Extended Streamflow Guidance
Issued by NWS
FGUS65 KSTR 071545
COLORADO BASIN RIVER FORECAST CENTER
NATIONAL WEATHER SERVICE SALT LAKE CITY UTAH
SPRING FLOOD POTENTIAL
FOR THE GREEN AND BEAR RIVER BASINS IN WYOMING
JANUARY 7, 2015
The 2015 spring runoff flood potential due to snowmelt is
is not high this time for the Upper Green and Bear River
basins. However, it should be emphasized that it is very
early in the snow accumulation season and conditions could
change before the runoff begins.
December precipitation was near to above average in all basins across
southwest Wyoming with values ranging from 100 to 125 percent of average.
Seasonal precipitation is slightly below average in both the
Upper Green and Bear River basins. January 1st snow water equivalent
is above average in the Upper Green with higher amounts above Fontenelle
reservoir and near normal in the Bear River Basin.
The current volume forecasts for the April through July runoff period
are near average in the Upper Green and the Bear River basins. Above average
forecasts exist for a few points above Fontenelle.
Although spring temperatures affect the pattern of snowmelt runoff and
consequently the magnitude of peak flows, peak flows also roughly correspond
to volumetric flows. It is also important to keep in mind that
an extended period of much above normal temperatures or heavy
rainfall during the melt period can cause or exacerbate flooding problems in any year,
regardless of snowpack conditions.
The spring runoff flood potential will be re-evaluated in early February and an updated
product will be issued at that time.