Freezing Fog

Last week I was unable to fly to Edmonton, Alberta due to expected freezing fog. While I stood at the curb at Sky Harbor Airport waiting for a ride back to my house I was confused .

I Googled freezing fog and learned that atmospheric water molecules have a freezing point of 14°F thus remaining in a cloud state 18° lower than the normal freezing point (32°F). However, when it comes into contact with a surface that is less than 32°F (power lines, plants, roads, runways, etc.) the water molecules immediately freeze forming tiny ice crystals. As a desert-rat I am not very familiar with fog, ice and other situations that involve water or freezing temperatures.

I suddenly recall witnessing this phenomenon, but had no idea at the time. I was driving over a pass in Colorado very early on an October morning almost ten years ago. I think it was my first experience driving in fog. I had plenty of experience driving in dust storms with little to no visibility so followed that protocol. As the fog began to lift I saw that I was surrounded by a sparkly, icy landscape. I photographed my mysterious frozen surroundings and discovered that everything had an accumulation of tiny crystals that built upon each other, much like the sugar crystals of Rock Candy.

Picturing a crystal covered runway, I shook my head like I would an Etch-a-sketch, to remove the image from my mind. Thank you, Captain, for not taking chances. I will never again question your wisdom.