The Dunns Road fire was listed as under control and had burned through more than 4600 hectares on Monday morning and a fire weather warning was issued for the region soon after 2am.

The Southern Slopes, Eastern Riverina and Southern Riverina fire areas are subject to the warning, which declares hot, dry and windy conditions will bring elevated fire danger.

The NSW Rural Fire Service (RFS) advises residents and visitors to those areas to action their bushfire survival plans now, monitor the fire and weather situation and call Triple 0 in an emergency.

Ember attacks from the bushfire east of Tarcutta could threaten properties around Adelong on Monday as high temperatures and northerly winds create 'severe' fire conditions, Peter Jones from the Riverina Highlands RFS told The Daily Advertiser on Sunday.

"The weather is going to put pressure on the south-eastern corner of the fire where there is a lot of activity going on and where we have had the Large Air Tanker working [on Sunday] to try and halt its progress," he said.

State forests around the Snowy Valleys, including Tumut and Tumbarumba, have remained open during the summer until now. They close when the fire danger is predicted to be severe and catastrophic.

The Southern Riverina and Southern Slopes fire areas are both under a severe fire danger rating for Monday, when temperatures are expected to soar past 40 degrees, and all forests around the region including Bago State Forest have been closed until further notice.

"We are asking anyone using state forests in this area to leave," general manager of Forestry Corporation's Snowy Region, Dean Anderson, said earlier in the month.

"The forest environment can be unpredictable and even if there does not seem to be fire close by at present, the weather over the coming days means that situation could change quickly.

"Now is the time to move on and make other arrangements."

Anyone planning to visit the area is asked to delay their trip.

Forestry Corporation warned prior to Christmas that campers on the Blowering Dam could be cut off if fire broke out in the Bago State Forest, where it would be safer to remain on the dam foreshore rather than travel back through the forest.

"Campers need to note that regardless of what the fire danger level is, there is a solid fuel fire ban in place," Mr Anderson said earlier in the month.

"That means no campfires, no charcoal burners and absolutely no fireworks.

"Police, RFS and the Forestry Corporation will be patrolling forest areas and around Blowering Dam; if you are provided with a direction to leave, we ask that you do so promptly and in an orderly fashion."