Weather Report for May 14, 2013

What started out as a clear evening similar to the previous two nights turned into a much different beast. After observing for nearly 3 hours in pristine conditions, small clouds formed and dissipated on time scales of minutes for the following 3 hours. Good progress was made during this period, although photometry for several objects had to be abandoned. Then, at about 0245 local time the cloud cover became more uniform and for safety it was decided to close the dome to wait and see what develops. At 0315 it rained for about 10 minutes, abruptly ending the night. It was not a lost night, however, as nearly 10 blazars were successfully observed. The seeing started out at about 1.7 arcsec, but was over 3 arcsec at the time of the dome closure.