Weather Report for June 30, 2011

A very disappointing night. Big thunderstorms set up to the east during the afternoon, but Mt. Bigelow was spared the excitement and it looked like the night would be clear as all of the action was apparently moving away from the observatory. One target (Mrk421) was observed for polarization and then small, very opaque clouds quickly began forming in all parts of the sky. These irritating puffs were persistent and made observing impossible for the next 1-2 hours. Then, lightning storms began to reform to the north of the observatory and just a little too close for comfort even though the sky often cleared overhead and looked quite good. The impressive lightning displays lasted well past midnight, though no storm formed over the mountain. Conditions were simply too volatile to risk further work. Indeed, a very brief sprinkle of rain graced Mt. Bigelow at about midnight. These were the first rain drops this mountain has seen since early April. Although many of the surrounding areas got much needed rain (for instance, there is no evidence that the large fire to the north is still active after storms hit that general area during the afternoon), the Catalina mountains still await a big rain event to lessen the fire danger. So, little astronomy was accomplished tonight and without a dent made in the local fire danger.