Tue, 02/19/2013 - 10:00pm

Holly S. Edwards

Window frost, also called fern frost and ice flowers, forms on the inside of a single-pane storm window. Opening the inside window to take a clear photo causes the frost to melt, so one has to be quick with the camera to capture the beauty. (Photo by Holly S. Edwards)

(Photo by Holly S. Edwards)

CAMDEN — Window frost can be beautiful, and amazing. Especially when the morning sun casts gold or pink through it, and when it's viewed close up.

Frost is a light deposit of small, thin crystals of ice that form on cold objects, when water vapor changes directly into a solid.

Window frost forms when a glass pane is exposed to very cold air on the outside, and moist air on the inside. If the pane is not a good insulator, water vapor condenses on the glass and forms patterns. These patterns are called fern frost or ice flowers.

Frost pattern formation is affected by the glass' surface features, including imperfections, scratches and dust.

Too much moisture on the inside of the window causes the water to first condense in small droplets and then freeze into clear ice. To achieve fern frost, the humidity needs to be moderate, and just the right amount.

Editorial Director Holly S. Edwards can be reached by email at hollyedwards@penbaypilot.com or by calling 207-706-6655.