That heat warning for Muskoka is still in effect.

Environment Canada says you can expect another day of temperatures in the 30s with the humidity making it feel as hot as 43 degrees in some areas.

The agency says this heat wave, which is the worst one of the past few years, will last into tomorrow. Overnight, temperatures are only going to dip into the low twenties, giving you little to no relief from the heat. The heat is expected to break on Friday when a cold front moves in.

In the meantime, Environment Canada says you should never leave people or pets inside a parked vehicle. While extreme heat affects everyone, the risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors.

Environment Canada says you should watch for the effects of heat illness: swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions. Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.