BLOG: Rime ice vs frost - | WBTV Charlotte

BLOG: Rime ice vs frost

(Steve Ohnesorge | WBTV) (Steve Ohnesorge | WBTV)

I thought I would share a great picture from Steve Ohnesorge as our recent surge of cold air blasted into the viewing area. As it arrived in the mountains, it was accompanied by low clouds and fog.  

The tiny water droplets in clouds and fog can exist in temperatures below freezing; they are known as supercooled droplets. The microphysics of how droplets can exist in below-freezing conditions is still not completely understood, but one thing these supercooled droplets all have in common is they didn’t have a seed, or nucleus on which to crystalize.

As they blow along with the wind and come into contact with solid surfaces, the freezing can begin as the ice forms on the trees and branches, usually appearing as a bright white icy buildup. This is what you are seeing in Steve’s picture.

Frost formation is a different process. Much like condensation, frost forms from water vapor in the air (invisible gas) and never passes through a liquid phase as happens with rime ice.  

Condensation occurs when water vapor deposits water droplets on your cold glass of water. When frost forms, that is known as deposition which you commonly see on grass and plants outside in the subfreezing air.  

- Eric Thomas

Copyright 2016 WBTV. All rights reserved. 

Powered by Frankly