A study of 1.8 million marathon finishers found that peak running speeds happen between 39 and 50 degrees, the exact range fall's first cold snap delivers.

It has been a while since a northern city has won the World Series. This year, two Midwest cities are in the running, but only one has to play home games outside.

When temperatures drop below 32 degrees Fahrenheit, freezing fog can coat roads in black ice and delay flights. Learn what it is and how to drive safely in it.

A seasonal clash takes place for the next week. Summer temperatures followed by the first taste of fall. Here’s the forecast.

The maps you need to monitor the tropics: One area to watch in the Atlantic, and Hurricane Simon in the Pacific.