Multiple severe weather outbreaks in the US, including tornadoes, hail, and flooding, resulted in billion-dollar insurance losses in March, Aon’s latest Global Catastrophe Recap report says.

A total of 122 tornadoes touched down in the US last month, the most since 2017 and killing at least seven people in Tennessee after numerous rivers swelled beyond their banks.

March brought the first US EF4 tornado for the year on the Enhanced Fujita scale – in which wind speeds can reach 322 kilometres an hour – and there were also four EF3 tornadoes, which can bring speeds of up to 266 kilometres an hour.

The severe weather was most damaging across Alabama, Mississippi, Texas, Georgia, and Tennessee, with hundreds of reports of large hail and damaging straight-line winds that resulted in extensive property damage.

A cost of nearly $US2 billion ($2.63 billion) is expected, with insurers likely to see losses of more than half that cost.

In Australia, NSW had its second wettest March since 1900 and extensive flooding across parts of the east coast killed two people and inundated thousands of properties as well as impacting infrastructure and agriculture.

In Europe, windstorms Klaus and Luis struck Germany, Belgium, the Netherlands, France and the UK. Local insurers were faced with tens of thousands of claims.

“While the 2020/21 European windstorm season was not abnormally costly, it remains a peril worth closely monitoring,” analyst Michal Lörinc said.

In Colombia, persistent seasonal rains and severe weather led to a public calamity being declared in the Valle del Cauca Department due to damage to roadways, homes and crops.

In Algeria, flash floods affected more than 500 families, leaving 10 people dead or missing.

In Mongolia and China, severe sand and dust storms killed at least 21 people and millions of livestock, and destroyed hundreds of yurts.