Snowpack above Middle Park exceeds long-term average despite warm, dry February
March 4, 2009
The USDA Natural Resources Conservation Service (NRCS) Kremmling Field Office snow surveyors Mark Volt and Matt Barnes took the March 1 snow survey measurements during the last days of February, when the monthly precipitation was about 82% of average.
Snowpack in the high-elevation mountains above Middle Park now ranges from 93% to 146% of the 30-year average, with the highest readings on the south side of the valley and the lowest readings on the north side. This is similar to last year when the moisture content was 96% to 133% of average on March 1, although last February was much snowier than this February.
Snow at the lower elevations in Middle Park has undergone a February thaw and does not reflect the above-average snowpack conditions at higher elevation.
Snow density is averaging 28%, which means that for a foot of snow there are 3.3 inches of water.
In Colorado, the snowpack on the western slope exceeds that of the eastern slope, and all major basins are above average except for the South Platte. The highest snowpack, relative to normal, is in the Roaring Fork sub-basin of the Colorado River Basin. Reported readings for the major river basins in Colorado are as follows: The upper Colorado River Basin averages 115%; Gunnison River Basin, 109%; South Platte River Basin, 96%; Yampa River Basin, 112%; White River Basins, 107%; Arkansas River Basin, 109%; Upper Rio Grande Basin, 108%; San Miguel, Dolores, Animas, and San Juan River Basins 107%; and the Laramie and North Platte River Basins, 102% of average for this time of year.
Most of the snow courses around Middle Park have been read since the 1940s. Snow course readings are taken at the end of each month, beginning in January and continuing through April. March is historically the snowiest month, and the April 1 readings are the most critical for predicting runoff and summer water supplies, as most of our high country snowpack peaks around that time.
For further information, including real-time snow and precipitation data for SNOTEL (automated Snow Telemetry) sites, visit http://www.co.nrcs.usda.gov/snow/index.html.