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What is Drought

Snow Drought

The impacts of snow drought are widespread, affecting ecosystems, reservoir levels and operations, water resource management, tourism, and winter recreation.

What Is Snow Drought?

According to the AMS Glossary of Meteorology, snow drought occurs when there is a period of abnormally low snowpack for the time of year in question. Snow drought is described as either dry or warm, depending on whether the drought is a result of below-normal cold-season precipitation (dry) or a lack of snow accumulation despite near-normal precipitation, usually as a result of warm temperatures that cause precipitation to fall as rain rather than snow or an unusually early snowmelt (warm).

Snowpack typically acts as a natural reservoir, providing water throughout the drier summer months. Lack of snowpack storage, or a shift in timing of snowmelt from that reservoir, can be a challenge for drought planning.

The Importance of Snowpack

Snow Drought Impacts

Future Snow Drought


Related Content

Data & Maps | Snow Drought

A collection of tools for accessing observed and forecasted snow data, including snow and river conditions, freezing levels, streamflow and water supply forecasts, ice cover, reservoir storage, and more.

By Sector | Water Utilities

In snow drought events, reduced snowmelt impacts the supply of water to surrounding areas during warm months.

By Sector | Recreation & Tourism

Many local economies and industries rely on snowpack and river flows from snowmelt to support their outdoor industries, such as skiing, rafting, and fishing.

The Great Western Snow Drought of 2015

The winter of 2015 brought unusually warm temperatures to the western United States and serves as a classic example of how warm temperatures can cause snow drought. By April 1, not a single basin in the West was above 86% of median snow water equivalent—and most basins in Washington, Oregon, California, Nevada, Utah, and Arizona were below 40%.

A snow-covered mountain