On May 16, 2004, approximately 0945 mountain daylight time, a Cessna 185A, N1624H, impacted a runway marker during a go-around from a planned full-stop landing at Polson Airport, Polson, Montana. The private pilot, who was the sole occupant, was not injured, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 personal pleasure flight, which originated at the Polson Airport about 15 minuets earlier, was being operated in visual meteorological conditions. No flight plan had been filed. There was no report of an ELT transmission. According to the pilot, he was performing a series of touch-and-go landings in variable gusty wind conditions in order to "...maintain proficiency on a gusty day." After three successful touch-and-go landings, the pilot decided to make the next landing a full-stop termination of the flight. During the subject landing, the wind shifted from a quartering headwind to a quartering tailwind, and although the touchdown was uneventful, during the landing roll the aircraft suddenly started turning toward the side of the runway. Although the pilot applied control inputs in an attempt to keep the aircraft on the runway, he was unable to overcome the effects of the varying wind conditions, and the aircraft departed the side of the runway. He therefore added full power in order to regain control and execute a go-around. During that sequence of events the left wing contacted the ground and the left horizontal stabilizer impacted a runway marker. The pilot was then able to complete the go-around, whereupon he flew a normal traffic pattern and retuned for a subsequent full-stop landing. He discovered the damage to the airframe after taxiing to his hanger and shutting the aircraft down. According to the FAA inspector who responded to the accident, there was no evidence of any anomaly in the flight control or wheel braking systems.