Some of the serious crashes have involved young people, he said.
In the past 24 hours, two people were killed in a crash in Gisborne, one in Auckland and another in Christchurch.
Greally said recent wild weather was another reason drivers need to be “patient, slow down, and never drive distracted or impaired”.
“Make sure you are always driving to the conditions, slow down on wet roads, and during severe weather events it is best to delay travel where possible.”
He warned police would continue to target dangerous driving, and motorists could expect to see officers “anywhere and anytime”.
“Road safety is everyone’s responsibility,” he said.
“Never get behind the wheel if you’re impaired by alcohol, drugs or fatigue and stay fully focused on the road without any distractions.”