Wind will change from the current northerlies to cooler southwesterlies from late Saturday.
Glassey said a front in the Tasman Sea would move to the South Island today, causing heavy rain along the West Coast there, before moving to the North Island on Saturday.
Day temperatures in Whangārei will hover around 29C today, dropping down to 27C tomorrow, and 24C on Sunday.
Kerikeri, Kaitaia, and Dargaville will experience similar temperatures over those days.
Whangārei is the driest of all major centres in Northland, with just 0.2mm of rain falling since January 19. But with 1mm needed to be recorded to classify as a rainy day, this means Whangārei has not had any rainy days for 36 consecutive days.
The longest dry period in Whangārei was 42 days, between December 5, 1990, and January 15, 1991.