A girl's room is left exposed in the devastated town of Pleasant Grove, Alabama, after the deadliest of 343 tornadoes that touched down from April 25-30 killed 78 people in northern Alabama.
Eleven twisters in the system reached category EF4 and four were rated EF5. In all, 321 people died. Total damages exceeded $10.2 billion, making it the most expensive calamity in a record year for U.S. disasters.
NOAA tracks inflation-adjusted billion-dollar disasters as a way to evaluate the intensity of the storms, droughts, floods and fires that strike every year. Two storms that are likely to be added to NOAA's list: the East Coast Halloween snowstorm that fell on autumn leaves and Tropical Storm Lee, which temporarily curtailed 61 percent of oil production and 42 percent of natural gas output from the Gulf of Mexico.
From 1990 to 2009, tornadoes caused $97.8 billion in insured U.S. losses, second only to hurricanes, which were responsible for losses of $152.4 billion.
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