THE worst fire conditions ever seen in November are expected today as the mercury rises to about 40 degrees and beyond across NSW.
The Rural Fire Service, already stretched with 1000 firefighters battling more than 140 blazes across the state yesterday, is bracing for what Assistant Commissioner Rob Rogers described as the most dangerous combination of heat, wind and dryness.
''It makes fires very, very difficult to control, if we don't catch them very quickly we won't be able to put them out,'' Mr Rogers said. Crews were readying themselves for what they feared would be a nightmare 24 hours.
''Obviously they've been very busy but they'll drag themselves out for another day,'' he said yesterday. ''We've just got to get through tomorrow and then the weather calms down for a couple of weeks.''
The RFS has issued an extreme fire warning for the greater Sydney area, the highest so far this year.
The Bureau of Meteorology predicted highs of 41 degrees in Sydney and western NSW today.
Extreme warnings were issued for Richmond and the Hunter with temperatures predicted above 40 degrees and strong north-west winds expected to make fire-fighting conditions more difficult.
Premier Nathan Rees said the weather was unprecedented and warned people in fire-prone areas to remain vigilant. ''It has never been this hot, dry or windy in combination ever before,'' Mr Rees said.
NSW Ambulance is bracing for a spike in heat-related incidences after Friday's high temperatures resulted in a higher than average number of people dialling triple-0 with cases of heat exhaustion.
A man in his 60s was hospitalised after collapsing on a golf course because of the heat, while several distressed children had to be rescued from cars they had been left locked inside by their parents.
''We're asking people to be more vigilant about not leaving children in cars for even a few minutes,'' a paramedic spokeswoman said yesterday.
NSW Ambulance advised Sydneysiders to be aware of the dangers of heat exposure today and advised people to stay indoors, keep their fluids up and not to go out in the middle of the day.
The warning was emphasised for the elderly and very young, who are more vulnerable to heat illness.
''We're reminding mums that bubs need to be breastfed more often,'' the spokeswoman said.
The city sweated on Friday night, with the temperature still at 32 degrees at midnight. But a cool change a few hours later brought some relief across the state and offered respite for firefighters in the morning.
But even with temperatures lower than expected in many places on Saturday, heat records for November continued to tumble over the weekend.
The town of Hay is on its way to the hottest November in 128 years, tallying an average of 36 degrees so far this month.
Albury, on the Victorian border, has also suffered under a prolonged hot spell, recording temperatures above 33 degrees for 13 days in a row.