Wyoming Water Supply Outlook--March 8, 2019

Areas of Extreme Heat and Fire Weather in the Pacific Northwest; Heavy Rain in the West and South-central US

Extreme heat will continue across the Pacific Northwest into midweek before finally waning. Hot temperatures, dry, gusty conditions, and isolated dry thunderstorms will bring critical fire weather. Heavy rain and thunderstorms are expected across portions of the Southwest, the Sierras, and the central/southern Plains. A series of storms will bring heavy rain and strong winds to southern Alaska. Read More >

HIGHLIGHTS:

…Wyoming February 2019 precipitation was 115 to 125 percent of average...

...Current water year precipitation is averaging 100 to 110 percent of normal across Wyoming…

…Mountain snowpack across Wyoming is 105 to 115 percent of median...

…Near normal to slightly above normal snowmelt streamflow volumes are expected across several major basins in Wyoming…

…Total reservoir capacity across Wyoming continues to be 70 to 75 percent by early March…

SYNOPSIS:

February 2019 precipitation totals across Wyoming were 115 to 125 percent of average. Precipitation numbers varied between 250 percent of normal over the Snake and Upper Yellowstone River Drainages (west to northwest Wyoming) to near 50 percent of average over the Tongue River Basin (north central Wyoming). Current water year (October 2018 - February 2019) precipitation across Wyoming was 100 to 110 percent of average.

Mountain snowpack across Wyoming was 105 to 115 percent of median by early March. Snowpack "water" numbers and/or SWEs were the highest across basins in southeast and western Wyoming—varying between 110 to 130 percent of median. SWEs across basins in north central Wyoming were 80 to 100 percent of median.

Near normal to slightly above normal (95 to 105 percent) snowmelt streamflow volumes are expected across several major basins across Wyoming. Above average snowmelt streamflow volumes are expected across the Snake, Shoshone, Upper North Platte and Laramie Watersheds. Several rivers along the Tongue, Powder, and Upper Green Basins are forecasted to have below normal streamflow volumes during the upcoming snowmelt season.

Total reservoir capacity across Wyoming continues to be 70 to 75 percent by early March. Reservoir storages across Wyoming remain above average at 105 to 115 percent for March.

The latest Wyoming water supply outlook graphic: