Boston Marathon forecast calls for warm temps, light breeze

The Boston Marathon, a yearly test of endurance on Patriots' Day, throws more than just physical demands at runners. New England's unpredictable weather adds another hurdle.

While runners train for anything, most crave cool (45-50 degree temps), overcast skies, moderate humidity and a light tailwind. This minimizes heat stress, allows comfortable clothing, and provides some sun protection.

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Hoping for perfect marathon weather here is like predicting a snowy Boston Christmas – a gamble. April is known for cool dampness, but also sudden swings, rain, snow and strong winds.

Weather significantly affects runner performance:

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Heat and Humidity: Dehydration, fatigue and heatstroke are dangers for unprepared runners.
Cold Temperatures: Stiff muscles make it harder to maintain pace.
Strong Winds: Increased resistance and fatigue can impact pace and strategy.
Rain: Manageable with proper clothing and preparation.

Thankfully, this year’s forecast is going to cooperate, though it will be on the warmer side for runners. Temperatures in the morning at the start line in Hopkinton will be around 50, with some low clouds possible in the early morning.

Those clouds will break and give way to sunshine, which will be out in full force for the remainder of the day.

Temperatures will rise through the 50s and into the 60s fairly quickly, topping out in the middle 60s in most cities and towns along the route. There is no precipitation to worry about. A light northwest wind is anticipated in the morning, which will kick up a bit more along the course, about 7-14 mph.

This quartering tailwind will provide a slight push for runners. That said, there is a chance the wind lets up a bit, allowing for a light seabreeze or east wind to kick in near the finish line – particularly for those runners that may cross later in the day.