Firefighters are still working to extinguish a 42-hectare fire at Mount Clear south of Canberra, following a day of sweltering temperatures and high winds.

The blaze near the border between the ACT and NSW has been burning since Wednesday.

Crews were expecting today's weather conditions to present new challenges.

The mercury reached 37 degrees Celsius about 4:00pm and north-westerly winds reached 30 to 40 kilometres per hour.

Very little new fire activity eventuated, but a nearby walking track and car park at Shannons Mountain were closed until further notice.

A total fire ban was in place across the ACT on Saturday and the fire danger level is severe.

The Emergency Services Agency (ESA) said the objective at Mount Clear today was to ensure that the fire, currently controlled in remote bushland, did not escape containment lines.

Reserves and roads closed: Tidbinbilla Nature Reserve

Tidbinbilla Nature Reserve Selected roads in Namadgi National Park including Apollo Road, Orroral Road, Old Mill Road, Warks Road, Mount Franklin Road and the Corin Dam Road

Selected roads in Namadgi National Park including Apollo Road, Orroral Road, Old Mill Road, Warks Road, Mount Franklin Road and the Corin Dam Road Googong Foreshores

Googong Foreshores Kowen Forest

Kowen Forest Lower Molonglo River corridor

Lower Molonglo River corridor Molonglo Gorge Nature Reserve

Molonglo Gorge Nature Reserve Mulligans Flat Woodlands Sanctuary

Mulligans Flat Woodlands Sanctuary Centenary Trail between Goorooyarroo Nature Reserve and Hall.

"Firefighters continue to use infrared cameras to identify hot spots and quickly extinguish any flare-ups. Crews worked in hot and dry conditions today but reported minimal fire activity," the agency said.



Six firefighters were expected to remain at the scene overnight to patrol the area.

There were concerns on Saturday that the fire could breach the border between the ACT and NSW, near the towns of Bredbo and Michelago.

The bushfire alert level for the Mount Clear fire remains set at advice, with people in the area advised to monitor the situation for changes.

Grassfire at Mount Taylor now under control

On Sunday afternoon a grassfire on Mount Taylor was quickly brought under control by firefighters.

At about 1:30pm residents of Pearce, Torrens and Kambah were urged to be on high alert and to monitor conditions.

The fire was initially listed as Watch and Act, but the alert level was wound back to Advice.

North of the ACT, a 12-hectare grassfire has been contained at Wallaroo in the Yass Valley in NSW.

The fire on Wallaroo Road was brought under control by firefighters from the NSW and ACT Rural Fire Service.

As a result of total fire ban declaration, a number of ACT nature reserves and remote roads are closed to the public.

The latest official information on fires in the ACT, as well as closed roads and reserves, can be found at the ESA website.