The following conditions influenced this month's forecasts:

Precipitation:
Seasonal October through February precipitation was 84 percent of average in the upper Bear Basin. February precipitation was 83 percent of average.

Streamflow:
The Bear River at Stewart Dam was 142 percent of average. The Logan River above State Dam recorded 145 percent of average streamflow.

Snowpack:
This years snow remains below average. The current snow water equivalent for the Bear Basin is 78 percent of average. As of water year 2012 the CBRFC has re-calculated all snow stations to reflect the new 30 year average from 1981-2010.


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

Soil Moisture:
Modeled Soil Moisture, click on map to zoom. Modeled soil moisture states indicate above average moisture conditions as of February 1st. This is a contributor to the above average baseflows in the Bear River Basin.

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

Forecast Summary:
The current Bear River volume forecast range from much below average to below average. April through July seasonal volume forecast range from 64 to 84 percent of average with a median volume of 71 percent of average. The above average soil moisture and slightly higher than average baseflow conditions are resulting in higher forecast than one might expect due to snow conditions only.

The following conditions influenced this month's forecasts:

Precipitation:
Seasonal October through February precipitation is 76 percent of average. February precipitation was 74 percent of average.

Streamflow:
The Weber at Oakley gage was estimated to be 112 percent of average. The inflow to Rockport Reservoir was 100 percent of average.

Snowpack:
This years snow remains below average. The current snow water equivalent index is 69 percent of average.. As of water year 2012 the CBRFC has re-calculated all snow stations to reflect the new 30 year average from 1981-2010.

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

Soil Moisture:
Modeled Soil Moisture, click on map to zoom. Modeled soil moisture states indicate above average moisture conditions as of February 1st. This is a contributor to the above average baseflows in the Weber River Basin.

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

Forecast Summary:
The April though July volume forecast for the Weber Basin are currently much below to below average. April through July seasonal volume forecasts range between 59 and 70 percent of average with a median forecast volume of 63 percent of average. Overall this represents a decrease in the median from last month. The above average soil moisture and slightly higher than average baseflow conditions are resulting in higher forecast than one might expect due to snow conditions only.

The following conditions influenced this month's forecasts:

Precipitation:
Seasonal October through February precipitation was near 75 percent of average. February precipitation was 76 percent of average.

Streamflow:
February streamflow for City Creek near Salt Lake City was 85 percent of average. Big Cottonwood Creek nr Salt Lake City was 74 percent of average.

Snowpack:
This year's snow remains below average. The current indexed snow water equivalent is 72 percent of average. As of water year 2012 the CBRFC has re-calculated all snow stations to reflect the new 30 year average from 1981-2010.

Six Creeks Headwaters Basins Snow Plot.

Big and Little Cottonwood Canyons Snow Plot.

Soil Moisture:
Modeled Soil Moisture, click on map to zoom. Modeled soil moisture states indicate mostly above average mositure conditions as of February 1st. Although flows are dropping in the Six Creeks basin, above average soil moistures have been influencing baseflows through the fall and February was the first month that they dropped to near average.

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

Forecast Summary:
The current Six Creeks streamflow volume forecasts remain much below to below average. April through July seasonal volume forecasts range between 62 to 79 percent of average with a median forecast of 66 percent of average. The above average soil moisture and higher than average current baseflow conditions are resulting in slightly higher forecast than one might expect due to current snow conditions only.

The following conditions influenced this month's forecasts:

Precipitation:
Seasonal October thought February seasonal precipitation was 77 percent of average. February precipitation was 97 percent of average.

Streamflow:
Streamflows for the Provo at Woodland were 103 percent of average 106 percent of median, holding steady from last month. Unregulated inflow to Utah Lake was recorded at 87 percent of average which represents a significant drop from the previous month presumably from the lack of snow and precipitation at lower elevations.

Snowpack:
This year's snow as of February 1 remains below average. Current snow water equivalent are 67 percent of average.. As of water year 2012 the CBRFC has re-calculated all snow stations to reflect the new 30 year average from 1981-2010.

Provo River, Utah Lake Drainage Snow Plot.

Soil Moisture:
Modeled Soil Moisture, click on map to zoom. Modeled soil moisture states indicate mostly average to above average conditions as of February 1st. This is a contributor to the current baseflows conditions in the Provo and Utah Lake forecast.

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

Forecast Summary:
The current February forecast for Utah Lake's April through July volumetric forecast dropped slightly as did precipitation and snow as a percent of average. April through July seasonal volume forecasts range between 57 and 66 percent of average with a median forecast volume of 61 percent of average. The above average soil moisture and higher than average current baseflow conditions are resulting in higher forecast than one might expect due to current snow conditions only.

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