Freezing Fog Coats Parts Of Denver Area With Rime Ice

DENVER (CBS4) - A large, complex and slow-moving storm system produced areas of dense fog along parts of Colorado's Front Range Thursday morning. Fog is simply a cloud with a base that is touching the ground.

Because temperatures were below freezing supercooled liquid water droplets inside the cloud froze on contact with vertical surfaces such as trees, fences, light poles and signs. Light drizzle, mist and flurries inside the cloud also froze onto surfaces such as less traveled roads, sidewalks, bridges, overpasses and interstate on/off ramps.

In addition to sometimes being a problem on the ground, rime ice can also be a problem in the air if an airplane is flying through clouds with a lot of supercooled water inside. Those cloud droplets can freeze on contact with an airplane's wing, causing it to lose lift.