Some light, scattered cirrus at the beginning of the night. Heavier and more widespread cirrus moved in just before midnight. Most attempts at spectrophotometry were abandoned by 2300 local time. Polarimetry continued throughout the night, but faint targets were either impossible to do or much more difficult because of the increasing cloud cover. The seeing was excellent during most of the night at around 1-1.5 arcsec. There were a few brief periods of sub-arcsec seeing.
