Keep a brolly handy tomorrow as Auckland Anniversary weekend continues to give the Bay of Plenty a mixture of sun and rain.

The MetService is predicting cloud with the odd shower tomorrow. But it's not all doom and gloom with the day expected to see the fine spells increase throughout the day, with sea breaezes and a high of 23C and an overnight high of 18C.

Summer continues with sunny skies and light winds forecast to start the week the MetService says. It will be staying fairly humid though, with temperatures in eastern areas likely to get into the thirties mid-week.

Warm, humid conditions have led to some spectacular thunderstorms in the north of the country this weekend. Localised rainfall of 50-70 mm per hour was generated by some of the thunderstorm cells over Northland on Saturday.

With high pressure building over New Zealand, the warm weather will continue into the start of next week.

'Sunny skies and light winds will be enjoyed by most for the start of the new school year, with just a few afternoon showers forming about the ranges,” says meteorologist Emma Blades.

'Wednesday is looking to be the hottest day of the week for many, with temperatures forecast to get into the thirties in eastern areas, the lower North Island, and central Otago,” Emma says.

On Thursday a front moves onto the far south, then slowly moves north, bringing drizzly conditions to the west of the South Island.

The rest of the country should continue to stay dry, but an area of low pressure looks like it may deepen to the northwest of New Zealand on Friday, possibly bringing some wetter weather up north by the end of the week.

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