Envirocast® On-Line Feature of the Week -- December 28, 2006

Snow Cover in Colorado

The images in this Envirocast® Bulletin were taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard NASA's Aqua satellite on December 25, 2006. They show the snow cover in Colorado on Christmas.

Snow Cover in Colorado

natural-color image

 

false-color image

The above MODIS images are from December 25, 2006. They show the snow cover in Colorado on Christmas.

 

In visible images (true color), it is sometimes difficult to tell the difference between clouds and snow on the ground (under mostly clear skies). Of course, if you have access to a sequence of visible images, clouds will typically move in time while snow cover won't. On the other hand, while looking at a single visible image, meteorologists can determine whether a blotch of white is snow cover by identifying rivers or lakes, which early in the cold season, are ice- and snow-free and therefore appear as dark fingers amidst white snow cover.  Snow cover ends abruptly at the coastlines.

We also provide false color imagery.  In these false color images, clouds are white, water is black, snow cover is in aqua color and vegetation is green.

 

Zoom-in to the Denver Area

 

Environmental Impacts:

  • Eighteen inches of snow is forecast for the Denver area starting Thursday, December 28, with as much as 2 1/2 feet of snow in the foothills.  If the wind remains as strong as forecast (gusts up to 45mph), it could easily whip the snow into blinding whiteouts by Friday.

  • Last week's storm virtually shut down life along the Front Range, the 170-mile corridor along the foot of the Rockies that's home to 3.8 million people in Denver, Colorado Springs and other cities. It dropped up to 3 1/2 feet of snow in the mountains and 2 feet on the Front Range.

  • Due to the last storm Denver's airport was closed to all flights for 45 hours, leaving about 4,700 people stranded.

  • It was the biggest snowstorm to hit Colorado since a March blizzard in 2003 that shut down the region and killed six.

Supplementary Material:

NASA's AQUA Satellite:

  • Aqua, Latin for water, is a NASA Earth Science satellite mission collecting about the Earth's water cycle, including evaporation from the oceans, water vapor in the atmosphere, clouds, precipitation, soil moisture, sea ice, land ice, and snow cover on the land and ice. The Aqua spacecraft (formally known as EOS-PM) was successfully launched on May 4, 2002 at the Vandenberg Air Force Base (VAFB) in Lompoc, California. t is flying at an altitude of 705 km (438 miles) observing the Earth, and the life expectancy is 6 years. [Aqua's Orbit], [Animation of MODIS Observing the Earth]

  • Aqua passes south to north over the equator in the afternoon, and thus it passes over us at the same local time every day, approximately 1:30 p.m.

Envirocast® Bulletin is a service of StormCenter Communications, Inc. If you are having trouble downloading an image or if you have any questions, please call StormCenter Communications at 410-203-1316.

Envirocast® is a registered trademark of StormCenter Communications, Inc. Envirocast® content is copyright StormCenter Communications, Inc. and is intended to be used solely for those StormCenter customers using the Envirocast software or receiving Envirocast via e-mail delivery directly from StormCenter Communications, Inc. If you are not the intended addressee/recipient, you are hereby notified that any use of, disclosure, copying, distribution, or reliance on the contents of this E-Mail information is strictly prohibited.