Snowpack news

Westwide SNOTEL snow water equivalent as a percent of normal via the NRCS
Westwide SNOTEL snow water equivalent as a percent of normal via the NRCS

From The Denver Post (Scott Willoughby):

In this era of erratic winter weather, the wild swings are not limited to temperature and precipitation. The roller coaster ride also extends to the spring runoff.

Whitewater lovers planning spring floats and fishermen attempting to assess conditions on surrounding rivers have already experienced an ebb and flow worthy of Dramamine merely by tracking the statewide snowpack graphs that predict Colorado’s surface water.

The 2015 calendar year rang in as one of the slowest starts for precipitation since 1992, according to U.S. Natural Resources Conservation Service Snotel data. Colorado mountain precipitation during January fell well below the normal mark, amounting to only 45 percent of the 30-year average.

Recognizing that snowfall is the main ingredient for water in Colorado, heads hung low in the local boating community. But after one of the warmest, driest Januarys any nearby river rat cares to remember, an equally slow start to February ultimately resulted in record snowfall for Denver and respectable totals elsewhere in the northern portions of the state.

By Tuesday, the numbers saw a noticeable bump in each of Colorado’s eight major basins, leading to a statewide snowpack measuring at 91 percent of average. With mountain snow continuing to fall throughout the day, that number almost certainly increased overnight.

Unsurprisingly, to anyone who has spent the past few weeks in or around Denver, the South Platte River Basin leads Colorado’s snowpack statistics at 113 percent of average as of Tuesday. That bodes well for Front Range recreation as South Platte feeder streams such as Clear Creek, Boulder Creek and the Cache la Poudre River are poised to flow at traditional levels, and major reservoirs linked throughout the South Platte corridor are likely to fill.

The excess snowpack in northeast Colorado could also help bolster runoff in the Western Slope’s Colorado River basin now sitting at 98 percent of average because there is likely to be less demand for transmountain diversions, at least in the early season.

The same holds true for the Arkansas River basin, which saw snowpack measuring at 105 percent Tuesday and has enjoyed open water fishing along many stretches for months now. With March, traditionally the state’s snowiest month, just underway, Colorado’s favorite river for both boating and fishing would seem well situated to meet demand by the time snowpack levels typically peak in mid-April.

The state’s only other basin registering above 90 percent of average is the North Platte surrounding Walden with 91 percent snowpack as of Tuesday. Just to its west, the combined Yampa and White river basin measured at only 85 percent, although that number is expected to climb with snowfall in northwest Colorado this week.

Colorado’s upper Rio Grande basin offers a good news/bad news scenario. The bad news is that snowpack in the long-underperforming watershed remains at just 87 percent of historical average. The good news is that is a significant improvement from years past, and even recent weeks, when snowpack has lingered closer to 50 percent of average.

The neighboring Gunnison River Basin also climbed to 87 percent of average snowpack as of Tuesday, with snowfall still accumulating in the surrounding mountains. Despite seeing the largest snowstorm of the winter last weekend, the combined Animas/San Juan/Dolores/San Miguel basin in Colorado’s southwest corner remained the driest in the state, measuring at only 75 percent of average Tuesday.

All things considered, it’s a much better snow and water scenario than we were looking at as recently as two weeks ago. Just don’t be surprised when it all changes again in another few weeks.

From the Natural Resources Conservation Service (Mark Volt) via Sky-Hi Daily News:

USDA Natural Resources Conservation Service (NRCS) Kremmling Field Office snow surveyors Mark Volt and Vance Fulton took the March 1 snow survey measurements during the last days of February, and even with the recent warm weather, the survey shows that the Upper Colorado River Basin is in pretty good shape!

Snowpack in the high elevation mountains above Middle Park now ranges from 78 percent to 128 percent of the 30-year average, with the overall average for Middle Park at 102 percent.

Last year at this time the area was at 141 percent of average. Snow density is averaging 25%, which means that for one foot of snow there is 3.0 inches of water, which is normal for March 1, though lower elevation/valley snowpack appears to be suffering.

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 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.

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