While it is too early to put a figure on damage caused by tornadoes that continue to rip through the U.S. midwest, insurers are bound to face a stiff price tag. The tornadoes have killed at least 40 people, and are being declared a catastrophe by the Insurance Services Office (ISO). This means that a minimum US$25 million in insured damages are expected. However, a much higher figure than this can be expected. Starting last Friday, the tornadoes hit at least 14 states. The event was sparked by a “clash of dry air from the Rocky Mountains and warm, moist air off the Gulf of Mexico”, reports AIR Worldwide Corp., a catastrophe modeling company. Tornadoes, hailstorms, thunderstorms and windstorms have resulted, and even more severe weather is expected through this week.