Snowpack problems: Interactive map shows dismal US snow levels

Precious little snow fell in the western United States this past winter, and nearly all of it is already gone, according to the U.S. Department of Agriculture. Thirsty states fighting brutal drought conditions have already received much of what little help they will be getting from melting snow this year.

A snowless mountain along California Highway 88 at Red Lake on April 12, 2015, near South Lake Tahoe, Calif.
George Rose | Getty Images
A snowless mountain along California Highway 88 at Red Lake on April 12, 2015, near South Lake Tahoe, Calif.

The USDA's Natural Resources Conservation Service created an interactive online map that gives snow-related information for the western U.S. SNOTEL is the NRCS's "snow telemetry" service, which measures snowpack levels and related climate information.

The data show that this past winter saw extremely light snowfall all over the western United States, relative to historical averages.

"All along the Cascades and Sierra Nevada are ski courses that never opened, bare mountains and snowless SNOTEL sites where snowpack is measured," writes Spencer Miller of the NRCS. Much of the snow that did fall this year melted during a warmer-than-average March.

A healthy snowpack is not only crucial to the skiing industry. Snow is also an important contributor to water supplies, which are severely depleted in California and in other states battling a multi-year drought.

A foot of newly fallen snow can produce about one and a half inches of water, according to the NRCS. Much of that water flows into major rivers, such as the Colorado River, which provides water to several Western States, including major cities such as Los Angeles, Las Vegas and Phoenix.

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Snowmelt also can be an important contributor to groundwater supplies, which are especially important during dry years.

For the full article and interactive map, click here.