The Philadelphia Marathon is under way. Temperatures at the start of the race were in the lower 20s with wind chills in the mid-teens despite the sunshine.
Organizers estimate that about 18,000 runners are winding their way through the streets. The course takes runners past such historic sites as Independence Hall, the Betsy Ross House and the Liberty Bell.
For those running or supporting someone in the race, preparation for the cold weather is key.
Even though there will be less wind Sunday than Saturday, any wind that does develop will drop the wind chills into the teens. The wind chill measures how much colder it feels against skin with a certain wind at a certain temperature so make sure you bundle up before and during the race.
The Earthwatch forecast is calling for a warmer day Sunday with temperatures approaching 40 degrees. So by noon it should be above freezing.
Doesn't matter if you're running or watching, you will need to take a few precautions to stay warm during and after the race.
Drink plenty of fluids even if you're not thirsty since you can become just as dehydrated (if not more) during cold, dry weather.
Dress in layers so you will be able to take off a few as you and the temperature warm throughout the race.
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