Hurricane Irene churned along the eastern seaboard for three days in August, creating havoc from Florida to Maine. The Category 1 storm left at least 45 dead across 17 affected states and caused flooding and extensive power outages-leaving 7 million without power at one point. Although the storm weakened from initial predictions, cost estimates for damage ranged from $7 billion to $10 billion, making it one of the 10 costliest disasters in the nation's history.