MetService meteorologist Sarah Haddon said rain was heaviest in the Raukumara Ranges in the west of Gisborne.
"We're seeing 130mm of rain, which is quite a lot."
In lower, more populated parts of the city rainfall was between 30 and 40mm and it was the same story in the Bay of Plenty as well.
The regions could expect continuous rain today followed by showers tomorrow.
"There won't be overly strong winds in those areas, there's just going to be continuous periods of rain throughout the day."
In Auckland, a "large blob of rain" was about to move over the city shortly before 7am, Haddon said.
"We'll definitely get a big burst over the next few hours."
A complex low that arrived from the north Tasman sea was making its way down the North Island today and tomorrow, bringing "quite a few troughs and fronts".
Persistent rain would accompany the slow-moving weather system and a weather watch was in place for Northland, Auckland, Great Barrier Island and the Coromandel peninsula.
The top of the South Island was also forecast to get rain, and Christchurch could expect a wet couple of days as well.
Today's forecast
WHANGAREI: Showers, chance heavy/thundery early morning. Northerlies, turning strong southwesterly evening. H 19C L 12C
AUCKLAND: Rain with some heavy and possibly thundery falls, turning to showers, some heavy, this afternoon. Northeast, dying out evening. H 18C L 12C
HAMILTON: Showers, some heavy. Northeasterlies, dying out in the evening. H 18C L 11C
TAURANGA: Rain at times, some heavy and possibly thundery falls. Northeasterlies dying out afternoon. H 18C L 12C
WELLINGTON: Periods of rain. Southerlies. H 13C L 9C
NELSON: Periods of rain. Southeasterlies, dying out. H 15C L 8C
CHRISTCHURCH: Drizzle, turning to rain morning, easing evening. Southwesterlies. H 8C L 5C
QUEENSTOWN: Fine, with variable high cloud. Southwesterlies developing. H 9C L 0C
INVERCARGILL: Fine, with variable high cloud. Easterlies. H 8C L -1C
