Extended Streamflow Guidance
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1
000
FGUS65 KSTR 032112
ESGUT

National Weather Service
Colorado Basin River Forecast Center
Salt Lake City, Utah
April 3, 2014

                       FLOOD POTENTIAL OUTLOOK
                                UTAH


The 2014 spring runoff flood potential due to snowmelt is not high at this time
for the Great Basin, as well as the Sevier, Virgin, Price/San Rafael, and the
Duchesne River Basins. However, the flooding potential is high for the
mainstem of the Green River in Utah due to above normal snowpack conditions
in the Upper Green and Yampa River basins and upstream reservoir operations.

Current snowpack conditions in the above basins are below average, except in
portions of the Great Basin.  Current snowpack conditions as a percent of
median are:

Virgin River Basin               55%
Sevier River Basin               80%
Price/San Rafael River Basin     85%
Duchesne River Basin             90%
Great Basin
 --Bear River Basin              115%
 --Weber River Basin             110%
 --Six Creeks Basin               90%
 --Utah Lake                      85%

Currently, the following sites are forecast to peak at or above the bankfull
flow at the given exceedance level:

Bear River near UT/WY State Line10%
Logan River above State Dam near Logan  10%
Weber River near Oakley                 10%
Provo River near Woodland               25%

The following sites are forecast to peak at or above flood stage at the
given exceedance level:

Green River near Jensen25%


Specific forecast procedures and flood flow levels do not exist for all streams.
Given current snowpack conditions throughout the state, slightly above average
peaks may be anticipated in the Bear and Weber River Basin areas, while below
average to near average peaks may be anticipated throughout the rest of the
state.

Current volume forecasts for the April through July runoff period are below
average to near average for much of the state.  In particular, volume forecasts
in the southern portion of the state are well below average.

It should be emphasized that snow accumulation conditions could change
significantly before runoff begins. 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.

A list of specific spring peak flow forecasts are available at:
http://www.cbrfc.noaa.gov/rmap/peak/peaklist.php

A map of the current spring peak flow forecasts is available at:
http://www.cbrfc.noaa.gov/gmap/gmapbeta.php?interface=peak


CBRFC/W.P. Miller, A.Nielson, T. Cox

NNNN
$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.