The pilot was landing the tail wheel-equipped airplane on runway 31R. The pilot stated that during the landing, he encountered a crosswind, the left wingtip touched the runway, and the airplane ground looped. The pilot did not report any mechanical malfunctions. Post accident examination of the airplane revealed damage to the left aileron and a wing rib. Approximately 15 minutes after the accident, the wind was reported from 130 degrees at 4 knots.