Strong El Nino to bring U.S. warmer winter

People run on the street in downtown Chicago, the United States, on Dec. 9, 2015. The U.S. National Weather Service said there is a 70 to 80 percent chance the average temperature in December will be above normal for the Midwest due to a strong El Nino. In Chicago, the average temperature is 27.7 Fahrenheit degrees in December and the average temperature in December this year could be 5 to 7 degrees above normal if current forecast models hold. (Xinhua/He Xianfeng)