Spring 2015 Snowmelt Flood Potential-issued February 24th

Wyoming Spring 2015 Snowmelt Flood Potential---issued February 24th

Quick Synopsis:

Mountain snowpack and associated snow water equivalents (SWEs) across northern Wyoming were generally above average by late February; while SWEs across southern Wyoming basins were generally below average.  SWEs at the peak snowmelt runoff elevations (8,000’ – 9.500’) were thehighest across the Powder, Bighorn, and Upper Green Basins at 115 to 135percent of median.  The Little Snake and Sweetwater Drainages had SWEs at70 to 75 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 bark beetle kill, low elevation snow depths, and likely temperature and precipitation trends during late spring/early summer.

HIGHLIGHTS:

…Low to Moderate potential for flooding associated with snowmelt is expected across headwater streams along the western Big Horn Mountains. Streams with the highest potential for snowmelt flooding include Medicine Lodge Creek, Ten Sleep Creek (Ten Sleep), and portions of the Nowood River…

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

The next graphical outlook will be issued around the 25^th of March. 

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Other hydrological information for Wyoming can be found at the NOAA hydrology website:
http://www.crh.noaa.gov/riw/?n=cms_hydro

http://www.crh.noaa.gov/riw/?n=snowpack

Monthly Wyoming Hydrologic Summary and Graphics:

(updated monthly around the 15^th of every month)

http://www.crh.noaa.gov/images/riw/hydro/hydro_report.pdf

Wyoming Drought Information Page:

(updated at least once a month)

http://www.crh.noaa.gov/riw/?n=drought

Wyoming Graphical Water Supply Outlook:

(updated by the 15^th of every month—January-June)

http://www.crh.noaa.gov/images/riw/hydro/watersupply.png

Wyoming Average Precipitation by Basin:

 (updated monthly)

http://www.crh.noaa.gov/images/riw/hydro/wyomingprecip.png

Wyoming Spring Snowmelt Runoff Flood Potential Graphic:

(updated around the 25^th of the month---January-May)

http://www.crh.noaa.gov/images/riw/hydro/floodoutlook.png

Current and Forecast Wyoming Streamflows and/or River Stages:

http://water.weather.gov/ahps2/index.php?wfo=riw

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

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The current Wyoming Spring 2015 Snowmelt Runoff Flood Potential Outlook graphic: