Weather gurus generally define a heat wave as several days of temperatures that are 10 degrees or more above average, often accompanied by high humidity.

The American Red Cross says people in areas prone to heat waves should plan ahead, especially if they care for infants or the elderly.

Here’s what the organization suggests:

• Pay attention to the local weather forecast.
• Stay in an air-conditioned place. If no air conditioning is available at home, keep a list of nearby cooling centers.
• Create an emergency kit, in case there’s a power outage.
• Never leave anyone or a pet in a hot car, even with the windows open.
• Make sure pets have enough water, food and a cool, shady place to stay.

Source: HealthDay