Is describing rain as "nuwb" considered cursing time, knowing that the speaker intended it as a joke and used it to describe the weakness of rain in her area compared to other places?

What benefits the inquirer is to turn away from doubt and overthinking, because describing rain as strong or weak is similar to describing it as abundant or scarce, and there is no harm in that. It has no relation to the forbidden cursing of time, for cursing time involves insulting it and attributing actions to it. The people of pre-Islamic ignorance used to attribute actions to time out of their ignorance that Allah is the Creator of everything. So, when they were afflicted by hardship or misfortune, they would attribute it to time and curse it. Allah has recounted this from their saying: {And nothing destroys us except time.}