Rain is being forecast to hit New Zealand in the next couple of days.

A large high covering the country is expected to move slowly east on Monday and Tuesday as a front approaches from the Tasman Sea, according to the MetService.

'This front is expected to move northeast over the lower South Island on Wednesday, preceded by a strong, moist, northerly flow, bringing rain to western areas and warm temperatures to the east,” says a MetService spokesperson.

'The front becomes slow moving over the South Island on Thursday and gradually weakens.”

There is a moderate confidence of rainfall reaching warning amounts about Fiordland, excluding the Lakes, during Tuesday and Wednesday, with a high confidence about Westland south of Greymouth from late Tuesday through to Thursday, including the Otago and Canterbury headwaters.

Further north, there is a low confidence of heavy rain about remaining parts of Westland and Buller on Wednesday and Thursday.

In addition, there is a moderate confidence of severe gale north to northwesterlies about exposed parts of Fiordland, Southland, Otago and inland Canterbury, including Stewart Island, during Tuesday and Wednesday, with a low confidence about remaining parts of Canterbury.