Originally Posted by
Looigi
The pressure ports are on the bottom of the unit. If the bottom is reasonably in the clear and horizontal, then it reads static pressure and wind should not affect it significantly. If the unit is tilted so that the ports sees dynamic pressure due to wind, then the altitude reading can be affected. Even with it horizontal, if there is some obstruction that traps the wind under the unit, it can cause elevations errors. Air blowing into the ports will cause an error toward lower elevation.
Interesting. Mine is mounted on a K-edge, right ahead of the handlebar/stem. It is in fairly horizontal position.
Upon additional consideration I think that the rushing winds, generated by the wind gusts, may have created some form of a vacuum which caused the barometric pressure to drop and tricked the Garmin into thinking that I was climbing higher than I actually did.
I will write to Garmin and let them know about this. Maybe they will send me a gift for noticing this glitch.
I wonder if other riders, who ride in wind gust conditions, have noticed a similar result?