National Weather Service United States Department of Commerce
Snow Water Equivalent Maps
Snow water equivalent is the depth of water that would cover the ground if the snow cover was in a liquid state. Our river forecasting models use this value, along with temperature and sunshine information, to estimate the amount of snow melt entering the river channels. The actual number is very rarely field checked, but rather estimated from the total snow depth, observed liquid equivalent precipitation, i.e. how much precipitation fell if it was entirely in the form of rain, and the amount of snow melt



Snow Depth and Daily Snowfall Maps

Snow depth is not always a true indicator of the average snow depth over an entire area, but the values are used qualitatively to see if the estimated water equivalents are in need of review or revision.


< 1 in.
1-2 in.
2-3 in.
3-4 in.
4-6 in.
6-8 in.
8-12 in.
12-18 in.
18-24 in.
24-30 in.
30-36 in.
36+ in.
Estimated Snow Coverage

These maps show an estimate of what percentage of the ground is covered by snow.

MARFC Snow Data File (csv)
National Operational Hydrologic Remote Sensing Center Estimate

Additional snow information can be found at the National Operational Hydrologic Remote Sensing Center