National Weather Service United States Department of Commerce

Strong winds, colder temperatures, and wintry precipitation expected from the Northeast to New England

A strong cold front and low pressure system will bring strong winds with gusts over 50 mph possible across much of the Middle Atlantic, Northeast, and New England into Sunday night. The strong winds could knock down trees & power lines, and lead to scattered power outages. In addition, the potential exists for snow and ice in portions of New England which could lead to hazardous travel conditions. Read More >

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. 

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Other hydrological information for Wyoming can be found at the NOAA hydrology website:
https://www.weather.gov/riw/local_hydrology

Monthly Wyoming Hydrologic Summary and Graphics:

(updated monthly around the 15th of every month)

https://www.weather.gov/media/riw/hydro/hydro_report.pdf

Wyoming Drought Information Page:

(updated at least once a month)

https://www.weather.gov/riw/drought

Wyoming Graphical Water Supply Outlook:

(updated by the 10th of every month—January-June)

https://www.weather.gov/images/riw/hydro/watersupply.png

Wyoming Average Precipitation by Basin:

 (updated monthly)

https://www.weather.gov/images/riw/hydro/wyomingprecip.png

Wyoming Spring Snowmelt Runoff Flood Potential Graphic:

(updated around the 20th of the month---February-April—sometimes May)

https://www.weather.gov/images/riw/hydro/floodoutlook.png

Current and Forecast Wyoming Streamflows and/or River Stages:

https://water.weather.gov/ahps2/index.php?wfo=RIW

https://water.weather.gov/ahps2/index.php?wfo=CYS

https://waterdata.usgs.gov/wy/nwis/rt

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The current Wyoming Spring 2017 Snowmelt Runoff Flood Potential Outlook graphic: