A burst of heavy rain and gales are expected to lash the North Island and parts of the South Island tonight and tomorrow.
MetService has issued a severe weather warning for heavy rain for Fiordland, Bay of Plenty, Waikato, Gisborne, Marlborough, Canterbury and Nelson.
Waikato Regional Council says between 80 and 120 millimetres of rain could fall on the Kaimai Ranges, placing further pressure on already swollen rivers.
The Council said rain could send the Piako and Waitoa rivers back up to levels seen earlier last week, while the Waihou could also come under pressure.
Emergency management officer Greg Ryan said: "Farmers and the general public need to be aware of the potential for rising river levels, slips and difficult road conditions."
MetService said heavy rain has been affecting southern Fiordland, but this should ease during Monday morning.
In the Coromandel, eastern ranges of Waikato, Bay of Plenty and northern Gisborne, heavy rain is expected to develop tonight and continue until Monday afternoon, MetService said.
The forecaster said that in Nelson and Marlborough the heavy
rain should set in early Monday morning and continue until about
midnight, with up to 120mm of rainfall predicted.
In eastern areas of Canterbury and Otago from the Rangitata River to Clutha district rain should become heavy around midday Monday.
South of Palmerston, the rain is expected to ease by midnight Monday, but further north it is likely to remain heavy until Tuesday evening.
Up to 150mm of rain could fall about the hill-country of South
Canterbury and North Otago, while further south 70mm is
MetService said that rain is expected to become heavy in eastern Otago tomorrow as the southeasterlies spread north.
Elsewhere heavy falls are likely for Northland, Auckland, Taranaki and Wanganui.
MetService is warning people in these regions to be aware of
river levels and watch for surface flooding and slips.
MetService forecasts show northeast gales and heavy rain are expected to spread across the North Island, and the upper South Island this evening and tomorrow morning.
Severe gusts are expected in exposed parts of Fiordland today. MetService warned that winds could reach 130km/h - strong enough to damage trees and powerlines and make driving hazardous.
The winds are expected to begin to ease Tuesday morning.
The forecaster said a deep, slow-moving low to the west of the
North Island is directing a strengthening east to northeast flow
over the country.
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