With temperatures expected to rise around 30 degrees celsius, Environment Canada has issued a heat warning for parts of northwestern Ontario.
The affected areas include Dryden, Kenora, Fort Frances, Emo, Rainy River, Pikangikum, Red Lake and Sioux Narrows.
The warning is in effect from Thursday afternoon through Friday night, with daytime highs expected to reach between 28 and 32 degrees.
Overnight lows will remain warm, ranging from 18 to 21 degrees, offering little relief from the heat. Humidex values are forecast to reach 36.
The agency is reminding residents to take precautions, especially those who are more vulnerable to heat-related illness.
This includes older adults, people living alone, young children and individuals with chronic health conditions.
Health officials recommend checking in on neighbours and loved ones regularly. Early signs of heat exhaustion include headache, dizziness, nausea, fatigue, thirst and dark urine.
Anyone experiencing these symptoms should stop activity, move to a cool place and drink water.
Heat stroke is a medical emergency. Symptoms may include red, hot skin, confusion, nausea and loss of consciousness.
If someone shows signs of heat stroke, call 911 and try to cool the person with cold water or ice packs while waiting for help.
To stay safe, residents are advised to stay hydrated, avoid strenuous activity during peak heat, wear light clothing and seek out cool or shaded spaces.
If your home is too hot, consider visiting a public place such as a library, community centre or cooling centre.
With temperatures expected to remain high through Friday, residents are reminded to look out for one another and take steps to stay safe during the heat.