CHICAGO (AP) -- Authorities say the number of heat-related deaths in the Chicago area has risen to 18, despite the cooler temperatures.

The Chicago Tribune reports the Cook County medical examiner's office determined Sunday that eight more people died from heat-related causes, adding to the 10 deaths previously confirmed Saturday.

Chicago saw three consecutive days of triple-digit temperatures in the past week.

The newspaper reports that heat wave that affected two-thirds of the nation has tied or broken nearly 3,400 maximum and minimum temperature records.

Among those included in the area's heat-related deaths are a 100-year-old woman, 65-year-old woman, a 53-year-old man, a 46-year-old woman and an unidentified man believed to be about 30 years old.

The National Weather Service is predicting cooler weather for the next few days.