I agree with Johnny. 'Time is drifting' sounds very nice, and is a good phrase to use if you want to be poetic. It's an evocative image, suggesting the slow movement of water or snow. It would be fine in a piece of creative writing. Otherwise, it might be better to use a more everyday word such as 'passing'.

It could be, depending on the context. Sounds like 'time is moving slowly' to me. We often use the expression, 'time flies' to say that time moves very quickly. 'time is drifting' sounds very poetic.

what about "time is flowing"?