Precipitation
Reservoir
Streamflow
The fifty percent chance April through July runoff in the upper Green River
basin is forecast below average. Green River at Warren Bridge is expected to
yield about 250,000 acre feet (94 percent of normal). Pine Creek above Fremont
Lake is expected to yield 100,000 acre feet (96 percent of normal). New Fork
River near Big Piney is expected to yield about 350,000 acre feet (91 percent
of normal). The 50 percent chance inflow to Fontenelle Reservoir is about
750,000 acre feet, which is about 88 percent of normal. Big Sandy near Farson
is expected to be about 50,000 acre feet (88 percent of normal).
================================================================================================================================== UPPER GREEN RIVER BASIN Streamflow Forecasts - May 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) ====================================================================|=======================|===================================== GREEN R at Warren Bridge APR-JUL 210 235 | 250 94 | 265 290 266 | | PINE CK abv Fremont Lake APR-JUL 87 97 | 100 96 | 103 113 104 MAY-JUL 85 | 97 96 | 110 101 | | NEW FORK R nr Big Piney APR-JUL 254 333 | 350 91 | 367 447 385 | | FONTENELLE RESERVOIR INFLOW APR-JUL | 750 88 | 849 | | BIG SANDY R nr Farson APR-JUL 36 44 | 50 88 | 56 64 57 | | ================================================================================================================================== UPPER GREEN RIVER BASIN | UPPER GREEN RIVER BASIN Reservoir Storage (1000 AF) - End of April | Watershed Snowpack Analysis - May 1, 1998 ================================================================================================================================== Usable | *** Usable Storage *** | Number This Year as % of Reservoir Capacity| This Last | Watershed of ================= | Year Year Avg | Data Sites Last Yr Average ========================================================================|========================================================= BIG SANDY 38.3 28.7 30.9 23.9 | GREEN above Warren Bridge 4 57 85 | EDEN 11.8 5.2 7.2 5.9 | UPPER GREEN (West Side) 7 56 86 | FLAMING GORGE 3749.0 3190.6 3087.0 --- | NEWFORK RIVER 2 62 83 | FONTENELLE 344.8 131.6 134.1 161.8 | BIG SANDY/EDEN VALLEY 2 61 85 | | GREEN above Fontenelle 13 57 85 | ================================================================================================================================== * 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.