The very quiet can seem more salient than the very loud. But how?

I was walking to work and while crossing over the highway I noticed that the sound of traffic below me seemed quite loud, nearly overwhelmingly so, but, somehow, even more clearly over that I could hear the subtle, faint, sound of my hair brushing against my hood, and, even though I could hear it better, and more clearly, it simultaneously seemed quiet. Now: how is this so? How is it that the fainter, subtler, whisper-like sound of my hair brushing against my hood is capable of being heard more clearly, and over the sound of rush-hour traffic on an eight lane highway?