On June 19, 2003, about 1100 Pacific daylight time, a Beech S35, N5828S, impacted an object while in cruise flight near Weed, California, and then landed uneventfully at Colusa County Airport (O08), Colusa, California. The pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The private pilot, the sole occupant, was not injured; the airplane sustained substantial damage. The personal cross-country flight departed Medford, Oregon, about 0945, en route to Fullerton, California. Day visual meteorological conditions prevailed, and no flight plan had been filed. In a telephone conversation with the National Transportation Safety Board investigator-in-charge (IIC), the pilot reported that during cruise flight he was distracted and looked down. When he looked up, he was in the clouds. He heard a loud "thump or bang" and immediately entered a climb. The pilot then made a planned fuel stop at Colusa, and discovered that the right wing leading edge was crushed, the bottom of the right wing was punctured, and the leading edge of the right ruddervator was slightly crushed. A Federal Aviation Administration (FAA) inspector examined the airplane. A crush located along the leading edge of the left wing extended from the fuselage outboard approximately 1 foot. The crush ended along a rivet line. A dent, similar to a concave circle with a 3-inch diameter, was present on the right-hand side of the nose skin. The right ruddervator displayed a crush mark in the center of the leading edge, approximately 6 inches in length. A reddish brown coloration was present at the crush points. Portions of organic material, similar to trees or brush, were lodged within the crush folds in the right wing. Siskiyou County airport is about 15 miles north of the pilot's reported position at the time of the collision event. The METAR observations for 2 hours before and after the reported time of the event were reporting clear skies and unrestricted visibilities.