Little Snake River Basin
April 1997

Snow
Snowfall has been good across the basin this year. Snow accumulation was below average last month, which lowered the year to date percent of average SWE. Currently the basin is 124 percent of average for the year and 16 percent ahead of last year at this time. All of the reporting sites are above average at this time. 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 116 percent of average (7 percent more than last year). March precipitation figures are very low at all reporting sites. March precipitation was 53 percent below average (64 percent of last year's monthly total).

Streamflow
Stream yield, based on the 50 percent probability, is forecast to be 48 percent above average near Slater and 52 percent above average near Dixon. Near Slater the Little Snake should yield about 230,000 acre feet and near Dixon it should be about 500,000 acre feet. 
==================================================================================================================================
                                                     LITTLE SNAKE RIVER BASIN
                                               Streamflow Forecasts - April 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       195       216    |      230       148    |       244       265            155
                                                                    |                       |
LITTLE SNAKE R nr Dixon              APR-JUL       390       456    |      500       152    |       544       610            329
                                                                    |                       |
==================================================================================================================================
                        LITTLE SNAKE RIVER BASIN                        |                LITTLE SNAKE RIVER BASIN
             Reservoir Storage (1000 AF) - End of March                 |        Watershed Snowpack Analysis - April 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          8       116       124
                                                                        |
==================================================================================================================================
 * 90%, 70%, 30%, and 10% chances of exceeding are the probabilities that the actual flow 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 flow - actual flow may be affected by upstream water management.
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