Originally Posted by
Seattle Forrest
If the weather changes while you ride or it's windy, your barometer drifts slightly out of calibration. Also barometers are less accurate when in the cold. And when they've been moved thousands of feet up or down. These are reasons to re-calibrate a barometer.
yesterday was cool and windy. ~40F with 15 to 25 mph winds and I was out right after it rained.
I have used this 510 at much colder temps (down to -20F) - typically it appears accurate. However, at these low temps the Garmin does like to read much colder temps than the weather reports.