 Experts say prevention is key. That starts with drinking plenty of water. It's important to stay cool and to hydrate. Be sure to monitor for signs of heat exhaustion, such as heavy sweating, dizziness, fatigue, headache, and fast heartbeat. Donya back is CBS News, Los Angeles. After decades in business, the Mirage Hotel and Casino in Las Vegas is shutting down next week. The final day to stay overnight at the Mirage is Sunday. Jennifer Kuiper, CBS News.