Weather Report for May 23, 2015

The sky cleared at sunset and remained photometric throughout the night. It was an extremely cold night for this time of year, with the temperature reaching 37 deg F by morning twilight. The seeing started out at 1.5-2 arcsec. In the last few hours, there were short periods or very poor seeing (>4 arcsec), but at the end of the night, the seeing settled back to around 2 arcsec.