Four people lost their lives on NSW roads during the June long weekend. Three of the four crashes that claimed a life were on country roads in the southern region.

Southern Region Tactician Inspector Scott Nelson said this is two more than the Queen's Birthday weekend last year.

"I am urging everyone who is travelling home this afternoon or even coming back early tomorrow to be patient and not take unnecessary risks.

"If you feel tired, pull over, take a break and if you can change drivers," Inspector Nelson said.

Operation Stay Alert commenced at midnight Friday and concludes at midnight on Monday, June 10. Double demerits are in force throughout the period.

Officers will be highly visible on the roads during the operation, targeting speeding, mobile phone use, seatbelt and motorcycle/helmet offences, alcohol, drug-affected drivers, and fatigue.

Traffic and Highway Patrol Commander, Assistant Commissioner Michael Corboy said, "we are expecting more cars on the road today as people return from their holiday.

"If you are caught in traffic, be patient.

"You should not let your current circumstances tempt you into taking risks that place you or your family in more danger of being involved in a crash.

"I would like to remind regional drivers that no matter how well you think you might know a stretch of road that crashes can occur at anytime and anywhere.

"You need to be prepared for the unexpected and drive to conditions."

For up to date traffic information visit Live Traffic.

Southern region key statistics (progressive total)

NSW key statistics (progressive total)