Flooding causes road closures in Katikati and a slip in the Karangahake Gorge. Photo / File
Flooding on State Highway 2 between Highfields Drive and Beach Rd, Katikati has closed the roads until further notice.
A traffic alert on the NZ Transport Agency's website said motorist should expect delays or avoid the area.
Due to a slip on State Highway 2 in the Karangahake Gorge, the road is also reduced to one lane until further notice.
Motorists were urged to take extreme care and follow the instructions of the contractors working at the scene.
Heavy rain is falling across the Western Bay and Bay of Plenty as a rain band moves south down over the country.
A severe weather warning is in place for Auckland, Coromandel Peninsula, Bay of Plenty, about the west of Te Puke, and the Kaimai Range, MetService says.
A MetService forecaster said people can expect more heavy rain as the evening progresses.
"This amount of rainfall could cause slips and surface flooding, as well as making driving hazardous, so people need to be aware of the risk and drive to the conditions."
More than 4000 properties in the Matua area were without power for about two hours this afternoon, while the power is still out at 37 properties in Whakamarama.
Powerco estimated it would be back on about 8pm.
It affects the area from the city centre to Greerton.