A severe weather watch with heavy rain and thunderstorms forecast for Northland has police a warning motorists to be extra vigilant when driving in wet weather after 18 crashes in 34 hours.
Rain across the region may have delighted farmers but emergency service workers have been on the go over the past two days.
Between 8.30am Wednesday until 6.40pm yesterday there were 18 crashes, a majority of which could be attributed to the wet weather and slippery road conditions, reported to police across the region.
Police, fire and ambulance officers were kept busy yesterday morning with three separate crashes which saw cars flip and end up on their roof.
The first was near Oakleigh, south of Whangarei on State Highway 1, about 8.30am and involved a single vehicle. The female driver had to be helped out of the car and was taken to hospital with suspected spinal injuries.
The car blocked the northbound lane and a tailback began to form quickly in both directions before traffic control kicked in and the scene was cleared.
Police were called to Puna Rere Dr near Otangarei after a car ended up on its roof about 11.40am and, at almost the same time, officers near Pakaraka were called to a car on its roof as the occupants were climbing out.
And on Paradise Rd a Fonterra milk tanker stuck trouble when it appeared the trailer unit went into a roadside ditch and rolled, spilling hundreds of litres of milk about 9am yesterday.
Senior Constable Ewen Cumming said Fonterra staff arrived at the scene to remove the unit from the gravel road.
Northland Regional Council was advised of the spill and police investigations were continuing, Mr Cummings said.
Police did not have to go far for a crash in the Bay of Islands near Pakaraka.
A Ford Focus was heading north just before midday yesterday when the driver lost control on a sweeping bend about 1km south of the junction.
The car rolled on to its roof and came to rest on the other side of the road, blocking the southbound lane.
The accident happened directly in front of a police patrol car which was returning from an incident in Moerewa.
Constable Rhys Dempster, of Kerikeri police, said the Ford's sole occupant was uninjured and "very lucky" another vehicle wasn't travelling in the opposite direction at the time.
Speed was not a factor - he described the crash as a low-speed roll-over - but the weather may have contributed.
The slippery roads were the result of a long dry period followed by rain which drew out the oil and rubber from the road which in turn created an extremely slippery surface.
Whangarei police Sergeant Barbara Goodwin said given the wet roads the old message to "watch your speed and following distances and drive to the conditions" applied.
The crashes happened in Kerikeri, Waipapa, Raumanga, Kaimaumau, Kaikohe, Kaitaia, Kamo, Okaihau, Oakleigh, and Whangarei.
"While there plenty of crashes fortunately none of them were serious," Ms Goodwin said.
The crashes served as a graphic reminder to motorists how easily things could go wrong in wet conditions, she said.
MetService forecaster Cameron Coutts said the Kaitaia area had the most rain with 89.2mm between 9am Wednesday and 4pm yesterday.
This was followed by Kerikeri which received 53.2mm of rain during that period.
Whangarei had 25.6mm of rain and Dargaville saw 32mm.
"I'm sure it will be welcomed by farmers after the little bits and pieces in the last couple of weeks," he said.
A weather watch in Northland was in place and more rain was expected across the region today, with possible thunderstorms in the evening.
Mr Coutts said showers were expected tomorrow and could turn to heavy rain in the afternoon. The rain was expected to ease on Sunday, he said.