Days of heavy rain expected

Manawatu is in for a wet and wild time as the remnants of Cyclone Debbie move towards New Zealand.

The first of the heavy rain was expected to start last night and could last through to Thursday.

Metservice forecaster Cameron Coutts said the rainfall would not be severe for Palmerston North, but the area was in for a significant downpour.

‘‘We are talking heavy falls until at least Wednesday.

‘‘There’s some potential for quite a bit in the Tararua Ranges.

‘‘But there could be 100-150mm on some of the low-lying parts of Manawatu.’’

In Whanganui, rain was expected to become heavy overnight on Tuesday, turning to showers during Wednesday. Up to 250mm could accumulate in the 33 hours to midday Wednesday.

In the Tararua Ranges, rain was expected to become heavy early Tuesday, turning to showers later on Wednesday. In the 30 hours to midday Wednesday, up to 250mm of rain could fall.

Further heavy rain was possible late Wednesday and early Thursday.

‘‘This is a significant amount of rain for these areas and people are advised to watch out for rapidly rising rivers and streams, and possible surface flooding and slips,’’ Coutts said.

After Thursday, a ridge was expected to arrive, which would clear the bad weather away.

Monday also saw rainfall in Palmerston North, but it was not related to Cyclone Debbie.

A collection of fronts was sitting around central New Zealand early on Monday, Metservice duty forecaster Matthew Ford said.

A southerly push had come up the east coast of the South Island and had extended over the lower part of the North Island. At the same time, there was a fairly moist northerly airstream over much of the North Island.

‘‘The two are colliding over central New Zealand,’’ Ford said. ‘‘Debbie hasn’t quite come down yet.’’

The warm moist air that had come down from the north and settled over much of the North Island had brought low cloud and drizzle.

A Horizons Regional Council spokesperson said hydrology and emergency management staff would be keeping an eye on river levels across the region.

The Horizons Emergency Coordination Centre had been activated at a low level in preparation for the forecasted wet weather.

Horizons controller Ged Shirley said staff would be monitoring river levels and keeping in contact with city and district councils should a response be necessary.

Wellington was forecast to have rain from Monday through to Wednesday, with southeasterlies rising to gale strength in exposed places on Tuesday, when a high of just 13 degrees Celsius was expected.

Metservice forecasted the centre of the country was likely to have the most days of rain during the week.

The wettest days were expected to be Tuesday and Wednesday.

Metservice meteorologist Stephen Glassey said it was important to note the deepening low left over from the remnants of Cyclone Debbie bore little resemblance to a tropical cyclone other than the fact it contained loads of tropical moisture, bringing with it the potential for heavy rain.

Palmerston North received rain and brisk easterlies with a 20C high on Monday.