"It will be a mostly cloudy day with showers here and there, but not as heavy as they have been today, particularly for the broader area of pretty much the northern half of the North Island, which has seen quite a lot of activity today,'' Mr Gall said.
"It will be less so tomorrow, and on Friday we're expecting it to probably become fine with westerly winds in Auckland.''
Today's thunderstorms would bring some relief from the high humidity which had kept temperatures feeling warm in the upper North Island, with the air feeling fresher tomorrow, he said.
"The air should be drying and cooling a bit, probably during tomorrow morning you'll notice quite a difference.''
Tomorrow the west and northern North Island will see some showers, with possibly a few heavy ones in the afternoon, while the east coast of the North Island down to Canterbury will likely see periods of rain, which at times may be quite heavy, he said.
There is a heavy rain warning in place for the Coromandel Peninsula and Bay of Plenty, Gisborne, and Hawke's Bay areas for this evening and into Thursday afternoon.
Wairarapa, including the Tararua and Rimutaka Ranges, and north-eastern parts of Marlborough, including the Kaikoura Coast and Richmond Range, also have a heavy rain warning in place until Thursday evening, with up to 100mm of rain expected to fall.
"The west coast of the South Island and the far south will generally be pretty good, and the remainder of the east of the South Island, from Dunedin up to about Christchurch, will be mostly cloudy sort of weather with some morning drizzle.''
*****
Main centres:
Auckland - Occasional showers and northwesterlies, a high of 22C.
Wellington - Rain, with a strong southerly which could see gusts of up to 90km/h in the afternoon. Temperatures will be low, with a high of 15C.
Christchurch - Cloudy with morning drizzle and easterly winds. A high of 16C.
Dunedin - Cloudy periods and north-easterly winds. A high of 18C.
