@USDA_NRCS: Low Persistent #Snowpack

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

The beginning of April typically marks the turning point in the year when snowpack across the majority of the state begins to runoff from the mountains of Colorado. With each day, increased temperatures and solar radiation warm the snowpack melting the shallower, often lower elevation snowpacks first, and progressively impacting higher elevations. Gradually, snowmelt is now starting to ramp up in the southern mountains such as the San Juan Range and Sangre De Cristo mountains. “No considerable basin-wide snowpack losses have yet been observed,” said Brian Domonkos Colorado Snow Survey Supervisor. He added, “However there were a number of individual low elevation sites which recorded significant snowmelt, a trend which is beginning to spread across much of the lower elevations and to move to some mid-elevation sites.” According to SNOTEL and snow course data from April 1, Colorado snowpack is 68 percent of normal down from 72 percent last month.k

Statewide Basin High/Low graph April 4, 2018 via the NRCS.

Looking back over the course of March, precipitation in the mountains of Colorado was only 65 percent of normal, following the current general weather pattern of poor accumulations in the southern half of the state. The southern river basins are around 50 percent of normal for water year precipitation or slightly better but still below normal, and in the northern half of the state March precipitation ranged from 77 to 90 percent of normal. This drove year-to-date mountain precipitation to fall only slightly by month’s end to 70 percent of normal.

The anticipated result from this general weather trend indicate spring and summer forecasted streamflows will generally be between 30 and 70 percent of normal across the state. More positive exceptions exist in the Colorado River Headwaters and South Platte River basins where a few forecasts extend in the 80 to near 100 percent of normal range. Conversely, a number of forecast locations in the southern half of the state dip below 30 percent of normal. Refer to individual streamflow forecasts for the most specific water resource information for use in decision making. Above normal reservoir storage may provide some help in offsetting the low snowpack, but reservoir outflow is highly dependent on the watershed and specific location therein.

The three-month National Weather Service Climate Prediction Center forecast predicts dry and warm conditions through the spring suggesting little reprieve from the current conditions. More information about April 1st snowpack, mountain precipitation, reservoirs levels and streamflow forecasts can be found in the April 1, 2018 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. Or contact Brian Domonkos – Brian.Domonkos@co.usda.gov – 720-544-2852.

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