Weather Report for January 16, 2013

Tonight was a bizarre night. First, it was generally clear, but there was some very light, scattered cirrus at times that came in from the northeast. This is a very strange direction of motion for high clouds. Second, the night was more than 15 deg F warmer than the previous night. This was welcome as the equipment worked better and the dome could be rotated with no trouble. However, the drastic change led to very bad seeing (usually 3 arcsec, with periods of 4-6 arcsec) during the first 3-4 hours and last 2 hours of the night. Only bright targets could be observed at these times. The seeing was more reasonable at about 2 arcsec during the middle portion of the night. Nearly 20 blazars were observed.

The aggressive warm up in the weather is expected to continue over the next few days and we may get above freezing for the first time in 5 days in the coming hours after sunrise.