If you're deciding whether to dress and prepare for rain you're more curious about whether it will rain or not than the amount.

The two things are not strictly related, you could have 30% chance of heavy rain, or 90% chance of light rain. Both are needed and many apps have both.

https://weather-sense.leftium.com shows both mm/hr and percentage chance.

I've noticed there is a correlation, but having both is useful:

- Often there is a percentage chance, but the mm/hr is 0. At these times, it could rain but will probably be very light.

- Less common, but sometimes there is 0% chance, but a non-zero mm/hr.

Chill a bit with the spamming ;) (7 times in this one post currently)

mm/hr is more useful for areas that get lots of rain. When I was living in Seattle, chance of rain was meaningless but mm/hr made the difference between being able to do an outside activity or not. In California, chance of rain makes sense because it rains very little.

Most places I look at report both probability and give a measurement prediction.

So it would be like "60% chance of rain after 2pm, total amount less than 1/10th of an inch"

Meteoswiss has timeserie histogram with of amount of rain with confidence intervals (10th and 90th quantile)

It tells you all you need to know at a glance :)

e.g. see https://www.meteoswiss.admin.ch/images/1904/website/weather/...

(from https://www.meteoswiss.admin.ch/weather/weather-and-climate-...)