415!!! Holy crow, that's bad!!
This past summer we had some days in the 150s and that was so bad for me I started coughing so hard I almost passed out. I have a mask now for when the days get that bad. We have a lot of fracking and other oil pollution here, and the mountains being so close can sometimes trap it and we get "the brown cloud." But it's really bad when there are wildfires added in to the mix. :( Just a couple of days ago the oil refinery had some kind of incident where it released a brown greasy substance into the air and schoolchildren a mile away were told to stay inside. When they were allowed to go home, the teachers' cars in the parking lot were all coated in the stuff. The refinery said it was "safe," naturally.
But still, even with all our problems I've never seen us go over 200 let alone 400!! I can't imagine. :(