Early runoff forecast numbers released

If the weather continues along this same pattern until spring, it looks as though we may not have the high water issues on the Big Horn River that we’ve had the past couple of years.

According to the most recent reports from the National Oceanic and Atmospheric Administration (NOAA), below normal snowmelt streamflow volumes are expected across several major basins in Wyoming, including the Wind and Big Horn.

Current water year precipitation is averaging 95 to 105 percent of normal across the state with mountain snowpack at 85 to 95 percent of average.

Wyoming’s reservoirs are averaging 70-75 percent of capacity early in February.

Snowpack water numbers were the highest across basins in southeast Wyoming, varying between 100 and 125 percent of average. Western Wyoming’s basins, however are between 75 and 85 percent of median.

This will mean above average snowmelt streamflow volumes in areas such as the Upper North Platte and Laramie watersheds.

The Bureau of Reclamation recently released its February forecast of the April through July runoff predicted for the Bighorn Basin. The report shows the forecasted April through July inflow to Boysen Reservoir is 450,000 acre feet (af), which is 75 percent of the 30-year average of 603,300 af

Looking at the monthly statistics from NOAA, we see in October, the water forecast showed the Wind River Basin at 82-94 percent of normal, yet in December, that number had dropped to between 59 and 73 percent due to the negative effects our warmer fall had on the snowpack.

As of the middle of February, we’re having just minimal drought conditions here, but that could change dependent on what the spring rains bring. December was abnormally dry for us.

For additional information on Boysen Reservoir, contact Wyoming Area Manager Carlie Ronca at 307-261-5671.