(section in progress)
To have one’s head in the clouds
Fig. to daydream; to be unaware of what is going on from fantasies
Every cloud has a silver lining
Prov. You can derive some benefit from every bad thing that happens to you
To be under a cloud
Fig. to be suspected of something
A cloud on the horizon
Fig. a problem or difficulty which you expect to happen in the future
To live in cloud-cuckoo land
Fig. to believe that things you want will happen, when really they are impossible
To be on cloud nine
Fig. to be very happy