Western Bay of Plenty and Coromandel are expected to suffer a heavy blow of rain this weekend.

MetService says the two regions are just some of many areas which will be affected by the weather system.

"A front is moving southwards over the upper North Island today, preceded by heavy rain and easterly gales.

"The heaviest falls are expected about Northland, Auckland, Coromandel Peninsula, Western Bayof Plenty and Canterbury south of the Rakaia.

The Warning now includes heavy rain for northwest Nelson, Bay of Plenty
east of Te Kaha and Gisborne north of Tokomaru Bay.

"Furthermore, east to northeast gales could become severe in Auckland, with possibled amaging gusts especially this afternoon and evening."

A complex low is also expected for tomorrow.

'This should lie northwest of the North Island on Sunday, bringing rain to northern parts of the North Island, and strong easterlies to much of northern and central New Zealand.

'There is high confidence that rainfall accumulations will meet warning criteria on Sunday over the Western Bay of Plenty and Coromandel, and a Heavy Rain Warning is in force for these areas.

'The low should slowly weaken on Monday, while an associated rainband moves southwards.

'On Tuesday, a ridge of high pressure should move from the South Island onto central New Zealand, then on Wednesday a strong southerly is forecast to sweep up the east coast."