"And that's bringing some quite heavy rain up through to Nelson, Buller, Marlborough, Canterbury High Country and Wellington."
Ms Blades said tomorrow would be wet for most places, as a deep low moved across the lower South Island, while an associated trough moved across the rest of New Zealand.
"The South Island is going to get rain in most places. It will be heavier in the west, as it usually is. It's a bit drier in the east but they will get some scattered falls there.
"For Taranaki and Wellington it looks like they are going to get the brunt of the weather on Saturday. There will be rain and showers for the rest of the country."
She said Sunday would be more settled for the North Island and the east of the South Island.
Today it would be mostly cloudy in Auckland with some patchy drizzle in the morning turning to afternoon rain.
"On Saturday we have some further showers developing, they might be heavy at first, but they will be clearing in the evening."
Ms Blades said Sunday was looking to be the best day of the weekend in Auckland. Monday would also be nice, with some light winds.
Cricket fans in Napier for Sunday's match between the Black Caps and Afghanistan could expect fine and dry weather, she said. Westerly winds would ease.
Tomorrow's weather
Whangarei H 28C, L 17C
Morning drizzle and brief afternoon rain, with northerlies changing to westerlies.
Auckland H 26C, L 17C
Morning drizzle and brief afternoon rain, with northerlies changing to westerlies.
Hamilton H 26C, L 14C
Drizzle and afternoon rain, possibly heavy, with northerlies changing to westerlies.
Tauranga H 25C, L 17C
Drizzle and afternoon rain, possibly heavy, with northerlies strengthening.
Wellington H 21C, L 14C
Rain, briefly heavy, clearing in the evening, with northerly gales gusting to 90km/h.
Forecast for Sunday's Cricket World Cup game:
Napier H 26C, L 14C
Fine and dry with westerly winds at the start of the game but easing towards lunch.
- Source: MetService