Freezing Rain and Frozen Globes
March 12, 2014
Photographer: Tommy Hornbeck
Summary Author: Tommy Hornbeck
On a cold winter's day an advancing warm front can wedge up and over colder air at the surface creating a layer of warm air between two cold layers. Snow falling from the higher layer melts into raindrops as it passes through the warm layer. When the rain falls into the cold surface layer it becomes supercooled and will instantly freeze when it hits power lines, roads, and trees. This coating is called glaze. It can cause widespread damage if it becomes thick enough to coat the roads, or heavy enough to drag trees and power lines to the ground. Note that if the cold surface layer is greater than about 3,000 ft (914 m) the raindrops will refreeze as sleet before reaching the surface.
If there is a silver lining to this dark cloud it’s the beautiful jewels ice storms create for us to enjoy. The tiny flowers shown above were coated with spheres of ice by a storm in western Missouri. These icy globes acted like lenses serving to highlight and magnify the flowers and sometimes even refracting the intense blue of the clearing skies. Photo taken on December 24, 2013.
Photo details: Nikon D-80 camera; 1/250 second exposure; f-5.6; ISO 100; 85mm lens.