What does the percentage of rain mean, and how does it work?

In this article, we’ll answer the question, “What does the percentage of rain mean?”

So today, after this article, you will understand the numbers on your weather app and what the percentage of rain means.   

What does the percentage of rain mean?

It means that a certain percentage within the forecasted area will see rain. So if you see an 80% chance, 80% of the forecasted area will see rain. 

But Meteorologists don’t agree on how to measure the Probability of Precipitation. (the percentage of rain that your weather app is showing)

Some use a formula to show the percentage of rain called PoP = C x A

C = Confidence 

A = Area 

So when counting out the percentage of rain, they multiply Confidence by area. 

Example: If there’s a 50% chance of rain in a 40% area, the probability of rain becomes 20%.

It’s common that meteorologists to measure PoP “Probability of Precipitation” as the chance of rain at any provided moment in the area they cover during a certain period.

It’s so close as they can get to the definition National Oceanic and Atmospheric Administration (NOAA) shares on their website on Weather Education.

Weather Expressions

ISOLATED 10% to 20% You’re lucky if you even see any rain

SCATTERED 30% to 40% A few showers in the mid-south 

NUMEROUS 50% to 70% Rain for the majority of the area 

WIDESPREAD 80% to 100% Prepare for a total soaker

Summary percentage chance of rain meaning

I hope you enjoyed this guide on answering the question of what percentage of rain means. 

As you discovered, understanding the meteorologist on your tv or what your weather app is showing isn’t so hard. 

You also learned how to calculate the chance of rain by using a simple formula. 

So the next time you got a party planned outside, and it shows 90% of rain, it might be a good idea to postpone. But if it shows 25% of rain, you can probably go for it.