Sometime back in China I saw a simple solution to biking in the rain without the pain of getting wet or letting your bags or any other form of luggage get wet. It was a perfect answer to commuting in the rain. It was something like a raincoat just that the front part was extended to the handle bar and it had a little clip to clamp it to the handle making a small canopy to cover the entire front part of the bike. There was enough space for a kid to sit without getting wet. This whole thing cost hardly 2 US dollars.
With this simple solution one doesn’t need to bother about umbrellas anymore. (Pictures are on their way)