Rainfall in Hawke's Bay last month may appear normal but a closer look reveals some parts of the region were left higher and dryer than others.

Hawke's Bay Regional Council climate scientist Dr Kathleen Kozyniak said the regional long term average rainfall was "bang on 100 per cent" in totality, but distributed rather unevenly.

"Essentially up in the northern areas it's been really quite wet, around one and a half times the normal rainfall up around Waikaremoana and Wairoa areas.

"As you progressively move south from there the rainfall drops to above normal, to normal and when you get to the Heretaunga Plains it's well down. The rainfall is only a little more than a third of the normal September rainfall and in Central Hawke's Bay they got around half their normal September rainfall."


Dr Kozyniak said the dramatic transition between north and south rainfalls were due to several lows tracking over the region.

"There's been a few lows tracking over northern areas which have caught the likes of Gisborne and northern Hawke's Bay but missed further south, so it's been a mixed bag."

After reviewing the coming season's forecasts, she said many models predicted north-easterly flows over the regions.

"That could bring us wetter weather if we're exposed to the direction of the flow but it depends how far that ridge to the east of us pushes over New Zealand, whether some of those lows fizzle out over the Tasman or if it's sufficient to bring wet weather to Hawke's Bay."

Dr Kozyniak said despite rainfall being significantly below average for the plains, soil moisture levels were average and future reports would likely indicate ground water levels were normal.

"Hopefully if we just get normal rainfall [moving forward] it should be okay but if it does continue it could be dry."

Federated Farmers president Will Foley said the figures reflected that, unlike much of the North Island which had plenty of rainfall, southern Hawke's Bay was the "odd one out."

"It's just at that tipping point where we know we could go dry and enter a dry spring and early summer or keep getting rain and it carries on to be a good spring."

He said it was too early to speculate on how dry conditions would get during the summer, but added farmers were generally happy after excellent lamb survival this year and hoping spring conditions would support that.

"Without official numbers coming in it looks like there's going to be a lot of lambs on the ground so one thing farmers will be looking for is a good spring with plenty of grass growth to fatten them up."

Metservice meteorologist Ravi Kandula said today would bring southerlies to the region, spreading up the east coast with showers and easing in the evening.

"We then have light winds on Friday with fine spells and possibly an afternoon shower or two. A mainly fine day though."

Mr Kandula said Hawke's Bay would be affected by an intense weather feature in the southern part of the South Island, which would bring northerlies and high cloud on Saturday, and increased winds with scattered showers on Sunday.