Don't leave the house without a raincoat.
Heavy rain watches and warnings are in place for much of the North Island starting today; with conditions due to get worse from late tonight through to tomorrow and Friday.
MetService has issued a heavy rain watch for the north and eastern parts of Northland from about 6pm and says thunderstorms are also possible.
"Rainfall amounts may approach short duration warning criteria," MetService warned.
A spokesman said a low-pressure system over the Tasman Sea, and its associated fronts, are forecast to move southeastwards onto the North Island over the next few days - bringing with it bad weather.
"The weather system should bring rain to much of the North Island by the weekend, but especially northern and eastern regions."
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Auckland is also in for a lashing from about 8pm - as is north of Whangaparāoa and Great Barrier Island.
A gloomy day is on the cards for Auckland today; with cloudy conditions increasing and showers turning to rain from this afternoon.
Northeasterly winds are expected to become stronger by then too. A temperature high of 17C and overnight low of 12C is forecast in the City of Sails.
A heavy rain warning has been issued for the Coromandel Peninsula - where periods of heavy rain are expected to result in between 100mm to 150mm of rainfall from midnight tonight.
Locals are being warned of possible surface flooding and slips in the area as a result and motorists are being told that driving conditions may be hazardous.
"Heavy rain may cause streams and rivers to rise rapidly (also)," MetService said.
Those in the Bay of Plenty and west of Te Puke, including the Kaimai Range, can also expect heavy rain from the early hours of tomorrow morning.
A heavy rain watch is also in place for Gisborne, north of Tolaga Bay.
Again, people in those parts of the country are being encouraged to keep a close eye on weather updates as rainfall amounts may approach "warning criteria".
In the South Island, icy trees lining State Highway 1 in Taieri yesterday when temperatures in and around Otago dropped to -6.5C at 8am.
The trees were left looking like cotton-wool balls from a bird's eye view as a result.
MetService said warmer temperatures are expected in the area this morning - around 2C.
A high ridge of high pressure is also due over the South Island over the next few days - with the West Coast and Southland forecast to be mostly fine.
There will, however, be cloudy periods and light rain or drizzle in northern and eastern parts.