The pilot was expecting to make an early morning DEPARTURE, but was confronted with adverse weather conditions and low cloud. He was advised by another pilot that these conditions were expected to improve later that morning, but he decided to depart immediately and assess the weather as the flight proceeded. After flying in a westerly direction for several minutes it became obvious to the pilot that visual flight could not be maintained, so he elected to return for a landing. Re-entering the circuit area the low cloud and poor visibility required the flight to continue close to the ground, and the pilot misjudged the turn onto final. He abandoned the landing and joined a low left hand circuit for the reciprocal runway. While turning onto a close final leg, the left hand wing contacted a six metre high telephone wire located across the approach path approximately 300 metres from the runway threshold, causing the aircraft to lurch violently to the left and impact the ground heavily