Wyoming Spring 2019 Snowmelt Flood Potential---issued March 18th

Severe Thunderstorm and Heavy Rainfall Threat Tonight; Heat Continues on Tuesday Across the Eastern U.S.

Severe weather and flash flooding threats continue across the Central Plains and Midwest into tonight. Very large hail, strong tornadoes and damaging winds are expected. An early season heat wave will continue to challenge temperature records across the eastern U.S. through Wednesday. Read More >

QUICK SYNOPSIS:

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

HIGHLIGHTS:

…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 Laramie Watershed (near Laramie)…

… Moderate potential for flooding due to snowmelt is also expected over a few tributary basins along the Snake River Drainage…

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

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