A heat warning has been in effect for southern Manitoba to start the month of June, but last month was one of the hottest Mays on record.

Environment and Climate Change Canada's Natalie Hasell looked back at Portage's history for the fifth month of the year.

"The monthly mean temperature was 15.7 degrees Celsius, so that's taking daytime and nighttime temperatures averaging over the month," says Hasell. "The normal standard average is 12.4, meaning the difference from normal was 3.3, making it the 2nd warmest May in 135 years."

Precipitation-wise, Hasell says it was the 25th driest May as we saw 38 per cent of the normal amount.

"This May, Portage reported 19.5 millimetres of precipitation," says Hasell. "Using the average, you would get 51.7mm. That 38 per cent is, I'd say, pretty significant even if the ranking is not. It is a May that is a little bit different than some other Mays that we've had."

It was a consistent heat that Portage dealt with, rather than a short heat wave. While the month as a whole was much warmer than normal, no specific day was hot enough to break a record.