This happened in a fall of 2017 during rain which was heavy periodically. Everybody was moving through the slow traffic, but one car somehow missed it and rear-ended into another vehicle without even trying to brake deteriorating already bad traffic on highway.
Always remember to periodically monitor traffic from the opposite direction even if there is a very wide median like on most parts of Highway 404.
Unfortunately it’s not enough and people continue to die on Highway 404 when oncoming vehicles fly over the median due to some circumstances and crash into traffic moving up to 140 km/h.
About a year ago southbound car crossed highway ditch and slammed into northbound car killing 3 people. There were other fatalities happened on 404 earlier.
I was traveling southbound 404 during wintry morning last spring after ice pellets and freezing rain. Was driving pretty cautious in the second lane which probably saved me life. Suddenly white van moving northbound slipped into median ditch for the reason I don’t know. Maybe someone else caused such maneuver of white van.
Here is a video of this accident captured on dash camera:
