Severe storms that swept across southern Australia at the end of October have caused estimated losses totalling $1.028 billion, catastrophe data company Perils says in a preliminary figure.

The storms impacted the Adelaide region on October 28, bringing heavy hailstorms and strong winds before moving into Victoria overnight and into the next morning, causing more damage as wind gusts of up to 146 km/h were recorded. The weather system also affected Tasmania.

“The losses to the insurance industry from the southern Australia severe storms were typical for this kind of spring storm in that they were generated by a combination of hail, wind and surface water flooding,” Perils Asia Pacific Head Darryl Pidcock said.

“The main cause of damage differed by region but was driven by the same low-pressure front sweeping across the three states.”

Perils says damage from the event is widely covered by insurance with losses mainly relating to property and motor, and contributions also from crop insurance, which is not included in the Perils survey.

Australia’s southern and eastern coastline endured a number of damaging weather systems during October ahead of the most severe of the storms.

“The event added considerable losses to an already challenging month for the insurance industry following severe weather outbreaks nationally in October,” Mr Pidcock said. “For the state of South Australia alone, the storm will likely be one of the costliest natural catastrophes ever.”

The group will put out its next estimate of losses on January 31, three months after the event.

Perils, an independent Zurich-based organisation providing industry-wide natural catastrophe exposure and event loss data, covers 17 countries including Australia.