Flooding risk as front hits Hawke's Bay

A severe weather warning is in force for the region today as heavy rain presents a risk of slips, flooding and rising rivers.

The MetService warning, issued yesterday, said an intense front would lie over the north of Hawke's Bay and the south of Gisborne during much of the day, before moving away to the north this evening.

The front is likely to bring heavy rain to these areas and could cause rapidly rising rivers and streams, slips and surface flooding.

In the 18 hours from 3am to 9pm, MetService expected up to 150mm of rain, with peak intensities of 20 to 30mm per hour from about 10am to 9pm.

Low temperatures are also expected today, with the freezing level about 1500m, lowering to 1400m in the afternoon and 1200m tonight.

MetService forecaster Mariken van Laanen said the rain would last for most of today and ease tonight.

There could also be strong southerly winds, especially about the coast, Ms van Laanen said.

WeatherWatch.co.nz forecaster Philip Duncan said the region would "forget about the early spring for 24 hours" during the deluge.

"That's a month's worth of rain falling in a day. It's a significant amount and we do get flooding problems with that amount of rain."

Rainfall would be heavier about the ranges and patchier in the south.

Ms van Laanen said the outlook for the rest of the week was "generally fine".

Tomorrow would be fine with a possibility of showers east of Wairoa.

Wednesday was also expected to be fine, although a brief southerly change could bring the occasional shower.

There was a predicted upward trend in temperatures this week, from today's daytime high of 13C to a pleasant 18C for Thursday.

Tonight's overnight low is a chilly 1C but lows are expected to reach 8C toward the end of the week.

Mr Duncan said spring had arrived in the region "without a doubt". His comments came after a northwesterly flow brought balmy weather to Hawke's Bay at the weekend.

"Trees are in blossom, lambs are being born, there's pollen in the air.

"Mother Nature has already declared spring is here."