Dog days of summer are upon us, and that means extreme high temperatures are likely. When we talk about the high heat we throw all kinds of heat-related terms around, but do you know what they all mean?

Heat wave. We probably all recognize this one: a prolonged period of time of excessive heat. Combined with excessive humidity it can be brutal.

Heat index. This tells us in degrees how hot it feels when humidity is added to the air temperature. With full exposure to the sun, this can increase the heat index by 15 degrees.

Heat cramps. These are caused by muscle pains and spasms during exertion. This is your first sign that your body is having a hard time battling the heat.

Heat exhaustion. This occurs when body fluids are lost through heavy sweating. If not treated, the condition can worsen and the body temperature will keep on rising.

Heat stroke. This is a life threatening condition when you can no longer sweat to cool the body. The body temperature can rise so high that brain damage and death can result if the body is not cooled quickly.

Sun stroke. This is another term for a heat stroke.

Excessive heat watch. Conditions are favorable for an excessive heat event in the next 24 to 72 hours. Generally, this means outside temperatures are 105 to 110 degrees Fahrenheit.

Excessive heat warning. Heat index meets or exceeds local warning criteria for at least two days.

Heat advisory. Heat index is forecast to meet local defined criteria for one to two days: 100 to 105 degrees Fahrenheit.

If you must be outside during these hot summer months, avoid strenuous work during the warmest part of the day. Take frequent breaks when working outside.

Wear loose-fitting, lightweight and light colored clothes. Dark colors can absorb the sun’s rays. A wide brimmed hat can help to protect and keep you cool.

Consider changing the time and day of outdoor games and activities. Wear sunblock when outside. Most of all, stay hydrated!

Remember heat can kill by pushing the human body beyond its limits. In extreme heat, the body must work extra hard to maintain a normal temperature. So listen to your body and be careful in the heat.

Cinda Seamon is the fire and life safety educator for the Town of Hilton Head Island Fire & Rescue.