An Auckland Westpac Rescue Helicopter spokesman said a man in his 40s was flown to Auckland City Hospital in a critical condition.
Police also received a report of a two-car crash at that intersection of the Old North and Old Railway Rds in Kumeu at 5.45pm.
"There were three patients, two with moderate injuries and one with minor injuries," the spokeswoman said.
Crew of the Auckland Westpac Rescue Helicopter were tasked to Warkworth to assist a patient involved in a motor vehicle accident. Photo / Auckland Rescue Helicopter Trust
The New Zealand Transport Agency says traffic has been normal for a Friday night at this time on the motorways, despite this weekend being the start of the school holidays.
"There are no significant incidents to report," the spokesman said.
The agency is advising drivers to adjust their driving to the weather conditions to keep themselves and others safe.
"In winter there are fewer daylight hours and you're more likely to be driving in less favourable weather with reduced visibility, morning fog or wet roads," says Waka Kotahi Auckland operations manager, Rua Pani.
"Simple guidelines for winter travelling include ensuring your vehicle is safe, always driving to the road and weather conditions, allowing more time for travel, slowing down, being prepared for unexpected hazards and allowing greater following distance between you and the vehicle ahead."
Rua Pani says it's also important to watch out for other road users.
"During the school holidays there will be more children on the streets, walking and cycling, or visitors to the area who are not familiar with the road."
