Police in Waikato say there were 35 crashes in the region on Tesday, many involving drivers who left the road in wet weather.
They are disappointed by the number of motorists who failed to drive to the conditions.
Speeding on corners cited as the major cause of the crashes.
Senior Sergeant Jeff Penno says no-one was seriously injured.
He says drivers, particularly those going to Coromandel, need to accept that their trip is likely to take much longer than usual at the moment.
Motorists are advised to allow plenty of time to reach their destinations, with heavy traffic because of the holidays.