The month of May has been unusually cold across northwestern Ontario, with temperatures as much as 5 degrees below average.

That will all change tomorrow, as a heat warning has been issued.

Barbara Lapido is a meteorologist with Environment Canada and says we can expect temperatures about 30 degrees Friday afternoon.

“Max temperatures in the area can reach up to 31 or 32 degrees, and the minimum temperatures Friday overnight into Saturday morning can be between 16 and 18,” explains Lapido.

“So, the minimums are going to be on the lower side, by the highs are going to be 30 and above.”

Lapido says although the system is widespread covering most of northwestern Ontario, there is not much humidity involved.

“In this case the humidex is going to be around 33. It won’t be that humid…very close to the high temperature…a little bit more like 33 or maybe 34 for some regions. The main actor in this case will be the max temperature.”

Lapido suggest the heat advisory should be short lived, extending into Saturday, but temperatures should moderate somewhat on Sunday.