 So use caution if you're planning to be outdoors. Drink plenty of fluids. Stay in an air-conditioned room. Stay out of the sun and check in with relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose-fitting clothing. Take action when you see the symptoms of heat exhaustion and heat stroke. Heat stroke is an emergency and that will require an immediate call to 911. Know the symptoms of heat illness and heat stroke.