February Provides Substantial Increases to Colorado Snowpack — NRCS

Here’s the release from the NRCS (Brian Domonkos):

The month of February brought ample precipitation across the state of Colorado with the South Platte basin being the only in the state that received below average monthly precipitation. The mountains of southwest Colorado fared particularly well. The combined San Miguel, Dolores, Animas, and San Juan basins received 196 percent of average precipitation followed by the Upper Rio Grande and the Gunnison at 175 and 151 percent, respectively. This is great news for those basins after last year’s extremely low streamflows led to depleted reservoir storages going into winter. “Recent storms have led to every major basin in Colorado currently holding above normal snowpack. Additionally, statewide the snowpack has already risen to above the normal peak accumulation which commonly occurs the second week in April. This is good news for the summer water supply situation across Colorado.” notes Karl Wetlaufer, Hydrologist and Assistant Supervisor with the NRCS Colorado Snow Survey.

Statewide Basin High/Low graph March 6, 2019 via the NRCS.

Reservoir storage values remain highly variable across the state and the only basins currently holding above average storage levels are the South Platte and combined Yampa, White, and North Platte which are at 102 and 104 percent of normal, respectively. On the low end the combined San Miguel, Dolores, Animas, and San Juan basins have only 58 percent of average followed closely by the Gunnison at 63 percent. Wetlaufer continued, “Both of these basins are holding some of the lowest reservoir levels seen over the last several decades, so the recent snowfall is welcome news in those areas and will help to begin replenishing reservoir storage after the very low streamflows of 2018.”

Following the trend in snowfall, after this last month all major basins in Colorado now have above average water year-to-date precipitation. As of March 1st, all basins had received a very similar amount of precipitation since the beginning of October, relative to normal, in a range between 108 and 114 percent of average.

Streamflow forecasts in Colorado are currently for near to above average summer streamflow and in many areas the forecasts have notably increased over last month. On the high end the Gunnison basin as a whole is forecast to have 109 percent of average streamflow followed closely by the Arkansas and combined San Miguel, Dolores, Animas, and San Juan basins at 106 and 108 percent, respectively. The average of streamflow forecasts in the Upper Colorado basin is 105 percent of normal and 103 percent in the South Platte. On the low end, but still above normal is the combined Yampa and White River basins which are forecast to have 101 percent of normal flows and 104 in the Upper Rio Grande.

For more detailed information about March 1 mountain snowpack refer to the March 1, 2019 Colorado Water Supply Outlook Report. For the most up to date information about Colorado snowpack and water supply related information, refer to the Colorado Snow Survey website.

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