State weather experts say the snowpack in the Gunnison River Basin and farther south will likely melt out a month earlier than normal this spring even as snow levels farther north continue to fare better, thanks in part to a recent storm.
"Things are getting better in the areas that are just slightly below normal, and still getting worse in the areas that are way below normal," Peter Goble, climatologist and drought specialist at the Colorado Climate Center, said Tuesday in a webinar on drought conditions.
The update came at a time when snowpack levels in river basins typically reach their peaks and spring runoff begins. Assistant State Climatologist Becky Bolinger said the San Juan River Basin area in southwest Colorado already likely has peaked at 50 percent of normal seasonal peak accumulation, and the Gunnison basin, which is at 58 percent of seasonal median peak, also may have peaked.
"It's probably going to be melted out a month before it normally does just based on how much (snow) there is," she said.
She said the same goes for the San Juan area, while Goble said the Upper Rio Grande Basin is melting out even faster. He said he recently visited southern Colorado and the snowpack looked "heartbreaking" in the San Juan area and "pretty miserable" in the Sangre de Cristo mountains.
Many snow-measurement sites are recording the lowest snowpacks on record in southern Colorado. Sites on Grand Mesa are showing snowpacks at less than half of average, and at or near record low levels.
Meanwhile, the storm that hit northern Colorado watersheds several days ago brought up to 2½ feet of snow, the Colorado Climate Center says. In terms of water content, Bolinger said the storm brought two to three inches of precipitation to some higher-elevation areas and more widespread precipitation ranging from a half-inch to an inch.
Yampa River Basin snowpack is at 80 percent of seasonal peak levels, and the Upper Colorado River Basin in Colorado is at 77 percent of peak. Bolinger hopes to see more accumulation in the Upper Colorado Basin, but she said peak accumulation there usually arrives by mid-April.
Paul Wolyn, with the National Weather Service in Pueblo, said a strong storm system will move through the region late this week, and the north-central mountains in particular could get some good moisture. The storm also will bring cold temperatures to the mountains.
"That will put a halt to the snowmelt in the mountains after the next couple days probably being warmer," he said.
Another storm is in the 10-day forecast, although for now it's expected to benefit mostly northeast Colorado and to the north, Wolyn said.
"It's just nice to see a couple strong systems moving in for the spring," he said.
Colorado's statewide snowpack was at 72 percent of median Tuesday, up from 68 percent at the start of the month. The snowpack is now where it stood March 1 before falling due to March precipitation that was only 65 percent of normal, according to the Natural Resources Conservation Service.
Some streams already are running below average levels, and the NRCS said last week that spring and summer streamflows in Colorado will be between 30 and 70 percent of normal.
It said the Gunnison River at Grand Junction is forecast to have only 33 percent of average streamflow, and the Colorado River at Cameo is expected to flow at 64 percent of average. The Gunnison's flow will be affected by the U.S. Bureau of Reclamation's efforts to hold back as much water as it can in Blue Mesa Reservoir, which it expects will fill to about three-quarters of capacity.
Goble said while it doesn't appear that McPhee Reservoir in southwest Colorado will fill this year, it sounds like farmers in the Four Corners area are being promised their full irrigation allotment. While the reservoir may be drawn down some this year, "we're not in miserable shape there," he said.
Reservoir storage that is at 114 percent of average statewide and is above average even in southwestern Colorado continues to ease the sting of this winter's poor snowfall. Bolinger said she's not hearing a huge concern from water providers this year.
"While I think they're expecting some increased demands they have the capacity to handle that this summer," she said.
She said areas that rely only on streamflow will have more of a concern, as will growers of some dryland crops.
She said water officials will be watching how much reservoir levels can be built up this spring. Southern reservoirs aren't likely to be able to store additional water due to low runoff and increased drawing down due to drought. That will mean that next winter a more normal snowpack will be needed to help those reservoir levels recover.
If next winter is similar to this year, "that's when we're really looking at having to make some hard decisions … and really feeling the effects of drought," she said.