At the risk of nickel-and-diming you with bad forecast news, today’s Bureau of Reclamation mid-month report is bad forecast news.

April-July flow into Lake Powell is now forecast to be just 3.4 million acre feet, 47 percent of average (pdf). That’s down from 3.75 maf (52 percent) just two weeks ago. Runoff for the full water year (Oct. 1 – Sept. 3) is now forecast at 63 percent, down for 67 percent two weeks ago.

April hasn’t been super warm, but it has been very dry:

April precipitation anomalies, courtesy PRISM

April temperature anomalies

Data courtesy PRISM Climate Group.

What does this mean for Colorado River water users? It decreases the possibility that there will be water available in Lake Powell to release extra supplies for downstream states, which increases the near term odds of a formal shortage declaration sooner (potentially as soon as 2016) rather than later. More here on who will be impacted by shortage.