In the midst of Toronto's most recent heat wave, the city has extended its heat warning and opened seven centres where residents can cool off. Seven public pools will be open late as well. The summer heat will continue on Sunday with temperatures expecting to reach the low 30s. The forecast high on Saturday was 33 C, but it felt more like 38 C with the humidity. The UV index is very high. "The mid-summer heat episode will continue today with temperatures once again soaring at least into the low 30s this afternoon," Environment Canada said in a release. "Temperatures tonight will likely drop to the upper teens in most areas, providing some relief from the heat ... Temperatures Sunday and next week [will remain] quite warm, but just below the heat warning threshold." During an extended heat warning, the medical officer of health recommends people visit family, friends and neighbours, especially isolated adults and seniors, to make sure they're cool and drinking lots of fluids. Also at risk of heat-related illnesses are people with chronic medical conditions, limited mobility or mental health problems, as well as infants, young children, people on certain medications and the homeless. Residents can also cool off at air conditioned shopping malls, libraries and community centres. And landlords of buildings without air conditioning are encouraged to have a dedicated cooling room for vulnerable residents.