Thunder and heavy showers could swirl over Auckland this afternoon, but the chance of a thunderstorm similar to yesterday's is low.
Yesterday almost 12,000 lightning strikes were recorded over the North Island.
And WeatherWatch forecaster Philip Duncan said there could be more heavy showers and thunder this afternoon, but it would be significantly less than yesterday.
The humidity left behind from the remnants of a weak low over the upper North Island has caused the afternoon thunderstorms.
The fog in Auckland this morning was evidence there was still high humidity, Mr Duncan said.