AU - A report by the Federal Government's commodity forecaster confirms expectations that the 2010 wine grape vintage will fall, but warns of a return to a near-record harvest in two years.The Australian Bureau of Agricultural and Resource Economics predicts national production will be down by almost 5 per cent this season to just above 1.6 million tonnes.ABARE attributes most of the fall to a heatwave that damaged inland crops."Wine grape production is expected to be lower because of lower yields in the warm climate zones which can be attributed to the prolonged heat wave in November 2009," the report says.