Precipitation
Reservoir
Streamflow
The most probable June through September runoff yield forecast is above
average for the basin. The Snake near Moran is expected to yield 671,000
acre-feet (116 percent of normal). Yield from the Snake River above
Palisades Reservoir is estimated to be 2,370,000 acre-feet (130 percent of
normal). The 50 percent chance yield near Heise is expected to be 3,300,000
acre-feet (126 percent of normal). Pacific Creek at Moran is expected to
yield about 123,000 acre-feet (118 percent of average). Greys River above
Palisades Reservoir is estimated to yield 258,000 acre-feet (107 percent of
normal). Salt River near Etna is estimated to have a yield of 250,000 acre-
feet (110 percent of normal).
================================================================================================================================== SNAKE RIVER BASIN 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) ====================================================================|=======================|===================================== SNAKE near Moran (1,2) JUN-SEP 515 622 | 671 116 | 720 827 579 | | SNAKE above Palisades (2) JUN-SEP 2131 2273 | 2370 130 | 2467 2609 1823 | | SNAKE near Heise (2) JUN-SEP 2923 3148 | 3300 126 | 3452 3677 2622 | | PACIFIC CREEK at Moran JUN-SEP 99 113 | 123 118 | 133 147 104 | | GREYS above Palisades JUN-SEP 220 243 | 258 107 | 273 296 241 | | SALT near Etna JUN-SEP 204 231 | 250 110 | 269 296 228 | | ================================================================================================================================== SNAKE RIVER BASIN | SNAKE RIVER BASIN 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 ========================================================================|========================================================= GRASSY LAKE 15.2 13.6 14.9 13.6 | SNAKE above Jackson Lake 5 182 166 | JACKSON LAKE 847.0 646.0 757.7 540.5 | PACIFIC CREEK 2 145 154 | PALISADES 1400.0 723.3 1121.1 1055.0 | GROS VENTRE RIVER 2 135 130 | | HOBACK RIVER 5 247 178 | | GREYS RIVER 3 197 129 | | SALT RIVER 3 391 139 | | SNAKE above Palisades 17 184 145 | ================================================================================================================================== * 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.