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Thunderstorms cost US insurers $4 billion

Eight spells of severe thunderstorms last month left US insurers with a bill exceeding $US3 billion ($4 billion), Impact Forecasting says in its monthly catastrophe recap.

Economic losses from widespread convective storm and flood damage are expected to reach $US4 billion ($5.4 billion).

Elsewhere, insurers in Japan will pay out at least $US125 million ($169 million) for claims arising from a 5.5-magitude quake in Osaka prefecture, the Aon Benfield subsidiary says.