Water Supply Outlook for Wyoming May 8 2017

Water Supply Outlook for Wyoming May 8 2017

…Wyoming April 2017 precipitation was 150 to 160 percent of average…
…Current water year precipitation is averaging 140 to 150 percent of normal across Wyoming…
…Mountain snowpack across Wyoming is 125 to 135 percent of median… 
Above to much above normal snowmelt streamflow volumes are still expected across 
most major basins in Wyoming…
…Wyoming reservoir storages are 125 to 135 percent of average for May… 

SYNOPSIS

April precipitation totals across Wyoming were 150 to 160 percent of average. 
Precipitation numbers varied between near 250 percent of normal over the 
Tongue River Drainage (north central Wyoming) to near 110 percent of normal 
over the Lower Green Basin (southwestern Wyoming).  Current water year
 (October 2016 – April 2017) precipitation across Wyoming is averaging 
140 to 150 percent of average.
 
Mountain snowpack across Wyoming was 125 to 135 percent of median by early May.
Snowpack “water” numbers and/or SWEs were the highest across basins in central
Wyoming (Wind, Upper Green, and Sweetwater)—varying between 
190 to near 230 percent of median.  SWEs across basins in southeastern 
Wyoming were 85 to near 100 percent of median.  
 
Above to much above normal (160 to near 175 percent) snowmelt streamflow 
volumes continue to be expected across almost all major basins across Wyoming. 
Well above average (180 to 250%) snowmelt streamflow volumes are still expected 
across the Snake, Wind, Sweetwater, Shoshone, and Upper Green Watersheds.
The Little Snake, Upper North Platte, and Laramie Basins are forecasted to have slightly below to 
slightly above normal streamflow volumes during the upcoming snowmelt season. 
 
Reservoirs storages across Wyoming remained above average at 125 to 135 percent for May.