Catastrophe data company Perils has lowered its estimate for insured losses from April’s Tropical Cyclone Seroja to $394 million while saying it “serves as a warning” for the northwest of WA of the potential for devastation from tropical cyclones.

The Zurich-based firm’s second estimate for the event, which crossed the WA coastline unusually far south in April, compares with an initial figure of $434 million. Most of the damage resulted from the strong winds with only moderate rainfall.

The estimate is primarily composed of property losses, with motor losses representing just 1.4%.

Perils Asia-Pacific Head Darryl Pidcock says the loss impact of Cyclone Seroja would have been far greater had the storm crossed further south and made a direct hit on the town of Geraldton.

“As such Seroja serves as a warning that devastating tropical cyclones can happen in the northwest of the state of Western Australia,” he said.

WA hasn’t experienced a comparable loss since the 2010 Perth hailstorms, and a number of damaging cyclones in the 1970s, including Cyclone Joan in 1975, Alby in 1978, and Hazel in 1979.

Seroja made landfall just south of the town of Kalbarri at 8pm on April 11 and affected around 800km of the mid-west region coastline with strong gusts extending inland as the cyclone continued a south-south-easterly track into the morning of April 12. The town of Kalbarri was most affected by the winds with reported gusts up to 170km an hour.

Many other locations in the region, where properties are not built to withstand cyclones, experienced gusts above 125km an hour.

Perils’ loss number covers the property and motor hull lines of business. It usually has a $500 million reporting threshold but monitored claims activity for Seroja due to a high level of interest in the cyclone, which was unusual from a meteorological and insurance perspective.

A phenomenon known as the Fujiwhara effect caused Seroja to interact with nearby Cyclone Odette, pushing it south so it made landfall at an unusually strong intensity for the latitude.

“The prominence of the event in local and international media led Perils to make an exception to the standard reporting criteria,” it said.

This is the last Perils report for this event.