We’re in for some September heat.

Environment Canada has issued a humidex advisory  for Toronto and parts of southern Ontario.

As hot and humid air moves into the area  from the American Midwest on Tuesday, temperatures are expected to reach the low to mid-30s with humidex values in the 40s.

The humidex advisory comes with a warning that Tuesday may feel like the hottest day of the summer.

On Wednesday, humidex values will likely remain near 40.

The weather office says temperatures are expected to return to near seasonal values by Thursday.