The long, hot summer is continuing with a total fire ban declared for southern parts of the region and everywhere set to swelter.

Forbes will be the hottest location on Friday with mercury set to soar to 44 degrees, with Cootamundra and Wellington just behind at 43 degrees.

READ ALSO: Coronavirus is an international emergency, WHO says

A top of 42 is on the way for Cowra, Dubbo, Parkes and Young, with 40 on the way for Mudgee and Goulburn.

Bathurst and Oberon will see a top of 39 degrees, Orange will reach 37 and Lithgow will be the coolest spot in the region at 36 degrees.

If predicted maximums are reached on Friday, Oberon looks set to smash its hottest January day on record of 36.0 degrees.

While Cootamundra, Goulburn, Lithgow, Wellington and Young could come very close to breaking January heat records.

Police and emergency services are urging everyone in NSW to remember the four key messages to keep healthy in the heat:

While it is advised to avoid the sun during the hottest part of the day, large crowds are still expected at NSW beaches, rivers, lakes, and swimming pools.

READ ALSO: Fire expected to creep closer to nation's capital

State Emergency Operation Controller, NSW Police Force Deputy Commissioner Gary Worboys, urged those cooling off by the water to be vigilant, and stay safe.

Anyone swimming in unfamiliar waterways is urged to take extra care - every year thousands of people require rescuing from the surf and many needlessly drown," Deputy Commissioner Worboys said.

"Special care should be taken when swimming in rivers and dams where submerged objects may pose unexpected risks.

"I want to send a strong message to parents: if your children are out swimming, whether that is at the beach, a river, a dam or your backyard pool, and regardless of their age - they need to be supervised."

Why not subscribe, the first 30 days of full website access is free.