Weather Report for April 16, 2015


A very windy start to the night with gusts over 30 mph commonplace before midnight. The wind calmed to 5-10 mph during the second half of the night. skies were photometric all night long, but a huge drop in temperature during the night resulted in very poor seeing. The seeing started out at a little under 2 arcsec and progressively worsened. By the end of the night, seeing of 4-5 arcsec was the best that could be coaxed out of a primary mirror that was at least 15 deg F warmer than the freezing temperatures that were reached by morning twilight.