Upper Bear River Basin (13)
January 2000

Snow
Snow water equivalent (SWE), at snow courses in the Bear River above the Idaho state line, is 46 percent of average (63 percent of last year). SWE for the Bear River in Utah is estimated to be 50 percent of average; that is about 81 percent of last year at this time. SWE in the Wyoming portion of the Bear River drainage (Smiths and Thomas Forks) is estimated at 52 percent of average (59 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 December was 57 percent of average for the 2 reporting stations; this is 64 percent of the previous December. The monthly percentages range from 61 to 68 percent of average. The year-to-date precipitation, for the basin, is 41 percent of average; this is 49 percent of last year's amount. Year-to-date percentages range from 38 to 45 percent of average.

Reservoir
No data for Woodruff Narrows reservoir was received this month.

Streamflow
The following 50 percent chance stream flow yields are for the April through September period. Smiths Fork near Border is about 79,000 acre-feet (67 percent of normal), and Thomas Fork drainage near the Idaho-Wyoming state line is estimated to yield 20,000 acre-feet or 56 percent of normal. Bear River near the Utah-Wyoming State Line is expected to yield about 81,000 acre feet; that is 64 percent of average, while Bear River near Woodruff is expected to yield about 92,000 acre-feet, about 60 percent of normal. 

==================================================================================================================================
                                                      UPPER BEAR RIVER BASIN
                                               Streamflow Forecasts - January 1, 2000
==================================================================================================================================
                                              |  <<====== 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        47        64    |       79        67    |        97       132            118
                                                                    |                       |
THOMAS FK nr WY-ID State Line (Disc. APR-SEP       9.6      14.8    |       20        56    |        27        42             36
                                                                    |                       |
Bear R nr UT-WY State Line           APR-SEP        56        70    |       81        64    |        94       117            126
                                                                    |                       |
BEAR R nr Woodruff, UT               APR-SEP        45        69    |       92        60    |       123       187            154
                                                                    |                       |
==================================================================================================================================
                         UPPER BEAR RIVER BASIN                         |                 UPPER BEAR RIVER BASIN
             Reservoir Storage (1000 AF) - End of December              |        Watershed Snowpack Analysis - January 1, 2000
==================================================================================================================================
                                      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     37.5     43.0      --- |   UPPER BEAR RIVER in Utah    3        81        50
                                                                        |
                                                                        |   SMITHS & THOMAS FORKS       3        59        52
                                                                        |
                                                                        |   BEAR RIVER abv ID line      6        63        46
                                                                        |
==================================================================================================================================
 * 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.
(3) - Forecasts produced in cooperation with Alberta Forecasting Staff Canada
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