After a reasonably settled week so far, showers and heavy rain are forecast for the Bay of Plenty this weekend.

A low and associated fronts are expected to weaken and move north-east over the South Island on Thursday, before hitting the North Island on Friday.

Rain is expected to be heavy on Sunday. Photo: MetService.

Strong to gale north-westerlies precede the low and fronts, with rain expected about western and southern areas, says the MetService.

There is a moderate risk of heavy rain expected in the Bay of Plenty on Sunday.

'Cold rain is expected to spread north over eastern and southern parts of the South Island during Friday and Saturday, with snow expected to about 400 metres,” says the weather organisation.

'There is a moderate risk that snow accumulation could approach warning amounts above 400 metres about Canterbury and Marlborough from Friday to Saturday, with a small possibility that it could extend into Sunday.”

Meanwhile, a low is expected to approach the North Island from the north Tasman Sea during Saturday, with easterlies and rain spreading over the North Island during the weekend.

'At this stage, the position and depth of this low is fairly uncertain, however, currently the heaviest rain is expected about northern and eastern parts of the North Island.

'There is a moderate risk of heavy rain about Northland, Auckland, eastern Waikato, the Coromandel Peninsula, Bay of Plenty, Gisborne and Hawkes Bay from Saturday to Sunday, and a low risk about Wellington, Wairarapa and the Marlborough Sounds.”