Observing the Winter Weather

The natural world is full of wonderful examples of a wide variety of types of precipitation, and during the winter in Rocky Mountain National Park, most of it is frozen. We appreciate the beauty, but often don't know the names or understand the processes that form the different types of precipitation we see. Three of the common types of frozen precipitation are rime, glaze ice, and snow.

The National Weater Service defines rime as "tiny balls of ice that form when tiny drops of water (usually not precipitation) freeze on contact with the surface." Rime is milky colored and in the form of crystals. It makes the surfaces it covers look sugar-coated. It is lightly frozen to surfaces and requires a bit of effort to dust off surfaces to which it clings. It is often deposited as a result of an ice fog - a fog that occurs at below-freezing temperatures.

The definition for glaze ice is "a layer or coating of ice that is generally smooth and clear, and forms on exposed objects by the freezing of liquid raindrops. " Glaze ice is dense and clings to tree branches and other surfaces with greater tenacity than rime or snow. Glaze ice is frequently deposited as a result of an ice storm.

Snow flakes are "frozen precipitation composed of ice particles in complex hexagonal patterns. Snow forms in cold clouds by the direct transfer of water vapor to ice. " Snow is very familiar to many U.S. residents. It is composed of six-pointed crystals and individual snowfalls can deposit several inches to a few feet of snow at a time on Rocky Mountain National Park. Snow is usually not attached (frozen) to the surface upon which it is deposited, and can be easily brushed off.

All three forms of frozen precipitation can and do occur throughout Rocky Mountain National Park. But no matter what the name or mechanism of formation, frozen precipitation beautifies even the most common scene, and provides us with opportunities to enjoy our natural environment in unique ways.

Last updated: March 31, 2012

Contact the Park

Mailing Address:

1000 US Hwy 36
Estes Park, CO 80517


(970) 586-1206
Through winter, the Information Office is open 8:00 am–4:30 pm Mon–Fri. Recorded Trail Ridge Road status: (970) 586-1222.

Contact Us