Toronto's first big heatwave of 2013 came to a tempestuous end this evening with a spectacular cluster of thunderstorms. As the rain cascaded down (no floods this time, thankfully) thousands of you turned your cameras skyward to capture the end of what at times felt like interminable heat and humidity.

Unfortunately, it seems a substantial portion of the Leslieville tree that inspired Alexander Muir to write the song "The Maple Leaf Forever" seems to have fallen victim to the weather. Toronto Hydro is reporting a scattering of outages across the city, but otherwise Toronto seems to have come off nicely unscathed.

Soon after the rain shut off, large parts of Toronto were treated to an impressive rainbow and some rather unique "mamma" clouds. According to my trusty Cloudspotter's Guide, mamma, sometimes "mammatus," form on the underside of anvil clouds and are associated with particularly severe storms.

They indicate a high level of instability in the air near the top of the cloud and are so named because they look, well, like boobs. How mature.

Rejoice, everyone. This weekend might actually be pleasant. Here are some of the best social media shots from the heat wave slayer of 2013. Stunning lead image by rhyshastings.

For more shots of the stormy skies and the wild clouds, check out our #stormcloudsTO stream.

Chris Bateman is a staff writer at blogTO. Follow him on Twitter at @chrisbateman.