On August 13, 1999, approximately 1800 mountain daylight time, a Cessna 180H, N7939V, was substantially damaged during landing roll at Gillette-Campbell County Airport, Gillette, Wyoming. The private pilot, the sole occupant on board, was not injured. The airplane was being operated by the owner under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the cross-country personal flight which originated at Havre, Montana. No flight plan was filed. The pilot said he called the tower for airport advisories when he was 10 to 12 miles north of the airport. He was given a straight in to runway 16, but he didn't remember hearing the wind direction or its velocity. He did perform a left cross wind landing, but as he touched the runway the airplane "weather vaned to the left." The subsequent ground loop damaged the right wing tip and dorsal fin. The pilot stated in his written statement that the surface winds were in excess of 30 knots from his left rear. He said the flags at the terminal were flying straight out. The official recorded winds for Gillette-Campbell County Airport at 1755 were clear skies with winds 080 degrees at 10 knots.