Weather Report for May 21, 2014

Campaign 61 begins at the Bok Telescope with a productive night. A broken cloud layer finally moved to the east of Kitt Peak during evening twilight and the sky remained clear overhead and to the west all night long. Clouds formed and dissipated all night long just a few miles to the east of the mountain and caused problems in getting photometry for targets in the eastern sky during the last two hours of the night. The seeing started at around 1.5-2 arcsec and was about 1.5 at the end of the night. During the middle portion of the night, the seeing was highly variable and ranged from 1.2 to nearly 3 arcsec.