Why do most online weather forecasts only state the chance of rain as a percantage, without stating the expected rainfall in millimetres? If there’s a 90% chance of rain, it matters a lot whether it will be 0.5 or 5mm

Question

Why do most online weather forecasts only state the chance of rain as a percantage, without stating the expected rainfall in millimetres? If there’s a 90% chance of rain, it matters a lot whether it will be 0.5 or 5mm

In: 29

Answer 1

Let’s say it says 16% chance of rain.
This means 100% chance of rain for 16% of the designated area.

Edit: This is not correct