Wyoming Spring 2019 Snowmelt Flood Potential---issued April 17th

Arctic Air Bringing Cold Temperatures to the Eastern Half of the U.S.; Strong Clipper System Wednesday and Thursday

Arctic air will continue below normal temperatures across the eastern half of the U.S. through today. A strengthening clipper storm will track north of the Great Lakes midweek with a widespread snow and gusty to strong winds through the region and into the Northeast U.S. followed by some lake effect snow. Read More >

HIGHLIGHTS:

…Moderate to High potential for snowmelt runoff flooding is forecasted along the lower portions of the Laramie Watershed (near Laramie)…

…Moderate potential for snowmelt runoff flooding is forecasted along the lower portions of the Upper North Platte River Basin (near Saratoga) and along the lower portions of the Little Snake Watershed (near Dixon/Baggs)…

…All other of headwater basins across Wyoming can expect a generally Low potential for flooding due to springtime snowmelt runoff...

QUICK SYNOPSIS:

Mountain snowpack and associated snow water equivalents (SWEs) across most of Wyoming continued to be generally above average by the middle of April. SWEs at the peak snowmelt runoff elevations (8,500’ – 10,000’) were the highest across the Little Snake, Upper North Platte, Laramie, and Snake Basins at 120 to 130 percent of median. The Tongue, Bighorn, and Powder Watersheds had SWEs at 80 to near 90 percent of median at the peak snowmelt runoff elevations.

This outlook is based on various diverse hydrological factors such as snow water equivalents (SWEs) in the mountain snowpack, basin morphology (i.e. how basins respond to snowmelt runoff), antecedent soil moisture, biological/physical factors (bark beetle kill/spruce blight///fire burn scars), low elevation snow depths, and likely temperature and precipitation trends during late spring/early summer.

The current Wyoming Spring 2019 Snowmelt Runoff Flood Potential Outlook graphic: