Here’s the release from the NRCS (Brian Domonkos):
The start to the 2018 water year has been one of the driest on record for Colorado, as recorded by the NRCS SNOTEL network which has been monitoring mountain snowpack and precipitation since the late 1970s. As of January 5th, statewide snow water equivalent (SWE) is at 52 percent of median and there are some very stark differences across the various basins of Colorado. The northern mountains are holding substantially more snow than those of the southern half of the state with the South Platte basin having the most, at 83 percent of median. Alternatively, the combined San Miguel, Dolores, Animas, and San Juan basins are the lowest with a meager 21 percent of normal SWE. Karl Wetlaufer, a Hydrologist with the NRCS Snow Survey Program, notes that “While there is still a lot of winter left we would need to receive well above average precipitation for the rest of the season to achieve a normal peak snow accumulation, especially in southern Colorado”
La Niña conditions are currently present and so far this water year, temperature and precipitation have seemed to display the pattern that is commonly observed across the Rocky Mountains under this climate phenomenon. Wetlaufer explains “This is being observed with the Northern Rockies generally receiving colder temperatures and more precipitation and the Southern Rockies being notably warmer and drier” adding “Montana and Northern Wyoming have had well above normal snowfall for the last several months while much of Arizona and New Mexico have received little to no precipitation at all, with Colorado and Southern Wyoming filling in the north to south gradient”.
From a water supply standpoint the good news for Colorado is that this is the first January in many years where every major river basin in the state is holding above average reservoir storage volumes. These values range from a low of 104 percent of average in the Gunnison to a high of 143 percent in the Arkansas River basin. Statewide reservoir storage currently resides at 115 percent of average.
While it is good to keep in mind that a lot can still change to influence spring and summer streamflow volumes, forecasts generally reflect the trends in snowpack across Colorado, with higher volumes forecasted for the northern basins and lower volumes in the southern parts of the state. That said, at the 50 percent chance of exceedance level there are no streams in the state forecasted to have above average streamflow volumes at this time. For more specific forecast values and water supply prospects view the Colorado Water Supply Outlook Report.
For more detailed and the most up to date information about Colorado snowpack and supporting water supply related information, refer to the Colorado Snow Survey website at:
Or contact Brian Domonkos – Brian.Domonkos@co.usda.gov – 720-544-2852