Where I live, its common for it to be stupid windy much of the time - a consequence of being stuck way out in the North Atlantic I suppose. But anyway, just stopped in traffic on an otherwise warn sunny summer day, I could be experiencing wind gusts between 35 - 45 mph. Once you get going along in traffic add to that the effect of the car's speed, and you can get why I like to have the windows up while the top is down.
And when there is no wind, folks are like Keanu and say "whoa".
