Weather Report for September 17, 2009

Photometric, calm night. Seeing was generally good: between 1-1.5 arcsec. A surprisingly strong storm system is sliding by Kitt Peak to the northeast. Lightning can be seen from the Bok telescope along the eastern and northeastern horizon even though the thunderstorms are 150-200 miles away. Forecasters have this system affecting southern Arizona over the next 2 days, but no hint of it yet.