As scorching temperatures engulf NSW over the next few days, the danger of bushfires will increase across parts of the state.
The threat of fire will be at its greatest on Wednesday, when the mercury will hit 38C in Sydney and climb above 40C in other parts of the state.
"There will be a very high fire danger in the Hunter, Sydney, through the Riverina and Central Western Plains and through most of the state," Rural Fire Service Inspector Ben Shepherd said on Monday.
"West of the Great Divide there has been considerable grass growth, given that we came out of the third-wettest winter on record ... and that could act as tinder."
A heatwave is expected to intensify to severe or extreme levels past 45C this week around inland NSW.
Insp Shepherd said conditions are expected to ease on Thursday due to a southeasterly pushing up the coast, with temperatures dropping to 27C in Sydney and 30C out west.
"Fortunately at this stage the element that is in our favour is the wind speed; there isn't a strong wind for the majority of this week, that and the humidity are tempering the fire weather at this stage," he said.
Recent fires have burned through more than 5500 hectares, with an estimated $650,000 in crop losses, 300 sheep killed and the destruction of fencing.
RFS Commissioner Shane Fitzsimmons has urged farmers to protect their properties by putting in firebreaks around paddocks and other valuable assets and warned motorists not to drive through or stop in long grass.
"Even if it's just for a few minutes, as the heat from a car's exhaust can be enough to start a fire," Commissioner Fitzsimmons said.
"Grassfires can move more than three times as fast as a bush fire. Act now, be prepared and survive."
Thursday's reprieve won't last long, with temperatures due to climb again on Friday.
