An emergency warning issued for an out of control bushfire in northern NSW has warned residents the fire is "very dangerous and spreading quickly", telling some it is now too late to leave.
The fire is burning at Busbys Flat, Wyan, Myrtle Creek and Rappville - south of Casino - and has burned through more than 4200 hectares, the Rural Fire Service said on Tuesday.
"If you are in the area of Rappville, Wyan, The Island, Myrtle Creek, Wineshanty, or Mount Belmore State Forest it is now too late to leave," the RFS said in its official advice.
"Take shelter as the fire approaches and protect yourself from the heat of the fire. The fire is moving quickly in an easterly direction and has crossed the Summerland Way ... (it) is very dangerous and is spreading quickly."
The RFS says firefighters are battling strong winds and hot conditions as they fight the blaze.
Those winds are blowing embers ahead of the fire front, creating spot fires that are threatening properties before the main fire front arrives.
Earlier in the day RFS spokesman Greg Allan said conditions were not tipped to ease until later in the week.
"We're probably not going to see any reprieve until tomorrow," he told AAP.
"We've been seeing very strong westerly winds pushing that fire towards the east, still very high temperatures and very low humidity."
Emergency warnings have also been issued for two other bushfires burning in northern NSW.
The out-of-control blazes at Kildare Road at Tenterfield and Long Gully Road at Drake triggered emergency warnings on Tuesday afternoon.
Residents living in the Tenterfield area have been advised to seek shelter as the fire approaches.
RFS spokesman Greg Allan said the fire was burning five-to-10 kilometres west of Tenterfield which has a population of just over 4000.
"It's burning under very strong westerly winds, it's heading in an easterly direction towards Tenterfield," Mr Allan told reporters in a recorded message.
"The advice for those in the Kildare Road area and West Tenterfield is to shelter in place as the fire approaches."
The fire burning in the Drake area is currently over 66,000 hectares in size and has crossed over the Clarence River and the Clarence Way and is continuing to burn in an easterly direction.
"Residents in the areas of Ridge Road, North Ewingar Road, Grandview Road, Hunters Road, Valley View Road and Peckhams Road should take shelter as the fire approaches," the RFS said.
Amid sweltering heat - with temperatures tipped to reach 37C on Tuesday - total fire bans were enacted in the far north coast, north coast, New England and northern slopes areas, which are all experiencing severe fire danger.
People living in the worst-affected areas have been warned to ensure they have an escape plan.
The RFS tweeted: "Make sure you and your family know what you will do if fire threatens. Ask yourself - when will you go, what will you take and where will you go?"
Despite a cooler weather forecast from midweek - with temperatures expected to drop to the mid-20s - continued dry conditions meant fire dangers would not immediately fall away, meteorologist Jonathan How said.
"With no significant rainfall, fire dangers will remain high to very high until at least the end of the week," he said.
- Australian Associated Press
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