Does anyone know how to guess the weather?

I don't believe in umbrellas -- not that they don't exist. I'm quite sure they do exist, but I just can never feel like carrying it around just in case seems like a good use of my available digits. It must be my experience in cities like Pittsburgh and Chicago, where if it rains, the wind usually kicks up with such ferocity as to render an umbrella inside out. And after destroying enough umbrellas in my youth, it seemed like just wearing a nice somewhat waterproof jacket was just as good. And realizing that the semi-permeable membrane of my epidermis still managed to keep out most of the water. So, I'm mostly interested in trying to figure out when I'll get caught in a torrential downpour in New York. Just for my edification, I guess. I suppose I could look at the weather forecasts, but that always seems to be like cheating.