One of the most important actions you can take during periods of extreme heat is to drink water, and plenty of it. Home air conditioning units are a great way to keep cool during extreme heat events, but not everyone has access to one. Even a few hours spent in cool temperatures can help you avoid heat illness. Extreme heat can prompt power outages or rolling blackouts as people crank up their air conditioning. Everyone’s heat tolerance varies, but prolonged exposure to extreme temperatures can begin to make you feel ill. Heat exhaustion is indicated by symptoms like heavy sweating, weakness, and digestive issues.