I wouldn't say conclusively, but certainly they're an indicator for things like what you mention. Nimbostratus are typically associated with rain, cumulonimbus for thunderstorms: both of these are indicators for the atmospheric conditions and thermal upwellings that will cause sudden precipitation and / or electrostatic discharge.

We also did air observations for pilots. If you saw certain types of cumulus near peaks, called lenticulars, pilots wouldn't go near them because they're caused by pretty dangerous winds dynamics.

It's all connected, which is why it gets so fascinating. Sadly, I never pursued meteorology beyond hobbyist, but I'd love to!