Mr Noll said there were three reasons behind Monday's record temperature.
"Look to Australia. A very impressive heatwave occurred over the weekend and into Monday as many locations set all-time record warm temperatures there."
Queensland and New South Wales are battling temperatures in the early to mid 40C, with people and animals treated for heat-related illnesses.
Queensland recorded 47.2C - the state's hottest ever February.
Mr Noll said some of the heat swept across the Tasman Sea on Monday, and headed for Northland.
"As the air passed over the higher terrain in western Northland (Tutamoe Ranges), it is forced to descend as it moves toward Whangarei.
"As the air descended the ranges, it warmed and reobtained some of the hot qualities it had when it was over Australia. This is known as a downsloping wind or a foehn wind."
Mr Noll said dry conditions in Northland meant ground heat radiated all over the region and created hot sticky conditions.
No record temperatures were expected for Whangarei later this week with rain up to 75mm forecast for some parts of Northland from today, continuing through to Friday.