Bushfires have destroyed at least two New South Wales houses and injured two firefighters.
The NSW Rural Fire Service (RFS) says one house has been lost at Hawkesbury Road at Winmalee, in the Blue Mountains, and two firefighters battling the blaze there suffered minor burns.
A second house has been confirmed lost in Marsden Park in the Blacktown area, in Sydney's west.
Five firefighters have been treated for smoke inhalation.
Briefing parliament on Tuesday, NSW Premier Barry O'Farrell said 59 bush and grassfires were burning across the state with more than 500 firefighters and 200 appliances on the ground.
RFS deputy commissioner Rob Rogers said having so many fires in such a concentrated area around Sydney's greater west was a challenge.
"As far as the crow flies they're all not that far apart," he told Fairfax Radio.
"Unfortunately I think we'll probably see some more losses before the end of the day."
Winamalee High School was evacuated on Tuesday afternoon and was being used as an evacuation centre for residents of the small Blue Mountains town of Hawkesbury Heights.
In Castlereagh around 300 students from St Paul's Grammar School were evacuated to Penrith's Whitewater Park after an emergency warning was issued for a fire threatening properties on nearby Devlin Street.
Sisters Melinda and Samantha Millard, from Horsley Park, rushed to Castlereagh to help their horse trainer only to be told it was too dangerous.
Melinda said her friends were at the heart of the fire zone trying to save their horse training facility.
"It's scary, it's not even my place, but knowing it could go any minute now is making me really emotional" she said.
"We want to help people and the animals."
More than 2000 people were evacuated from a University of Western Sydney (UWS) campus following a power outage affecting the entire Richmond area.
The RFS has issued emergency warnings for fires around the greater Sydney region including Marsden Park and Windsor.
The warm 50kmh winds fanning the fire are likely to ease on Tuesday evening, a Bureau of Meteorology spokesman told AAP.
"(Tuesday) was certainly the hottest and windiest (day) of the week," she said.
It hit 32 degrees C in Sydney on today, but temperatures tomorrow are expected to be about 10 degrees cooler and winds will calm to about 30 kmh.
"It will be a significantly different day."
Police minister Mike Gallacher is being escorted by police under lights and sirens to a briefing with the RFS at Homebush.
- Sydney Morning Herald