potentially hazardous to all aircraft. In the contiguous United States, the following
items are covered: severe icing, severe or extreme turbulence, volcanic ash, dust storms,
and sandstorms that lower visibility to less than three statute miles.
190-01117-02 Rev. C Garmin aera 500 Series Pilot's Guide
Hazard Avoidance
Additional METAR Data
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