Hotter, dryer and more fires: climate change report

That is the prediction for the state's west according to new data developed following a research partnership between the NSW and ACT governments and the University of NSW Climate Change Research Centre.

The extra heat would mean by 2070, areas around Bourke were likely to see another 40 hot days each year, on top of the 70 they already had, so temperatures above 35 degrees were in order for nearly a third of the year.

Dubbo would most likely see a 50 per cent increase in the number of hot days by 2030, and hot days would double by 2070.

While changes in annual rainfall would be small, seasonal rainfall was likely to change with much of western NSW seeing more rain in autumn and less in spring and winter, according to the NSW Office of Environment and Heritage.

It said overall, western NSW was expected to experience an increase in average, maximum and minimum temperatures of about 0.7 degrees by 2030 and more than 2.1 degrees in 2070. The biggest changes would be in spring and summer, with maximums jumping by 3.1 degrees by 2070.

The north west plains area from Moree west to Bourke would see an extra 40 hot days a year by 2070.

Along the central tablelands and slopes there would be fewer cold nights, with 20 to 40 fewer nights below two degrees each year by 2070.

The greatest increase in fire weather would also occur in the far west. Increases in severe weather days during spring might also increase bushfire risk and reduce opportunities for hazard reduction burning.

The new data was aimed at providing climate projections to 2070 to guide local decisions that would help minimise potential risks of climate change, Environment Minister Rob Stokes said.

The projections covered changes in temperature, rainfall, wind, humidity, evaporation and 100 other climate variables to 2070, and would be accurate to the nearest 10km.

"We've spoken to farmers and councils across the state who have said the portal will provide valuable information for long-term planning of their business and development," Mr Stokes said.

"This portal will be part of a continuing release of information about how climate will impact soils, biodiversity, bushfires, coastal impacts and flooding."

The information was freely available to members of the public at www.climatechange.environment.nsw.gov.au .