Rapid changes in weather
The watch will resume accurate altimeter readings when weather conditions settle.
If experiencing rapidly changing weather, consider calibrating the sensor after conditions have settled.
Extended periods of time in a fixed location
For best accuracy, +/- 50 ft (~15 m), calibrate the pressure sensor to a known elevation on a regular basis.
Moving to and from climate controlled or pressurized environments (indoors to outdoors)
Consider calibrating the sensor while you are outdoors.
Debris blocking sensor port
Fluctuating barometer data or lower/higher than expected altitude may be caused by water, or debris in the sensor port (located between the Start/Stop and Back/Lap buttons).
Clean the sensor port. See Related troubleshooting articles below for instructions.
Clothing covering the sensor port
Fluctuating barometer data or lower/higher than expected altitude may be caused by articles of clothing covering the sensor port.
Make sure the sensor port is not covered.
Select your product to confirm this information applies to you
Understanding How the Barometric Altimeter Sensor Works on a Garmin Outdoor Watch
Your outdoor watch uses a barometric altimeter to determine changes in elevation or identify weather patterns by measuring air pressure. This sophisticated sensor works by detecting subtle shifts in pressure. (To learn more about this and other sensors, see Garmin Technology)
How Your Watch Interprets Pressure Changes: Altimeter Modes
Outdoor watches feature different modes to accurately interpret whether pressure changes are due to elevation shifts or weather fluctuations:
- Auto (Default Setting): The watch actively monitors pressure changes and automatically switches between altimeter mode (for elevation changes) and barometer mode (for weather changes) as needed.
- Altimeter Mode: When locked in this mode, the watch assumes all pressure changes are due to changes in elevation. This setting is ideal for activities with significant vertical movement, such as hiking or trail running.
- Barometer Mode: In this mode, the watch assumes all pressure changes are related to weather and shifts in ambient pressure. This is best for activities where your elevation remains relatively constant, like boating or fishing.
For information on calibrating your altimeter and barometer, refer to your owner's manual, or look up your device in support center and search "troubleshooting the altimeter and barometer".