According to the pilot, several minutes after takeoff the weather began to deteriorate and the sky turned black with convective activity reported in the area. He decided to divert to a nearby airport which had a 4,000-foot long by 75-foot wide turf runway. As the pilot approached the runway he could not determine where the approach end was located. The airplane approached the runway high and fast. The pilot did not think he would be able to stop the airplane before reaching the end of the runway, so he aborted the landing. One witness reported that the airplane aborted the landing with less than 1/4 of the runway's total length remaining. During the attempted climb out, the pilot felt that the engine felt less powerful and but could not recall any specific abnormal indications. Without sufficient airspeed to climb above approaching trees, the pilot stalled the airplane into a pond, resulting in substantial damage to the left wing and empennage. Examination of the airplane by a Federal Aviation Administration Inspector following the accident revealed no evidence of any pre-impact mechanical malfunctions or failures. The weather conditions reported at an airport 5 nautical miles southwest, about the time of the accident included a temperature of 35 degrees Celsius and a left quartering tailwind at 6 knots.