Upper Bear River Basin (13)
February 1999

Snow
Snow water equivalent (SWE), at snow courses in the Bear River above the Idaho State Line, is 87 percent of average (89 percent of last year). SWE for the Bear River in Utah is estimated to be 79 percent of average; that is about 90 percent of last year at this time. SWE in the Wyoming portion of the Bear River drainage (Smiths and Thomas Forks) is estimated at 91 percent of average (93 percent of last year at this time.). See the Basin Summary of Snow Course Data at the beginning of this report for more detailed information.

Precipitation
Precipitation for the month of January was 104 percent of average for the 3 reporting stations; this is 68 percent of the previous January. The monthly percentages range from 89 to 245 percent. The year-to-date precipitation, for the basin, is 89 percent of average; this is 103 percent of last year's amount. Year to date percentages range from 83 to 114 percent.

Reservoir
Woodruff Narrows reservoir is currently storing 45,000 acre feet. There is no average established for Woodruff Narrows. The total capacity of the reservoir is 57,300 acre-feet.

Streamflow
The 50 percent chance stream flow yields are expected to be below average in the Bear River drainage. The Bear River near the Utah-Wyoming State Line is expected to yield about 99,000 acre feet; that is 79 percent of average for the April through September period. The Thomas Fork drainage is estimated to yield 26,000 acre feet or 72 percent of normal for the April-September period. The 50 percent chance yield for Smiths Fork near Border is about 106,000 acre-feet (90 percent of normal) for the April-September period. The Bear River near Woodruff is expected to yield about 108,000 acre-feet, about 73 percent of normal for the April-July period. 

==================================================================================================================================
                                                      UPPER BEAR RIVER BASIN
                                               Streamflow Forecasts - February 1, 1999
==================================================================================================================================
                                              |  <<====== 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)
====================================================================|=======================|=====================================
SMITHS FK nr Border, WY              APR-SEP        72        91    |      106        90    |       124       157            118
                                                                    |                       |
THOMAS FK nr WY-ID State Line (Disc. APR-SEP      14.1        20    |       26        72    |        33        48             36
                                                                    |                       |
Bear R nr UT-WY State Line           APR-SEP        71        87    |       99        79    |       113       138            126
                                                                    |                       |
BEAR R nr Woodruff, UT               APR-JUL        59        85    |      108        73    |       138       198            149
                                                                    |                       |
==================================================================================================================================
                         UPPER BEAR RIVER BASIN                         |                 UPPER BEAR RIVER BASIN
             Reservoir Storage (1000 AF) - End of January               |        Watershed Snowpack Analysis - February 1, 1999
==================================================================================================================================
                                      Usable |  *** Usable Storage ***  |                            Number     This Year as % of
Reservoir                            Capacity|  This      Last          |   Watershed                  of       =================
                                             |  Year      Year     Avg  |                          Data Sites   Last Yr   Average
========================================================================|=========================================================
WOODRUFF NARROWS                        57.3     45.0     46.0      --- |   UPPER BEAR RIVER in Utah    3        90        79
                                                                        |
                                                                        |   SMITHS & THOMAS FORKS       4        93        91
                                                                        |
                                                                        |   BEAR RIVER abv ID line      7        89        87
                                                                        |
==================================================================================================================================
 * 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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