Summer officially arrives at 6:07am Thursday, but whether the next couple of months will be hot and sticky or cool and wet across southwestern Ontario remains a bit of a mystery.
Environment Canada expects the next four weeks will be hotter than normal with above seasonal daytime temperatures across the region. A clearer picture beyond that timeframe has yet to emerge though.
"There are equal chances of above seasonal, below seasonal, or at seasonal temperatures for the whole summer," said Environment Canada Meteorologist Gerald Cheng.
The average daytime high for this time of year is 24 C.
The forecast for the first day of summer calls for sunshine and a daytime high in the mid-20s before things cool off for the weekend.
The uncertain summer weather comes on the heels of a spring that was a bit of a mixed bag.
"Who could forget the massive ice storm in April and the wind storm in early May," said Cheng.
He went on to note this past April was the coldest southwestern Ontarians have seen in over 40 years.
"We have to go back to 1975 to see a similar April, so that is a really long time," said Cheng. "But on the contrary, in terms of the temperatures in May it was one of the warmest. We have to go back to 1911 to see a May that was even warmer."
The average temperature in April was 3.3 C, while the average daytime high in May was 16.8 C.
With ten days to go, June has proven to be relatively normal temperature-wise, with the average daytime high sitting at 18.5 C.