The Boston Marathon is held in any kind of weather and that makes the forecast for runners and spectators extremely important. Marathon Monday is uniquely Boston. You've got the most elite runners from around the world racing to the finish line on Boylston St while the crowd roars at Fenway Park.

A week out from race day, forecasts from the Weather Channel and Accuweather both show conditions decent for marathoning.

Weather means everything on race day and people really need to be aware of the impact on runners,” said Dr. Frank Colby, professor at UMass Lowell’s department of environmental earth and atmospheric science.