On July 13, 1996, at 1621 hours Pacific daylight time, a Cessna 180, N4740B, collapsed the landing gear during a ground loop while landing on runway 35 at Thermal, California. The aircraft was owned and operated by the pilot and was on a personal cross-country flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft sustained substantial damage. The certificated private pilot and the two passengers onboard were not injured. The flight originated at LaVerne, California, on the day of the accident at 1500 as a flight to Thermal. The pilot reported that while inbound to the airport he attempted to contact the CTAF for an airport advisory but could not raise anyone on the frequency. He then monitored the ATIS from a nearby airport and selected runway 35 on that basis. As he entered the traffic pattern he observed the windsock indicating an east wind about the speed he obtained from the ATIS and configured the aircraft for a crosswind landing. The pilot said the touchdown on the main wheels and the subsequent ground roll was uneventful until he lowered the tail. Just after lowering the tailwheel to the ground a gust of wind from the east pushed the tail to the left. The pilot said he was unable to regain directional control with either rudder or brake application and the aircraft ground looped to the right, collapsing the left main landing gear and bending the left wing.