The NSW total fire ban came into effect at midnight on Tuesday and is in place until midnight on Saturday.

The community should be extremely careful over the coming days and farmers are urged to refer to their harvest guides and check haystacks for signs of spontaneous combustion, Riverina RFS district officer Bradley Stewart said.

"The risk to our community is something that's very real and very present," he said.

"Currently the conditions we have are an average fuel load across the entire area of about 1.5 tonne/hectare in the grassland area. The curing of grass - the dryness - is about 98 per cent, so it's fully available for combustion should fire (break out)."

The sweltering Riverina forecast has temperatures as high as 42 degrees on Wednesday, up to 44 degrees on Thursday, and even further to 45 degrees on Friday and Saturday.

What is on the region's side is the forecast winds, which except for Thursday, are relatively mild. But there is still no rain in sight.

"We really don't want to see any ignition occur here because it will be challenging (to tackle), we will have to throw resources at it very quickly," Mr Stewart said.

"People have to be mindful of what they're doing, what their actions are.

"For the next four days using angle grinders, welders, gas cutters in the open is prohibited. Farming operations such as slashing and cropping activities obviously carry an elevated level of risk and while those activities aren't prohibited, we do encourage farmers to ensure they have adequate fire protection in place."

Campers on private property need to pay attention to their safety and local conditions, and be aware of heavy fines that apply if fires are lit on total fire ban days.

"It's important that anyone who is going camping ensures that they don't light a campfire during a total fire ban, you can't use a gas barbeuce during a total fire ban," Mr Stewart said.

"You need to have the landowner's consent to have a campfire should there be no total fire ban, and not all reserves that are managed by councils or Crown land along the Murrumbidgee River allow for campfires to occur.

"Ignorance is not an excuse."

In other news

Campers bound for the region's dams and river reserves should also remain vigilant, with Forestry advising people to prepare for longer stays at Blowering Dam.

Access to the dam could be cut if fire breaks out in the Bago State Forest, which will be closed if the region faces severe to catastrophic weather conditions.

"Campers need to note that regardless of what the fire danger level is, there is a solid fuel fire ban in place," general manager of Forestry Corporation's Snowy Region, Dean Anderson said.

"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."