A heavy rain warning is in force for the Bay of Plenty, Gisborne and Hawke's Bay this morning.

Severe flooding has hit the Tolaga Bay and Tokomaru Bay areas of Tairāwhiti.

State Highway 35 from Gisborne around East Cape to Ōpōtiki, is closed because of flooding, slips and washouts.

According to RNZ, Tairāwhiti Civil Defence has ordered the evacuation of residents in the Mangatuna area north of Gisborne, because the Hikuwai River is at a very high level and more rain is expected.

Tolaga Bay Civil Defence has been set up and anyone in immediate danger of flooding should move to higher ground, civil defence says.

It says whānau have been notified and civil defence teams have been going door to door.

MetService is warning more than 220mm of rain could fall in Bay of Plenty and up to 150mm in the Gisborne area, through to at least the evening and possibly into tomorrow for Gisborne.

Tairāwhiti Civil Defence is asking people to check for updates for weather and road conditions.

It says a lot of rain is due over the next 24 hours, and conditions are not improving.

-RNZ.