From the US Bureau of Reclamation:
Current runoff projections into Lake Powell are provided by the National Weather Service’s Colorado Basin River Forecast Center and are as follows: Observed unregulated inflow into Lake Powell for the month of December was 0.299 maf or 82 percent of the 30-year average from 1981 to 2010. The forecast for January unregulated inflow into Lake Powell is 0.310 maf or 86 percent of the 30-year average. The forecasted 2018 April through July unregulated inflow is 3.900 maf or 54 percent of average.
In this study, the calendar year 2018 diversion for Metropolitan Water District of Southern California (MWD) is forecasted to be 0.732 maf. The calendar year 2018 diversion for the Central Arizona Project (CAP) is forecasted to be 1.574 maf. Consumptive use for Nevada above Hoover (SNWP Use) is forecasted to be 0.290 maf for calendar year 2018.
Due to changing Lake Mead elevations, Hoover’s generator capacity is adjusted based on estimated effective capacity and plant availability. The estimated effective capacity is based on projected Lake Mead elevations. Unit capacity tests will be performed as the lake elevation changes. This study reflects these changes in the projections.
Hoover, Davis, and Parker historical gross energy figures come from PO&M reports provided by the Lower Colorado Region’s Power Management Office, Bureau of Reclamation, Boulder City, Nevada. Questions regarding these historical energy numbers can be directed to Eric Carty at (702) 293-8129.
Note: John Fleck warns about the “error bars” around a forecast this early in the season.