Rain and cold snap on way for region

The steeple of St Columba's Presbyterian Church in Havelock North, silhouetted against a cloudy sky. Photo / Duncan Brown

Hawke's Bay can expect a mixed bag of weather this week, with periods of rain and a cold change on the way, forecasters say.

It has been a warm farewell to winter, the temperatures across parts of Hawke's Bay more like mid-autumn numbers.

The twin cities enjoyed temperatures up to 17C during the first official day of winter yesterday.

A pleasant daytime high of 18C is also expected for both cities today, with strengthening northerlies, but MetService meteorologist Rob Kerr warned of occasional rain.

"We've got a broad, complex low sweeping across the country, with warnings in place for Bay of Plenty and Gisborne. Much of the rain is to the north of Hawke's Bay, but you will see some spilling across."

The trough coming in from the Tasman Sea would bring up to 100-120mm of rain to the far north of Gisborne in just 12 to 18 hours.

But there were no warnings in place for Hawke's Bay, although he said the showers meant there was a chance of rivers rising rapidly.

By contrast, tomorrow would be fine and "largely dry," while Thursday would herald a cold southerly change.

"Once the low tracks off it will be followed by cold southerlies and things will cool down significantly."

Daytime highs would drop to 15C by Friday, with southwesterlies dying, and an overnight low of 3C.

The cold snap would be due in part to still, dry conditions, which also saw chilly overnight lows of 1C in Napier last week.

"When the air is still and dry it gives the earth a chance to radiate heat - when it's windy it tends to mix the air up a bit," Mr Kerr said.

There would be a few showers, mostly confined to Cape Kidnappers, heading into the weekend.