Heather’s Weather Whys: What does a 30% chance for rain mean?

When you look up the forecast on your phone, you usually get rain chances as a %. Do you know where that number comes from? Better yet do you know the difference between a weather app that is run by a human and one that is only run by a computer?
The answer to those questions in this week's Heather's Weather Whys!

[@thebinding]

Finally I know what 30% of rain means

[@yackawaytube]

The solution is to report 2 numbers, instead of saying 30% chance of rain, just say "50% confidence that 70% of the area will get rain", or shorten it to 30%/70% confidence-area ratio. See how easy that is?

[@jerbsherb4391]

The public is already stupid and confused with numbers. Giving out that much detail would fry their brains lol

[@tonycarboni2002]

There's a 99% chance you are right.

[@bojack-horseman]

i would much rather see the two numbers separately

[@meherenow793]

50/50

[@ANIKETSINGH-yz2mg]

Now, I get some knowledge about it....

[@sajjadhoviegar5950]

Isn't it better to see both values so we can interprete the probability and area better?

[@user-bs8gm1lh4c]

dont we also have to rely on the radar too?

[@tonycarboni2002]

There's a 100% chance that 90% of people don't understand this. So, 95% chance of rain?

[@geoffreylee5199]

Yo Heather, start giving occasional degrees Centigrade in reports; that’s a true geek Stateside …

[@ANeal-xj2eq]

You can use machine learning from former years and storm events to construct a more accurate prediction is what might happen.