Ron Abramovich surveys the March snowpack
March snowpack levels vary widely across state
Boise – Hydrologists from the Natural Resources Conservation Service used the term “March Madness” to describe the results from the latest snow survey which shows a wide range of precipitation levels and snowpack amounts across Idaho. During March, storm after storm moved through central and northern Idaho but left parts of southern Idaho dry.
“Diverse conditions would be an understatement to describe the present snowpack situation in Idaho,” said Jeff Anderson, NRCS Hydrologist in Boise. “Since March 1, we’ve measured one of the greatest one-month changes in snowpack on record.”
According to snow survey and Snow Telemetry (SNOTEL) measurements, the snowpack either increased or decreased depending on the area. Warm weather melted some of the low and mid elevation snowpack in the southern Idaho basins of Bear, Blackfoot, Bruneau, Owyhee, and Portneuf decreasing the snowpack up to 22 percent. With little March snowfall across southern Idaho many of those basins have snowpacks in the dismal range of 40 to 60% of normal.
Many areas north of the Snake River Plain received above average precipitation and snowpacks increased up to 34 percent. March storms left the Panhandle snowpack at about 120% of normal. Snowpacks in the middle of Idaho range from 80 to 110% of normal. Streamflow forecasts rose due to the increased snowpack.
The abundant carry over water stored in Idaho reservoirs may be a problem in some areas that received abundant March precipitation. Reservoirs in southern Idaho are holding an above normal water supply and should accommodate the lower than normal runoff due to the low snowpack this year.
For more information about snowpack, precipitation, runoff and water supplies for specific basins, please view the complete April 2012 Water Supply Outlook Report online at www.id.nrcs.usda.gov/snow and click on the ‘Water Supply’ link.
NRCS conducts snow surveys at the end of each month from December through May to make snow runoff predictions and water supply forecasts used in managing Idaho’s water resources.