Bay of Plenty braces for heavy downpour

Heavy rain and possible thunderstorms are forecast for the Bay of Plenty, including Rotorua.

Western Bay of Plenty was soaked overnight: MetService said Tauranga had 59mm of rain in 12 hours, and Whitianga 53mm.

Heavy rain may cause streams and rivers to rise rapidly, MetService said.

"Surface flooding and slips are also possible and driving conditions may be hazardous."

The rain warning is valid until Tuesday morning. A further 100 to 150mm of rain could accumulate, with most of the rainfall expected in the eastern ranges.