The road was closed yesterday afternoon due to a slip, as the region was drenched in around 100mm of rain.
Thames/Coromandel District Council said Neavesville Rd in Matatoki and Puriri Rd in Te Kouma were also closed due to slips.
Tourist Kelsey Jacobson has been stranded by the slips and now has until 5pm to get to Auckland Airport and catch her 8pm flight back to Canada.
Jacobson has been watching the NZTA website all night and is hoping the bus due to depart Coromandel Town at 10.30am will get her there in time.
"The airline said the latest I can cancel is 2pm and it will cost $1000."
Jacobson has been holidaying in New Zealand since the end of June and the Coromandel was her last stop.
She had planned to leave on Sunday afternoon, but after the ferry and then replacement bus were cancelled, she ended up staying another night in a motel in town.
"Everyone was really helpful. Someone even shared their pizza with me."
The bus will detour via SH25a, where a stop/go traffic control is in place after a slip closed the road yesterday.
About a dozen other people were also waiting desperately at the information centre for the bus to take them to Auckland after being forced to stay last night in the town. Many had been in the town for the Illume Festival.
Grandmother Sheridan Smart was also on a tight timeframe to get to Auckland to look after her two grandchildren, aged 7 and 13, so her daughter could fly to Europe to watch her husband play rugby.
"She's absolutely stressing out."
Smart, who lives in Matarangi, said they braved treacherous condition to get the replacement bus last night only to find the service had been cancelled.
At one point the water level was up to the car bonnet, she said.
She returned to Coromandel Town this morning hoping to catch the bus.
MetService meteorologist Arno Dyason said the Coromandel ranges received the majority of the rain, after parts of Auckland were inundated earlier in the day.
The Coromandel usually gets about 200mm of rain throughout the entire month of July.
The heaviest rain hit about mid afternoon, leading to flooding and slips, trapping residents and holidaymakers.
The storm first wreaked havoc in Auckland early morning.
Between 8am and 10am rain was recorded at times of 40mm/hour, Dyason said.
Last night the storm continued east and Whakatāne Airport recorded about 24mm an hour around midnight.
The ranges above Gisborne and Hawke's Bay also received a drenching, before the system moved offshore to the east of the country this morning.
Today a showery, westerly flow was moving across the North Island, bringing a moderate risk of thunderstorms to most of the west coast.
