The biggest rain in months due to scatter across parts of Queensland and New South Wales later this week will be far from drought breaking, but it will improve air quality, help shrink bushfires and reduce fire danger for weeks to come. Dozens of fires are still burning, more than a week after some ignited, reducing air quality in some areas, making life difficult for many. Late this week, parts of southern Queensland, NSW and the ACT will see their best rain in six-to-nine months, making a significant impact on the fire areas and surrounds. Initially, air quality will improve, fires will be reduced in size, some extinguished altogether, and the added moisture will help reduce fire danger for the following few weeks. Other positive effects include greening of gardens and parks, adding moisture to the ground and a bit of extra water in dams. However, falls will generally be modest, only marginally reducing the massive rainfall deficits, barely making a dent in the drought. The most likely areas to see their biggest rain in about six months or more are the Monto, Miles, St George, Brisbane and Gold Coast areas of Queensland, the Casino, Armidale, Moree, Tamworth, Dubbo, Sydney, Goulburn and Batemans Bay areas of NSW and in the Canberra area. The rain-bearing weather system doesn't look like being particularly intense (a weak low pressure system and pool of cold air) but it should be slow-moving enough for wind to turn moist easterly in the few lead days. It is this moisture which is crucial for any worthwhile rain, potentially more than a month's worth in some places, most likely on the slopes, ranges and coast in northern NSW and nearby Queensland.