INSURANCE claims are likely to exceed $1 billion this summer after heavy rains lashed large parts of New South Wales on the weekend, adding billions of litres of water to already swollen rivers.
The Bureau of Meteorology issued a severe thunderstorm warning with a risk of flash flooding on Sunday for residents of the Hunter, South Coast, Northern Tablelands and parts of the Northern Rivers districts of NSW.
It came less than 24 hours after severe winds and rain hit hundreds of homes across Sydney and the Illawarra region, leaving towns in eastern NSW battling floodwater.
The latest figures from the insurance industry show claims for NSW, Queensland and Tasmania have jumped $150 million in the past two weeks, pushing the total value of insurance claims this summer above $830 million.
Figures from the Insurance Council of Australia show losses in Queensland have climbed to $661.3 million this year, with flood-related losses in NSW of $71.8 million. Tasmanian bushfire claims have risen to $87.1 million.
Insurers said they were expecting the total value of losses to grow in coming weeks, but it was too early to know how many fresh claims would be made after the weekend.
"It's not unusual for [claims] figures to balloon more than a week after [an] actual event," Campbell Fuller, Insurance Council spokesman, said. "We're not due to get some more figures until the end of this week."
The severe weather comes as QBE Insurance prepares to publish full-year earnings this week.
Last week, two of the country's biggest insurers - Suncorp and Insurance Australia Group - posted huge rises in six-month profit.
Suncorp saw net profit jump by nearly half, to $574 million, while IAG profits more than tripled to $461 million.
Insurance analysts said IAG's profit margin, which rose from 7.7 per cent to 19.2 per cent, was higher than they had ever seen.
It came in the same week that IAG, the group behind the NRMA, RACV and CGU brands, said its home and car premiums could rise by 5 per cent to 10 per cent this year.