Quick Synopsis:

Mountain snowpack and associated snow water equivalents (SWEs) across central
through western Wyoming continued to be much above average by the middle of April;
while SWEs across basins in southeastern Wyoming were generally below average.
SWEs at the peak snowmelt runoff elevations (8,500’ – 10.000’) continue to be the
highest across the Wind and the Upper Green Basins at 170 to 190 percent of median.
The Laramie, Upper North Platte, and Little Snake Drainages had SWEs at near
75 to 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, amount of forest canopy
damage, recent burn scars, low elevation snow depths, and likely temperature and
precipitation trends during late spring/early summer.

HIGHLIGHTS:

…High potential for flooding associated with snowmelt is expected over several
basins across the Little and Big Wind Watersheds…

…High potential for flooding associated with snowmelt is expected over several
basins of the Upper Green Basin…

…Moderate to High potential for snowmelt flooding is expected over headwater
basins of the Snake River Drainage (to include the Salt River Drainage)…

…Moderate to High potential for flooding due to snowmelt is expected over
portions of the North and South Forks of the Shoshone River Basin…

…Moderate to High potential for snowmelt flooding is predicted over portions
of the of the Sweetwater River Watershed…

…Moderate potential for flooding associated with snowmelt is also expected
across the upper to middle portions the of the Little and Big Wind Watersheds,
the middle to upper portions of the Upper Green Drainage, the lower and/or
upper potions of the North/South Forks of the Shoshone Basin, the upper
and lower sections of the Upper Bear Watershed, and several basins across
the Snake River Watershed.

…All other headwater basins (Upper North Platte, Laramie, Little Snake, Powder,
and Tongue Basins) across Wyoming can expect a generally Low potential for
flooding due to springtime snowmelt...

This will be the LAST outlook for the 2017 season

Following are several SNOTEL graphs as of April 20
comparing normal vs current levels of snow water
content and total precipitation since Oct, 1 2016.