I remember on a road trip showing up at an almost empty parking lot at Camelback mountain, middle of the afternoon, bon an extremely hot summer day. There was a ranger in the parking lot who approached me and started asking me questions and talking to me about the heat. His job was to make sure people were prepared for the hike and try to dissuade them. Once he saw I had a bladder hiking shoes etc he was satisfied and told me be careful have a good hike.