Parts of the central North Island are being warned to prepare for heavy rain as a series of fronts move in from the Tasman Sea.

These fronts are being preceded by a moist northerly flow.

This image taken from the MetService's rain radar shows rain moving towards the region this morning. Image: MetService.

While there are no rain warnings in place for the Bay of Plenty and the Coromandel, the MetService is predicting showers to turn into rain this afternoon. Northeasterly winds are also expected to strengthen this afternoon.

'Heavy rain is expected in the north and west of the South Island during Wednesday and early Thursday, and in the north and west of the North Island from late Wednesday through to Friday morning,” says a statement from the MetService.

'Northerly winds are also expected to become strong about central New Zealand during Wednesday and early Thursday.”

Heavy rain warnings are in force for Fiordland, Westland, Buller, Nelson, Marlborough, Mount Taranaki and the Central North Island High Country.

No warnings are in place to the Bay or Coromandel, but the MetService will be reviewing this at about 9am.

'This is a developing situation and people are advised to keep up to date with forecasts in case parts of this watch are upgraded to a warning, or if further areas are added.”