The combination of staggering heat and high humidity is expected to create a dangerously-high heat index today and tomorrow.

The National Weather Service in Wakefield issued a heat advisory on Monday for Suffolk and the surrounding area. The heat index is expected to be between 105 and 109 degrees today, with a maximum heat index of 105 tomorrow.

People should avoid being outside if at all possible, use their air-conditioning, drink plenty of fluids and check on relatives and neighbors.

If you must be outside, stay in the shade as much as possible, reschedule your activities for early morning or late evening and stay well-hydrated. Wear lightweight and loose-fitting clothing. Be aware of the symptoms of heat stroke, which include a lack of sweating, high body temperature, flushed skin, rapid breathing, racing heart rate, hallucinations and muscle cramps. Heat stroke is a medical emergency. Dial 911 and get into an air-conditioned environment immediately if you feel any of these symptoms.