Although it is one of the few subjects that we all talk about, how much do we know about the weather? Hopscotching through 100 meteorological milestones and insights, this illustrated overview touches on such varied topics as Earth's first atmosphere, the physics of rainbows, the deadliest hailstorm, Groundhog Day, the invention of air conditioning, London's Great Smog, the Year Without Summer, our increasingly strong hurricanes, and the Paris Agreement on climate change.