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Basin snow pack stands at 90 percent of average
Jan 27, 2013 - By Eric Blom, Staff Writer
Levels at higher elevations are down from last year.
Early indicators of whether this year's precipitation will be better or worse than 2012 are mixed, and much will depend on spring moisture. Snow depths at high elevations are slightly down from last year, but more snow cover in lower elevations could help.
As snow melts in the mountains, it feeds the streams and rivers, eventually filling the irrigation canals and reservoirs on which agriculture depends.
Across the Wind River Basin, the snow pack is about 90 percent of average. At this time in 2012, snow was 107 percent of normal.
The snow varies, however, and depths are up to 119 percent of average at the northern end of the county and down to 50 percent of normal at the southern, said National Weather Service hydrologist Jim Fahey.
The Sweetwater, Green and Big Horn river basins are in similar shape so far this year.
One measurement by the National Resources Conservation Service of snow depth around the Sweetwater River found it stands at 86 percent, but the agency's sensors read it at 110 percent of normal. Overall, 16 percent more moisture has accumulated this year in the southern Fremont County river basin.
The snow pack around the Wind River above Dubois measures 125 percent of 2012 levels, and measurements above Boysen Reservoir stand at the same level as last year.
Levels of frozen precipitation are down near the Little Wind River at 74 percent and are only 85 percent of 2012's by the Popo Agie.
The National Weather Service reports the snow depth in Riverton is at trace amounts. Thin snow cover low down in the basin, around municipalities and in fields will not add a lot of moisture.
That cover could, however, keep the soil from drying in the winter and will protect the soil from blowing away during strong winds, Fahey said.
If it stays through the winter, that moisture will also prime the top layer of soil for spring rains.
The main reason for the drought last year was spring precipitation in the spring was only about a third of normal, Fahey said.
Whether the drought continues will depend more on moisture that falls this spring and the timing of the snow melt more than conditions so far.
"We rely on our spring
precipitation for nearly half of the year's precipitation," he said.
Fahey said wet snow and rain in March, April, May and June will affect the drought more than the drier snow falling in Fremont County in January and February.
Last year's snow pack started melting early, compounding the problem.
Fahey said that with a long, early melt, much of the water soaks into the ground instead of running into streams.
Fahey said this year falls between the El Niņo and La Niņa, making spring weather hard to predict. The chance of large amounts of moisture falling in the spring is about 50 percent, he added.
The National Oceanic and Atmospheric Administration, however, in a Jan. 17 report predicts drought conditions to persist in Fremont County through this spring.
"I just hope 2012 was an anomaly," Fahey said. "I hope we get a lot of precipitation."