That’s the worst feeling! We had a similar scare a few months ago during that big spring thaw. It’s definitely not something you want to ignore, especially with the humidity we get here in the summer. We ended up calling for professional plumbing services windsor https://superiorplumbing.ca/windsor/ and they were incredibly helpful. The technician used a camera to inspect our sewer line and discovered that some tree roots had partially blocked the pipe, causing the backup during heavy rain. They cleared it out the same day and even gave us a maintenance plan to prevent it from happening again. They were very thorough and the pricing was very transparent. I’d definitely give them a call before the next storm hits!