Heavy rain is forecast for the Bay of Plenty ranges east of Ōpōtiki on Tuesday, MetService have said.
Streams and rivers in the area may rise rapidly and surface flooding and slips are also possible.
MetService have warned driving conditions could be hazardous.
Around 60 to 90mm of rain is expected to accumulate with peak rates of 10 to 15 mm/h.
"An associated front is expected to become slow-moving over, or just to the north of, Northland on Wednesday and then begin moving southwards on Thursday. This is likely to bring an extended period of moderate or heavy rain to Northland," MetService said.