The following conditions influenced this month's forecasts:

Precipitation:
February precipitation was 119 percent of average.
Seasonal, October through February precipitation was 146 percent of average.

Streamflow:
February streamflows for the Logan River nr Logan were 92 percent of average.

Snowpack:
Snowpacks in the Bear Basin are 136 percent of average.

Upper Bear River Basin Snow Plot.
Bear River Below Woodruff Narrows Reservoir Snow Plot.
Bear River Basin Snow Plot.

Soil Moisture:
Modeled Soil Moisture states were near average to above average for the northern Uinta Mountains heading into the winter.

Climate Forecasts:
Climate forecasts were not factored into the northern Utah forecasts because there is not a strong statistical correlation between El Nino/La Nina conditions and winter precipitation.

Forecast Summary:
Monthly precipitation was above normal this month at 119 percent,seasonal accumulations remained much above average at 146 percent. Current April through July seasonal volume forecasts remain above to much above average and range between 133 and 167 percent of average with a median value of 148 percent.

The following conditions influenced this month's forecasts:

Precipitation:
February precipitation was 120 percent of average. Seasonal October through February precipitation was 150 percent of average.

Streamflow:
February streamflow above Rockport Reservoir was 106 percent of average.

Snowpack:
Snowpacks are currently 130 percent of average.

Weber River Basin Snow Plot.
Upper Weber River Basin Snow Plot.

Soil Moisture:
Modeled Soil Moisture states were mostly above normal in the western Uinta Mountains near the headwaters of the Weber heading into winter.

Climate Forecasts:
Climate forecasts were not factored into the northern Utah forecasts because there is not a strong correlation between El Nino conditions and winter precipitation.

Forecast Summary:
Monthly precipitation was above average at 120 percent. Seasonal accumulations remain much above average at 150 percent. Current April through July seasonal volume forecasts remain much above average, and range between 124 and 155 percent of average with a median value of 140 percent.

The following conditions influenced this month's forecasts:

Precipitation:
February precipitation was 129 percent of average. Seasonal October through February precipitation was 154 percent of average.

Streamflow:
Streamflows for City Creek near Salt Lake City were 95 percent of average.

Snowpack:
Snowpacks are currently 140 percent of average.

Six Creeks River Basin Snow Plot.

Big and Little Cottonwood Canyons Snow Plot.

Soil Moisture:
Modeled Soil Moisture states were near average in the Six Creeks Basin heading into winter.

Climate Forecasts:
Climate forecasts were not factored into the northern Utah forecasts because there is not a strong correlation between El Nino conditions and winter precipitation.

Forecast Summary:
Monthly precipitation was above average this month at 129 percent. Seasonal accumulations remained much above average at 154 pecent. Current April through July seasonal volume forecasts remain above average to much above average, and range between 121 and 152 percent of average with a median value of 130 percent of average.

The following conditions influenced this month's forecasts:

Precipitation:
February precipitation was 116 percent of average. Seasonal October thought February seasonal precipitation is 161 percent of average.

Streamflow:
February streamflow for Spanish Fork nr Castilla were estimated at 136 percent of average. Unregulated inflows to Utah Lake were 148 percent of average. Regulated inflows were 114 percent of average.

Snowpack:
Snowpack are currently 140 percent of average.

Provo River, Utah Lake Basin Snow Plot.

Soil Moisture:
Modeled Soil Moisture states were average to above average heading into the winter.

Climate Forecasts:
Climate forecasts were not factored into the northern Utah forecasts because there is not a strong correlation between El Nino conditions and winter precipitation here.

Forecast Summary:
Monthly precipitation was above average at 116 percent. Seasonal accumulations remained much above average at 150 percent. Current April through July seasonal volume forecasts remain much above average and range between 139 and 164 percent of average with a median value of 146 percent.

Differences between the full period forecasts and the residual forecasts may not exactly equal the actual observed volumes due to rounding conventions (see Definitions section).

10% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 10% chance of being exceeded. Previously referred to as "Reasonable Maximum Forecast".

50% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 50% chance of being exceeded. Previously referred to as "Most Probable Forecast".

90% exceedance forecast: Given the current hydrometeorological conditions, i.e current snowpack, soil moisture and streamflow, the volume that has a 90% chance of being exceeded. Previously referred to as "Reasonable Minimum Forecast".

Acre-Foot (af): The volume equal to one acre covered one foot deep (43,560 cubic feet). See kaf below.

Average: The arithmetic mean. The sum of the values divided by the number of values. Values from 1981-2010 are used for this publication.

Categories: Much Above Average=Greater than 130%, Above Average=111-130%, Near Average=90-110%, Below Average=70-89%, Much Below Average=Less than 70%.

CBRFC: Colorado Basin River Forecast Center.

Forecast Period: The period from April 1 through July 31, unless otherwise noted.

kaf: Thousand Acre-Feet. See Acre-Foot above.

Inflow: The volume of water that flows into a reservoir or lake.

Median: The middle value of an ordered set of values. Half of the values are higher and half of the values are lower. When the set contains an even number of values the median is the average of the two middle numbers.

NOAA: National Oceanic and Atomospheric Administration.

NWS: National Weather Service.

Water supply forecasts take into consideration present hydrometeorological conditions and use average basin temperatures and precipitation for the forecast period. As the forecast season progresses, a greater portion of the future hydrologic and climatic uncertainty becomes known and monthly forecasts become more accurate. For more information on the tools we use, consult Water Supply Forecasting Tools.

Volume forecasts represent adjusted flows; that is, observed flows with upstream water use taken into account. Adjusted flows will closely approximate natural or unimpaired flows. However, not all upstream diversions or impoundments are measured or quantifiable. For specific adjustments used with each forecast point, consult the Guide to Water Supply Forecasting.

The Water Supply Outlook is issued monthly January through May by the Colorado Basin River Forecast Center. It represents a coordinated effort between the National Weather Service, Natural Resources Conservation Service, Bureau of Reclamation, U.S. Geological Survey and local water district managers.

Note: Data used in this report are provisional and are subject to revision.

For more information, or to be included on the mailing list, please contact:

Colorado Basin River Forecast Center
2242 W North Temple
Salt Lake City, UT 84116
(801) 524-5130
www.cbrfc.noaa.gov