What are the signs of heat exhaustion and heat stroke?

Health Canada lists these.

Heat exhaustion: elevated body temperature, confusion and poor coordination, skin rash, muscle cramping, lightheadedness or fainting, queasiness or vomiting, profuse sweating, headache, fast breathing and heartbeat, intense thirst, and dark urine with less frequent urination.

Heat stroke: elevated body temperature, confusion and poor coordination, dizziness or fainting, and no sweating with very hot, red skin.

Health Canada also says people with breathing difficulties, heart problems, mental illness, hypertension or kidney problems are at higher risk, and that infants and young children are likely at higher risk because of their physiology and dependence on caregivers.