A spate of illegally lit fires has prompted the Southern Highlands fire brigades and Wingecarribee Shire Council to work together in preparation for what could be the busiest fire season on record.

RFS Acting Superintendent Ashley Frank said council and the fire services were concerned about the number of illegally lit fires across the district.

"Residents in the area must understand that all brigades are on high alert and ready in preparation for what could very well be the worst fire season in history," Mr Frank said.

"People must also be aware they could face fines of up to $50,000 for lighting a fire without a permit, with the exemptions of barbecues.

"Firefighters need landowners in the district to be diligent with fire lighting and when residents are near the urban bushland interface, if they could please think twice before lighting a fire."

Mr Frank added that with the majority of the district now in drought, fire crews were finding it more difficult to control fires, especially with the erratic weather conditions of warm temperatures and high winds.

"The fuel conditions are worse now than they were during the December/January bushfires, so it doesn't have to be a hot day for fires to take off," he said.

"Although the NSW and RFS brigades are better prepared for this season then we ever have been we cannot do it alone, we need the support and awareness of the local residents in regards to being fire safe.

"The fire services and the council are working together so if the public blatantly does the wrong thing then those people will be fined."

To report a fire in the area people should ring 000.

Mr Frank said local media would be broadcasting all fire reports, such as total fire bans, on a regular basis throughout the season.