Wellington has had a small taste of last winter's weather woes, with almost half its monthly rain for May falling in a little over two hours.
The downpour just before dawn on Wednesday blocked drains and caused extensive surface flooding.
Staff at one city supermarket started their day washing away the mud from the underground carpark.
Many homeowners woke to early morning leaks and some ceilings simply couldn't cope with the deluge. The fire service has had around 30 calls from people in Kilbirnie, Newtown, Kelburn and Karori concerned about water coming into their homes.
There was surface flooding in Wellington, Hutt Valley and Kapiti.
Allister Gorman from MetService says there were heavy falls between 5am and 6am, and in particular one short, sharp burst around 5:30am.
Police say bad driving conditions may have been a factor in a crash on Porirua's Whitford Brown Avenue just after 5am. A car collided with a lamppost and a man was taken to Wellington Hospital with serious injuries.
And five hours of continuous rain in Christchurch left some roads impassable. Nearly 13.5 millimetres fell between 6am and 11am on Wednesday. In suburban Wigram, police had to divert traffic.
