The phrase "mind-blowing" gets thrown around a lot on the Internet . . . but this truly deserves it.
There's a TikTok videogoing viral right now from a woman who said she just found out the "chance of rain" in a weather forecast doesn't mean what we have always thought it means.
30% does NOT mean there's a 30% chance it's going to rain.
That 30% is based on what the chances that it's going to rain are multiplied by the percentage of the area that will get the rain.
So "50%" in the forecast doesn't mean there's a 50-50 chance it will rain. It means there's a chance rain will happen in the area, multiplied by how much of the area will probably get that rain.
So if a meteorologist is 50% sure there will be rain that will cover 80% of the local area, that would come out as . . . 40% on the weather forecast.