site. during the heating of the day, those guys were baking in there. the experts say when it gets this hot we have to respect the dangerous power of the heat and do what s necessary to protect ourselves. the driving range at oakmark rec center was a hot spot loaded with golfers testing their swing and stamina in the heat. john had a smart strategy, in early, out early. i like to get here about 9:00 or so. it s very empty at that time. you can concentrate better and it s nice and cool. around 12:00 it s murder. reporter: blazing sunshine and clear skies all day meants air temperatures punching through the 90s and factor in the humidity and a pretty summer day becomes life threatening. it can happen very rapidly. reporter: fairfax health director gloria ayenzu says heat exhaustion and heat stroke are real concerns whether you re working outside or waiting for a bus and every type of american is at risk in this extreme heat. if you re someone who likes to exercise we