A woman fends off the last blast of winter and the flu season in Philadelphia this month.
March 8, 2013 Why do people in Boston get the flu when it's cold, while people in Senegal get sick when it's hot? Humidity is a big part of the explanation. But how flu spreads in the tropics and more temperate climates appears to be different.
On Monday, a weed was growing through the dry earth at Marion Kujawa's pond, which he normally uses to water the cattle on his farm in Ashley, Ill.
Scott Olson/Getty Images
July 17, 2012 "Moderate to extreme" drought conditions already exist in about 55 percent of the continental U.S. No relief is in sight. There are warnings this could be one of the 10-most expensive weather disasters in U.S. history.
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