The heat is returning to southern Ontario.
Environment Canada has issed a heat warning for Hamilton and Toronto - but not Niagara.
A hot and humid air mass will make its way into the area for the weekend into Monday. Daytime maximum temperatures of 31 degrees are expected along with overnight low temperatures of 20 degrees, providing little relief from the heat.
Meterologist Rob Kuhn tells CKTB it's called the 'urban heat island effect' where the large cities tend to be warmer during the afternoon.
A heat warning is called when the temperature reaches 31 for two days.
In Niagara it will be 30 today and 29 Sunday.