Mr O'Farrell has visited fire-affected areas in southern New South Wales this morning.
He greeted firefighters at Bookham, west of Yass, where a fire has burnt out more than 16,000 hectares and killed thousands of stud sheep.
The Rural Fire Service (RFS) says the blaze is still burning aggressively in places.
Mr O'Farrell says there is a long way to go before it is full contained.
"This fire is threatening homes around Yass and there are some very nervous people in and around this district," he said.
On the state's south coast, drivers have been stranded overnight after a fire near Sussex Inlet crossed the Princes Highway.
The road opened briefly this morning,
Also in the state's south near Cooma, a bushfire is burning out of control in the Kybeyan Valley.
About 8,500 hectares have been burned and crews are using aircraft to protect properties.
Firefighters have contained a blaze in Mates Gully, Tarcutta, near Wagga Wagga, to about 1600 hectares.
At Lithgow, in the state's central west, there is a 'watch and act' alert for a fire burning near the Bells Line of Road.
Meanwhile, Rural Fire Service has downgraded the threat of a fire near Mudgee in the state's central west.
The fire at Hargraves is now being controlled and no longer threatening homes.
The weather conditions that fuelled fires in the south on Tuesday have moved north, leading to a severe fire danger in the Hunter, up to the Queensland border and west to Moree.
The blaze at Muswellbrook near the Bayswater Power Station, in the Upper Hunter, is now under control and the New England Highway has re-opened to traffic.
A state-wide total fire ban remains in place with 31 bushfires still not contained.
Barry O'Farrell says the fact there have been no fatalities highlights how well the emergency services had planned for the catastrophic conditions.
The Department of Primary Industries says up to 10,000 sheep have been lost across the state, as well as cattle in the Riverina.
One home has been confirmed destroyed near Cooma.
Mr O'Farrell says he is in discussion with the Federal Government about disaster assistance.
For the latest information and alert levels for the fires go to the