"In some places, sea temperatures are already around three degrees higher than usual, which strongly suggests summer weather conditions are going to be far from normal."
It was predicted that warmer waters will make it easier for tropical lows to sweep southward and affect New Zealand, exposing northern parts of the North Island to increased flash and river flood risk through summer, especially in 2022, and autumn.
AMI's weather analysis also predicted the east coast of the South Island would have an increased risk of late-season heavy rain, with hotter than normal temperatures also expected in the Canterbury and Otago regions.
Hail events, although rare, looked to have slightly elevated risks as well.
"We're predicting an increased wildfire risk in areas to the east of the Alps, predominantly due to warmer than usual temperatures creating excellent conditions for wildfires – including producing plenty of fuel in the form of dried-up vegetation," Buckley said.
"Compounding this problem are the high-pressure systems expected to sit east of New Zealand over summer and continuing into autumn, increasing the number of northeasterly wind regimes and further contributing to the types of conditions that help wildfires spread rapidly once they start."
Last month, the Insurance Council revealed how one storm that swept across the country in mid-July caused enough damage to cost around $122m in claims.
The storm left a raft of damage across much of the country, with severe flood damage in Westport, as well as slips and flooding through the upper South Island, Wellington and North Island.
Combined, there were 3790 claims for house and contents, 795 commercial and business-related claims and 590 claims for motor vehicles.
In Westport alone, insurers met more than $85m in losses, the council's chief executive Tim Grafton said.
"This year severe weather has affected many of our communities, with the impacts of climate change being felt by many, with severe weather becoming more frequent and more severe."
