Well, it's the 5th of September, and what do you know? Suddenly the length of time it takes to drive from home to work has almost doubled.
The difference? It's the start of the school year. The only conclusion it can be is that lots of students have cars, and drive in to college, or university, or that mothers/fathers drive their kids to school. Funny how parents and students are usually the most vocal group when it comes to complaining about the traffic, pollution, environment, etc.