Streamflow
The following runoff values are for the 50 percent probability during
the June through September forecast period. The estimated yield for
Tongue River near Dayton is 70,000 acre-feet (91 percent of normal).
Water users on the Middle Fork near Barnum should have a yield near
8,250 acre-feet (104 percent of normal). The North Fork of the Powder
near Hazelton should yield about 7,300 acre-feet (122 percent of
normal). The estimated yield for Clear Creek near Buffalo is 32,000
acre-feet (114 percent of average). Rock Creek near Buffalo will
yield about 19,300 acre-feet (115 percent of normal), and Piney Creek
at Kearny should yield about 36,700 acre-feet (115 percent of
average).
================================================================================================================================== POWDER & TONGUE RIVER BASINS Streamflow Forecasts - June 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) ====================================================================|=======================|===================================== TONGUE RIVER nr Dayton (2) JUN-SEP 54 64 | 70 91 | 76 86 77 | | MIDDLE FORK POWDER nr Barnum JUN-SEP 4.99 6.93 | 8.25 104 | 9.57 11.51 7.90 | | NORTH FORK POWDER nr Hazelton JUN-SEP 5.81 6.70 | 7.30 122 | 7.90 8.79 6.00 | | CLEAR CREEK nr Buffalo JUN-SEP 21 28 | 32 114 | 36 43 28 | | ROCK CREEK nr Buffalo JUN-SEP 15.4 17.7 | 19.3 115 | 21 23 16.8 | | PINEY CREEK at Kearny JUN-SEP 28 33 | 37 115 | 40 45 32 | | ================================================================================================================================== POWDER & TONGUE RIVER BASINS | POWDER & TONGUE RIVER BASINS Reservoir Storage (1000 AF) - End of May | Watershed Snowpack Analysis - June 1, 1999 ================================================================================================================================== Usable | *** Usable Storage *** | Number This Year as % of Reservoir Capacity| This Last | Watershed of ================= | Year Year Avg | Data Sites Last Yr Average ========================================================================|========================================================= TONGUE RIVER 68.0 65.0 26.8 48.2 | UPPER TONGUE RIVER 5 855 142 | | GOOSE CREEK 1 0 118 | | CLEAR CREEK 2 2171 167 | | CRAZY WOMAN CREEK 1 0 269 | | UPPER POWDER RIVER 3 0 192 | | POWDER RIVER in WY 5 3214 174 | ================================================================================================================================== * 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.