A heat advisory is in effect through 8 p.m. Thursday from the southern interior of York County to northern Penobscot County.
The heat index, which combines temperature and humidity in calculating a "feels like" temperature, will be in the upper nineties. That increases the risk for heat exhaustion and heat stroke.
The National Weather Services is advising people to take precautions and be aware of the signs of heat-related illness, which include headaches, nausea and dizziness. Confusion and slurred speech are symptoms of heat stroke, which is a medical emergency.
Several dozen cooling centers are open across the state. The Maine Emergency Management Agency website has a detailed list.
