Suppose you are sitting in your car, at the trailhead or the base of a ski area, and you know the temperature where you are, but you’re wondering how cold it will be when you get to the top. Do you want to wear that extra layer, or put it in your pack?

TempOnTop is an app to help you with those decisions.

Or you went skiing the other day, and you know it was -10 at the base, and you wonder what the wind chill was on top with a wind of 30 miles per hour. With TempOnTop, you can secure those bragging rights, and even post them directly into Facebook.

To use TempOnTop, simply set the Base Temperature and Elevation using the sliders. Both US and Metric units are displayed, so you can use what’s available to you regardless of where you are. You can then set the Top Elevation, and an estimate of the temperature on top of the mountain will be created. If you would like to know the wind chill factor, then you can set the actual or estimated winds for the base, the top, or both and see the wind chill values and frostbite times. You can also set either the base or the top altitude using the iPhone GPS.

Mountain weather can be serious. This app is meant to help you be more comfortable on the mountain, but is not meant for use in potential survival situations.

For more information about mountain weather calculations, please see the web support page.