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Significant Snowfall Across Central And Southern Wyoming Today and Tongiht

A winter storm will continue to impact western Wyoming today,becoming stronger as it pulls into central and southern Wyoming, where moderate to locally heavy snow is expected to develop into tonight. Read More >

…Wyoming May precipitation was around 200 percent of average...

...Current water year precipitation is averaging 105 to 115 percent of normal across Wyoming…

…Mountain snowpack across Wyoming increased to 95 to 105 percent of average (above 9000 feet)…

Below normal snowmelt streamflow volumes are still expected across all major basins in Wyoming...

…Wyoming carryover reservoir storages have increased to 115 to 125 percent of average for June…

May precipitation totals across Wyoming were around 200 percent of average. Precipitation numbers varied from nearly 272 percent of average over the Lower Green Drainage (southern Wyoming) to near 120 percent of normal over the Upper Yellowstone Watershed (extreme northwest Wyoming).  Current water year (October 2014 – May 2015) precipitation totals across Wyoming increased to 105 to 115 percent of average.

Mountain snowpack (above 9000 feet) across Wyoming increased to 95 to 105 percent of median by early June.  Snowpack “water” numbers and/or SWEs below 9000 feet were less than 20 percent of median statewide.  SWEs were the highest across the Powder, Wind, Laramie, and Upper Green River Basins ---varying between 115 to 180 percent of median.  SWEs across the Snake, Shoshone, Bighorn, and Upper Bear Watersheds were the lowest at 0 to 60 percent of median.

Below normal (65 to 75 percent) snowmelt streamflow volumes are still expected across all major basins across Wyoming.  Several central and southern basins—the Little Snake, the Green, and the Upper Bear---are forecasted to have well below (< 60%) normal streamflow volumes during the rest of the snowmelt season.

Carryover reservoirs storages across Wyoming continue to be above average (greater than 125 percent) for June. 

The latest Wyoming water supply outlook graphic: