Today is certainly not a picturesque summer day with the dull grey skies, and according to the experts it's about to get a whole lot worse. 

Environment Canada issued an alert this morning, saying there's a potential for heavy thunderstorms this afternoon. Rainfall is expected to be between 30 and 50 mm, but some parts of the city could get hit harder.

Following the thunderstorms, however, is another beast entirely. 

We will be warmer than ALL of these places, this weekend in S. ON. AHHHHHHHHH that is all. #onwx #extremeheatiscoming pic.twitter.com/PkG0cyH7Hv

— Saphia Khambalia (@SaphiaTWN) June 27, 2018

The showers will not make way for flowers, but for an extreme heat wave that does not currently have an end date in sight. 

Beginning on Friday or Saturday, and throughout the Canada Day long weekend, expect daytime highs in the low-to-mid 30 degree range, but it'll feel like it's about 43 C. 

"There is still uncertainty regarding when the heat event will come to an end," reads the Environment Canada bulletin. "Current indications suggest the heat could persist into the middle of next week." 

The government body says it will likely be "the most significant heat event of the season thus far." Expect more frequent heat-related announcements as the end evening draws near.