Rain will continue to smash down on the Bay of Plenty and Coromandel today.
The base track on Mauao has been closed for public safety due to storm damage, including slips and debris.
Tauranga City Council would reopen the track once it was safe.
A section of Grenada St between Sunrise Ave and Sandhurst Dr was closed off.
A tree was down along Takitimu Dr between 11th and 15th Ave overbridges.
There were also reports of houses being evacuated in parts of Papamoa and fire crews and councils were working to protect them.
The weather had caused a slip on Welcome Bay Rd, between Rocky Cutting Rd and Te Puke highway, which was blocking part of the road.
A small embankment slip along Oropi Rd near the State Highway blocked the footpath but not the road. It was coned off and will be cleared later today.
There were reports of a slip on the Kaimai Range.
There had been 22 calls between 3pm Tuesday till 6am this morning to Tauranga City Council related to water on the roads at Papamoa (Taylor Rd and Papamoa Beach Rd) and Tauriko (Gargan Rd).
MetService meteorologist Stephen Glassey said in the last 24 hours 118mm of rain had fallen at Tauranga Airport.
At least another 100mm could fall today, he said. There was a risk of localised downpours of 25mm to 45mm an hour.
"There is a significant potential for rain and heavy downpours in Tauranga today," he said.
The weather would continue to at least 8pm today.
A severe thunderstorm watch was in place for the Bay of Plenty with wind gust reaching 110km h this afternoon as well.
Mr Glassey said the weather was not usual for this time of year.
Rainfall of that intensity could cause flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.
Driving conditions would also be hazardous with surface flooding and poor visibility in heavy rain.
These severe thunderstorms had the potential to bring strong wind gusts exceeding 110km an hour.
Wind gusts could cause some structural damage, including trees and power lines, and may make driving hazardous.
In 28 years of living in Given Ave, Whangamata, Nita Petersen had never seen her property flooded as much as it was this morning.
"I couldn't believe my eyes when I looked out this morning and saw the flooding. I managed to lift everything important off the floor in my studio but when the water started lapping at the entrance to the house I rang 111," she said.
She suspects the ground in her neighbourhood had not recovered entirely from the floods of March 8 to 12 when a year's normal rainfall fell on Whangamata in four days.
Western Bay of Plenty District could have fewer councillors to vote for next election.