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e e Glell Call1"oll Dam - Lake Powell Operations: Releases from Glen Canyon Dam the last two days of:Ylay are being moderately increased from the original May release schedule. Releases on ylay 30 and May 31 will vary from a low of about 9,000 cfs to a high of about 15,000 cfs. This is an increase of about 15 percent. Releases from Glen Canyon Dam in June will average about 14,100 cubic feet per second (cfs) with a total of 840,000 acre-feet scheduled to be released. On Mondays through Fridays in June, daily t1ucruations due to load following will likely vary bet\veen a low of about 10,160 cfs (during late evening and early morning off-peak hours) to a high of about 18,160 cfs (during late afternoon and early evening on-peak hours). On Saturdays, releases will likely vary bet\veen a low of about 10,160 cfs during off-peak hours to a high of about 16,500 cfs during on-peak hours. On Sundays, releases \\-illlikely be steady throughout the day at 10,160 cfs. July and August releases \vill be moderately higher than June. A total of900,000 acre-feet is scheduled to be released in July and August of2003, which averages out to 14,600 cfs. Because of the draw dO\\-n condition of Lake Powell, releases from Lake Powell in water year 2003 are being scheduled to meet the minimum objective release of 8.23 million acre-feet. This is consistent with the requirements of the 1970 Criteria for Coordinated Long-Range Operation of Colorado River Reservoirs. Basin Hvdrol02S: Record breaking high temperatures have persisted over the Colorado River basin in the latter part of May. This very warm weather has resulted in substantial late May snowmelt and runoff. especially in the Yampa River basin and the headwaters drainages of the Colorado River. Some streamflow gages are even recording record high flows for this time of year (the Eagle River in Colorado for example). Unfortunately, the remaining snow in the basin is disappearing fast, and these healthy river flows will not persist. Cnless there is significant monsoonal activity this summer, river flows in the basin in July, August and September of this year will likely be much below normal levels. As ofylay 30, inflow to Lake Powell is 36,000 cfs, about 90 percent of what would normally be seen on this date. Inflow will continue to increase over the next few days, perhaps reaching a peak of 45.000 cfs the first week of June. Even though river flows are quite high in the basin right now, drought conditions continue in the Colorado River Basin. River flows will likely drop dramatically in mid-June. Inflow,volumes are expected to be substantially below average this year with water year 2003 being the 4L'l consecutive year with below average inflow to Lake Powell. The :Ylay mid-month inflow forecast issued by the K ational \V eather Service is calling for 4.3 million acre-feet of unregulated runoff into Lake Powell during the 2003 April through July runoff period. This equates to 54 percent of average. Total unregulated inflow for water year 2003 will likely be about 60 percent of average. A revised inflow forecast will be issued by the ~ational Weather Service the week of June 2. While inflow to Lake Powell picked up considerably the last week of May, inflow was sluggish for most of the month. Total unregulated inflow in May, 2003 will likely be about 1,150,000 acre-feet (50 percent of average). Total inflow to Lake Powell has been significantly below average throughout 2003. Unregulated inflow in January, February, March, and April was 58, 62, 62, and 42 percent of average, respectively.