"Anywhere north of Kapiti, it's expected that for this evening through to tomorrow morning we've got gusts [forecast] up to 110km/h."
The thunderstorms that hit the north of the North Island this morning had now moved out to the east of the country, but there was a possibility they could be replaced with more moving up the country this evening, she said.
"We can see that there's quite a few strikes out to the west [of the North Island] at the moment, but it's just a possibility of thunderstorms at the moment -- they certainly won't be anywhere near as bad as they were this morning."
Tomorrow, most of the wild weather was expected to clear, with the forecast strong winds due to diminish in the morning, Ms Ranger said.
However, a strong westerly flow would remain, bringing showers to western areas of the country, she said. Eastern areas of the country should remain fine.
"Basically we've had some very, very cold air aloft, so that means we've got quite unstable conditions -- that's kind of what's been triggering all these heavy showers and thunderstorms."
Friday would be mainly fine for most of the country aside from scattered showers in central areas, Ms Ranger said.
Rain and showers were forecast for the south and western areas of the South Island.