
How Hot Is Too Hot to Activity Outdoors in Summer?
When temperatures rise above 90°F (32°C), outdoor activity becomes risky, and once the heat index (temperature plus humidity) crosses 100–105°F (38–40°C), it is generally considered too hot for most people to safely exercise or spend long periods outdoors. At these levels, the body struggles to cool itself, increasing the risk of heat exhaustion and heatstroke….