More flooding and slips are possible for the top of South Island, as another bout of heavy rain approaches

MetService has issued new Orange Rain Warnings tomorrow, covering much of Nelson, Tasman and Marlborough - with a moderate risk of it upgrading to a red warning.

Meteorologist Mmathapelo Makgabutlane is again flagging possible issues.

She says pre-existing conditions from heavy rain over recent weeks, make the area vulnerable.

She says with more falls, there could be more flooding and slips and impacts on driving.