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Rain and low cloud have hit the North Island this morning, causing traffic hold-ups around the capital and bringing a warning for campers and trampers.
Heavy rain warnings remain for both islands, but the weather will ease in the South Island during the day. The upper North Island will escape the worst of the front moving through the country.
But it's hardly consolation for the organisers of the Heineken Open tennis championships, which started in Auckland yesterday.
Motorists have been urged to take care on State Highway 1 between Otaki and Levin in Horowhenua, after massive downpours left surface flooding.
Sergeant Noel Bigwood said the Tararua Ranges behind Otaki had so far today recorded 176.5mm - 14mm more than the previous daily record.
Mr Bigwood said the flooding across the highway had come from the Waitohu Stream that had burst its banks.
"It's causing a lot of disruption and we're advising people not to travel unless they really have to. And if they do, allow plenty of time."
Te Horo Beach Road was also flooded after the Mangaone Stream overflowed.
Mr Bigwood said the Mangaone Stream had gone from a flow of about three cubic metres a second to nearly 30.
There have been accidents on State Highway 2 near Petone and State Highway 58, Paremata Rd, causing delays.
Forecaster Melanie Graham said the rainy weather was caused by a very wet, northwest flow from the tropics. "There's going to be a lot of rain around, widespread rain if you like, maybe not necessarily heavy falls but gloomy, grey skies. Certainly not idyllic camping weather I'm afraid for this time of year."
The MetService said this morning that heavy bursts of rain in the lower South Island could cause problems. "People in these areas, particularly trampers and campers, should keep close eye on river and stream levels, as these could rise rapidly," it said.
Rain was expected to start early today in much of the upper North Island, with the exception of Gisborne/Hawkes Bay, which won't get the wet until later in the day.
It was likely to linger until tomorrow when it should ease into showers. Thursday was still likely to be showery, she said. "It's not until Friday that we're looking at things kind of settling down."
Ms Graham said the weekend was looking a bit more promising, although it was still a long way out for a reliable forecast. The long-term forecast is for an easterly flow, meaning the weather in places such as the Coromandel and the Bay of Plenty would be less favourable than those on the west coast.
Ru Collin, an apple grower in the Hawkes Bay, said the rain would be welcome for pasture growth. But fruit growers prefer it dry. Irrigation is his preferred method of getting water to his crops, but rainfall has the benefit of being of the right temperature.
This year, the apple trees have been carrying big crops, he said. "The demands for moisture and nutrients are quite high and this rain should help improve our crops as well."
But the summer had not been too hot, and until the landscape goes "grey or chalk", there was still enough moisture in the ground, he said.
