 In Fairfax County, Scott Gellman, WTOP News. Now, D.C., Fairfax, Loudoun, and Prince George's counties say they have cooling centers open today, while other cities and counties say you need to head to your local public library to cool down. Public school system in Fairfax County canceling all outdoor activities today. D.C. and Arlington County have water spray parks available as well. Keep it right here on WTOP for your full weather forecast during traffic and weather on the 8th.