The 15-year-old's high school - Hastings Secondary College - was the last in the NSW mid-north coast town to close on Monday, reduced to minimal supervision as the state's bushfire crisis continued.

With the mercury expected to hit 32 degrees in Port Macquarie on Tuesday, along with an extreme fire danger rating, Patrick told AAP his family had prepared for the worst.

"Smoke has pretty much blanketed the town," he said.

"It's very thick and you can easily taste it ... you probably can't see very well 100 metres in front of you.

"It's definitely very scary. And to see it affecting my town and me personally, it feels very threatening."

NSW Premier Gladys Berejiklian declared an official state of emergency on Monday in anticipation of "catastrophic" fire danger conditions expected in the Greater Sydney, Greater Hunter and Illawarra-Shoalhaven.

The declaration transfers a range of powers from the state government to the NSW Rural Fire Service commissioner, including evacuating people from dangerous areas and taking possession of property in the course of an emergency response.

Ms Berejiklian has refused to engage in discussions connecting the bushfires to anthropogenic climate change.

But Patrick, who was a Port Macquarie Schools Strike 4 Climate organiser in September, said now is the right time to address the issue.

"This is really scary - it feels almost like our first look at what might lie ahead," the grade nine student said.

"If now is not the time to talk about climate change, then when is?

"It's not the 'greenies' who are politicising (the bushfires), it's actually the firefighters and emergency services."

Australian Associated Press