Hi Bob,
      I think the occasion you refer to could have been on one of the tarns up at Mt Field National Park - I was up there once for the Tas University Bushwalking Club's annual bash, and we had a fine snowball fight on one of them - the ice was at least 12cm thick! As you say, this could be a great song to sing in defiance of all those wimpy mainlanders who carry on if it drops below 10 degrees - 'I am a man of Tassie weather...'