The Thames Coast Road near the Coromandel township of Ruamahunga has been closed due to a tree blocking both lanes.
A photo shows a tall pine that has fallen down a bank and is lying across the road. A video shows a large queue of vehicles halted by the incident.
Newshub reporter Karen Rutherford was at the scene and said it was one of a number of slips across the region over the past few days.
"There's been 400mm of rain in the last 72 hours and Civil Defence says there's a lot of water up there in the Pinnacles and it does take some time to make its way down," she said.
"People can expect there will be further slips and they're urging caution over the coming days, even though the weather is due to improve here overnight and into the weekend."
A police spokesperson said diversions are in place and motorists are advised to avoid the area and expect delays.
"Contractors and police are working hard to reopen the road," they said in a statement.
"At this stage we expect the road to be closed until 8:30pm. Thank you for your patience."
