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Atmospheric River in the Pacific Northwest and Northern Rockies this Weekend

A Pacific storm and atmospheric river will impact the Pacific Northwest states and northern Rockies this weekend, bringing locally heavy low elevations rain and heavy high elevation snow in the mountains. By Sunday over the Interior Northwest, rain combined with snowmelt will increase the risk of flood hazards. Flood Watches are in effect. Read More >

SYNOPSIS

 

  • Early April snowpack and/or SWEs were above average (105 to 115% of median) across almost all major basins in Wyoming.
  • Above average snow depths across far western Wyoming.
  • Average soil moisture percentages across basins in northeastern Wyoming and portions of the Wind River Basin; Below average soil moisture percentages across southern Wyoming.
  • Widespread pine bark beetle damage (2010 to 2018) across the Upper North Platte, Little Snake, Laramie, and Wind River Basins.
  • No significant precipitation trends during the spring runoff season (May – July). Above average temperatures are expected across central to western Wyoming during the runoff season.

 

HIGHLIGHTS

 

  • Low to Moderate potential for flooding due to spring snowmelt runoff across portions of the Salt River Basin (far western Wyoming) and portions of the Little Laramie River Basin.  All other headwater basins will generally have a Low potential for snowmelt runoff flooding.

Latest Wyoming Spring Flood Potential graphic: