Little Snake River Basin (10)
June 1997

Snow
Snowfall has been above average across the basin this year. Currently the basin is 163 percent of average for the year and 18 percent ahead of last year at this time. Three of the 6 sites reporting have melted out as of June 1. For more information see Basin Summary of Snow Courses at beginning of this report.

Precipitation
Precipitation across the basin is also above average. The Little Snake River basin water-year-to-date precipitation is currently standing at 115 percent of average (7 percent more than last year). May precipitation figures ran about 13 percent above average for the 5 reporting stations. All sites reported average or above precipitation for the month.

Streamflow forecasts
Stream yield, based on the 50 percent probability, is forecast to be 55 percent above average near Slater and 58 percent above average near Dixon. Near Slater the Little Snake should yield about 240,000 acre feet and near Dixon it should be about 520,000 acre feet. 
==================================================================================================================================
                                                     LITTLE SNAKE RIVER BASIN
                                               Streamflow Forecasts - June 1, 1997
==================================================================================================================================
                                              |  <<====== Drier ======  Future Conditions  =======  Wetter =====>>  |             
                                              |                                                                     |
  Forecast Point                     Forecast |  ==================== Chance Of Exceeding * ======================  |
                                      Period  |    90%       70%    |  50% (Most Probable)  |      30%       10%    |  30-Yr Avg.
                                              | (1000AF)  (1000AF)  |   (1000AF)  (% AVG.)  |    (1000AF)  (1000AF) |    (1000AF)
====================================================================|=======================|=====================================
LITTLE SNAKE R nr Slater             APR-JUL       210       228    |      240       155    |       252       270            155
                                                                    |                       |
LITTLE SNAKE R nr Dixon              APR-JUL       416       478    |      520       158    |       562       624            329
                                                                    |                       |
==================================================================================================================================
                        LITTLE SNAKE RIVER BASIN                        |                LITTLE SNAKE RIVER BASIN
             Reservoir Storage (1000 AF) - End of May                   |        Watershed Snowpack Analysis - June 1, 1997
==================================================================================================================================
                                      Usable |  *** Usable Storage ***  |                            Number     This Year as % of
Reservoir                            Capacity|  This      Last          |   Watershed                  of       =================
                                             |  Year      Year     Avg  |                          Data Sites   Last Yr   Average
========================================================================|=========================================================
                                                                        |   LITTLE SNAKE RIVER          6       118       163
                                                                        |
==================================================================================================================================
 * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the actual volume will exceed the volumes in the table.

The average is computed for the 1961-1990 base period.

(1) - The values listed under the 10% and 90% Chance of Exceeding are actually 5% and 95% exceedance levels.                  
(2) - The value is natural volume - actual volume may be affected by upstream water management.
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