It'll be interesting to find out. I personally use rainviewer app on Android for rain notifications/radar. It's been hit miss so far, but generally the same as metoffice (but it has rain radar widget which is what I like)
The above link and rainviewer both have the same rain cloud heading in my general location. The linked app says there will be rain in 25 minutes but no one else does.
I like that you said "significant number" and your example was one person, you.