During a cross country flight, the weather began to deteriorate. The pilot elected to turn back; however, the weather continued to deteriorate and the pilot elected to perform a forced landing to a dirt road. The pilot stated that it was raining and there was lightening all around. During the forced landing the airplane started to sink and hit the ground hard. The pilot stated that the left main landing gear was bent aft and the left wingtip hit the ground. There were no mechanical anomalies with the airplane that would have precluded normal operation.