Reuters: The summer of 2013 has been another severe fire season for the United States, a trend that has insurance companies bracing for a new normal: higher rates of property damage as Americans move to wildfire-prone areas in ever greater numbers. The deaths of 19 firefighters in Arizona’s Yarnell Hill fire in June, the biggest such loss since 1933, shocked the nation and was the most visible evidence to date of a general trend of rising threats to lives as well as property. The insurance industry has…