Snowpack off to good start with SE Utah at 190% of normal

Water flows at the Mill Creek trailhead. The Utah Snow Survey holds promise of another good year for water supply if storms continue through February and March. Photo by Doug McMurdo

Snowpack in Utah got off to a good start for the second year in a row, according to Jordan Clayton, a supervisor and data collection officer for the U.S. Department of Agriculture’s Natural Resource Conservation Service.

Clayton in an email said the Utah Snow Survey show that snow water equivalent was 129% of normal statewide, with all major basins above 100 percent. Southern Utah is pulling up the curve. Southwestern Utah is “off to the best start,” said Clayton, at 229 percent, while southeastern Utah isn’t far being at 190% and Escalante at 195 percent.

Southeastern Utah was at 74 percent as of Jan. 1 last year, so the water supply has improved despite a dry summer. Clayton said December in this corner of the state was way above average – 170% – and 137% above normal from October, when the water year began, through December.

Soil moisture is at 33%, compared to 41% in 2018. Reservoir storage is at 83%, compared to just 13% last year.

The Service uses remote backcountry weather stations that measures snow and transmits data wirelessly, known as snowpack telemetry, or SNOTEL.

Elsewhere, the Bear River and San Pitch watersheds are “faring the worst,” said Clayton, but still at 106% of average.

Clayton said snowpack statewide is about 140% compared to last year. “This is quite impressive when you consider how well our snowpack turned out by the end of last winter, but keep in mind that much of last year’s snowpack came in February and March. Keep your fingers crossed for a repeat performance.”

For that to happen, the state’s snow water equivalent would have to dump an additional 8.5 inches this winter for Utah to have an “average” winter. “So bring on the storms,” said Clayton.

Clayton said the “extremely dry summer” resulted in dry soil moisture levels in the state, roughly 80% of normal, and streamflows at the end of summer were also “rather low.” This means the state will need an above average snowpack to produce average runoff conditions. “We’re off to a good start and the National Weather Service is reporting we can expect an active weather pattern at least through the first three weeks of January.”

Despite the arid summer, reservoirs are still holding more water than usual thanks to a strong 2019 water year. Precipitation is at 95% compared to last year.

Clayton in his report said most of the annual streamflow in the western U.S. originates as snowfall in the mountains. Snowpack is measured and hydrologists estimate the runoff that will occur when it melts.

The snow water equivalent that is measured at SNOTEL sites help with such forecasts, but so does precipitation, antecedent streamflow and even signs of a looming El Niño event are used to give forecasters as much information as possible. Clayton said forecasts can’t be guaranteed because future weather conditions have to be considered, forecasters might not have confidence in the procedure – and the data might not be accurate.