There is the question, I do not have the answer.

This morning was a torrential downpour with no wind surprisingly. Since the rain was falling straight down, I thought I wouldn’t have a problem staying dry. I was wrong. By the time I reached the bus stop, the back of my pants from the knee down were soaked through.

I believe I am holding the umbrella correctly. I use a medium-sized umbrella. I hold it at below-chest height about five inches away from my body.  My estimate is the umbrella provides a two foot radius of protection. I am of an average build, so no portions of my body are sticking out.

Yet, for no apparent reason, my pants are usually soaked through.  I need enlightenment. Google has failed in providing me with the answer.