What will Bay of Plenty weather be like this summer?

A meteorologist says this summer will bring many warm beach days for Bay of Plenty residents. Photo / Andrew Warner

Plenty of "warm, humid, beach days" and "muggy nights" will most likely be in store for the Bay this summer, a meteorologist says.

And there was "good news" for farmers and the agricultural sector who had suffered through some "very dry summers" recently, as soils were currently "sufficiently moist".

Niwa meteorologist and forecaster Ben Noll said the Bay of Plenty would most likely have above average temperatures and near normal rainfall. Dry spells would be interspersed with occasional heavy rainfall.

Federated Farmers Rotorua/Taupō provincial president Colin Guyton said a hot, dry summer was always a worry but he was "pretty used to it", with the past three summers having been "quite hard".

But he had planned for this feed-wise by having "plenty of silage" and by planting a summer turnip crop which would give him "bulk, good-quality feed" in February and March.

Guyton said there was not a lot of sun in September so "the grass had no guts in it", or in other words, was "low in energy".

Federated Farmers Rotorua/Taupō provincial president Colin Guyton. Photo / Supplied

He said it got "quite dry" in November but "significant rain" in mid-December meant "things were looking reasonably good from a feed point of view". This meant the ability to feed cows well until about the end of January, he said.

"Obviously hot weather does mean that the cows can suffer from a bit of heat stress and so it's always a good idea for us to use paddocks with plenty of shade in them on hot days."

Rotorua Kayaking owner Bradley Lauder said the biggest thing that affected them was the wind, but in January the wind usually "calms down" and it was easier for people to get out on the lake and go kayaking and swimming.

Temperatures in Rotorua could get up to 27C or 28C in January and February, so if it got even hotter, people would be "really searching for cooler water".

Lauder said this would likely be Lake Rotoiti because it was a deeper lake and more sheltered.

University of Waikato chairman in coastal sciences Professor Chris Battershill said "more sunlight hours" meant any seaweed, particularly sea lettuce, would "bloom".

If there was an on-shore wind, sea lettuce could blow up on beaches in "quite significant piles" which rotted pretty quickly and produced a raw, stale egg smell, he said.

It also made fishing "difficult" because lines were not down very far before it got "wrapped up in sea lettuce" which hid the bait.

MetService meteorologist Lewis Ferris said La Niña could bring warmer overnight temperatures and humid daytime conditions to the Bay this summer due to increased wind flows from the northeast.

La Niña was the "sister" of El Niño, which were opposing phases of the El Niño Southern Oscillation.

La Niña was a climate driver that impacted trade winds across the equatorial Pacific Ocean and impacted sea surface temperatures. This had a flow-on effect for weather in Aotearoa, he said.

December was the wettest month in Rotorua last year. Photo / Andrew Warner

On the weather last year, Ferris said December was the wettest month in Rotorua last year, with about twice the rainfall that was considered average. This was about 182mm as of December 20.

January 26 was the warmest day last year at 28.9C and August 10 was the coldest morning at -2.3C.

The yearly mean temperature last year was about 13.3C which was "well above average but not record-breaking". It was similar to the past five years, Ferris said.

According to Niwa's seasonal summary, spring 2021 was New Zealand's warmest spring on record, with the Bay of Plenty recording "pockets of well above average temperatures". This meant temperatures were more than 1.2C above average.

At the end of November, soil moisture levels in the Bay of Plenty were "below normal" according to the same report.

"Near average" temperatures were recorded in the Bay of Plenty for both winter and autumn last year.