When we hear that there's a 50% chance of rain, it's often hard to know exactly what that means. Do I need an umbrella or not? In this TikTok, broadcast meteorologist holthanley
explains what "chance of rain" really means, and it's even more convoluted than you might think.
I had always believed that chance of rain meant literally that: the odds that it was going to rain. A fair assumption right? More recently however, I learned that part of the calculation has to do with the probability that rain will hit your location, even when there's rain in the area. It turns out, the real chance of rain is a multiplication of those two numbers.
A 50% chance of rain, and another 50% chance that the rain hits my location? It's a 25% chance of rain. As convoluted as this sounds, it is the most accurate way to express the odds that any one location will receive rain. Still, they could have come up with a term that better represents the formula.