Little Snake River Basin (10)
January 1998

Snow
Snowfall has been much below average across the basin this year. Currently the basin is 55 percent of average for the year and 65 percent behind last year at this time. For more information see Basin Summary of Snow Courses at beginning of this report.

Precipitation
Precipitation across the basin is also below average. The Little Snake River basin water-year-to-date precipitation is currently standing at 81 percent of average (47 percent less than last year). December precipitation is about 46 percent below average (20 percent of last year) for the 5 reporting stations. All sites reported below average precipitation for the month.

Streamflow
Stream yield, based on the 50 percent probability, is forecast to be 71 percent of average near Slater and 68 percent of average near Dixon. Near Slater the Little Snake should yield about 110,000 acre feet and near Dixon it should be about 225,000 acre feet. 
==================================================================================================================================
                                                     LITTLE SNAKE RIVER BASIN
                                               Streamflow Forecasts - January 1, 1998
==================================================================================================================================
                                              |  <<====== 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        68        93    |      110        71    |       127       152            155
                                                                    |                       |
LITTLE SNAKE R nr Dixon              APR-JUL       108       178    |      225        68    |       272       342            329
                                                                    |                       |
==================================================================================================================================
                        LITTLE SNAKE RIVER BASIN                        |                LITTLE SNAKE RIVER BASIN
             Reservoir Storage (1000 AF) - End of December              |        Watershed Snowpack Analysis - January 1, 1998
==================================================================================================================================
                                      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        35        55
                                                                        |
==================================================================================================================================
 * 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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