Weather Report for March 26, 2015


The night started out clear with seeing of just over 2 arcsec. By 2200 local time, fast-moving cirrus moved over the observatory from due north(!) and slowed observations. The almost due north-to-south motion of the cirrus is usually a rare event, but this has been one of the weather features that has often been endured in late 2014 and early 2015. The cirrus was fortunately dissipating as well as swift moving. The sky was completely clear by just after midnight. This clearing coincided with the seeing ballooning to 3-4 arcsec. After about an hour, the seeing settled down to 1.5-2 arcsec for the remainder of the night. Over a dozen blazars were observed.