Garmin AERA 660 Pilot's Manual page 105

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.
A Convective SIGMET is issued for the following conditions: thunderstorms, isolated
severe thunderstorms, embedded thunderstorms, hail at the surface, and tornadoes.
A SIGMET is widespread and must affect or be forecast to affect an area of at least
3,000 square miles. SIGMETs are displayed as a yellow-dashed line.
Map
AIRMET Selected
Feature
Button
TEMPORARY FLIGHT RESTRICTIONS (TFR)
NOTE: Do not rely solely upon data link services to provide Temporary Flight
Restriction TFR information. Always confirm TFR information through official
sources such as Flight Service Stations of Air Traffic Control.
Temporary Flight Restrictions, or TFRs, temporarily restrict all aircraft from entering
the selected airspace unless a waiver has been issued. TFRs are routinely issued for
activities such as sporting events, dignitary visits, military depots, and forest fires. TFRs
are represented as an area highlighted by red (active) or yellow (not yet active).
190-02017-20 Rev. A
Additional AIRMET Data
Garmin aera 660 Pilot's Guide
Hazard Avoidance
89