Clear sailing is often used to refer to a situation where things are going smoothly without any difficulty or obstacle. However, there are some antonyms for the phrase that give a different meaning altogether. Firstly, rough sailing refers to a difficult or challenging situation where there are many obstacles to overcome. Second, choppy waters suggest a turbulent or unstable situation where things are unpredictable and constantly changing. Thirdly, stormy weather implies that there are significant problems, conflicts, or challenges to deal with. Lastly, troubled waters refer to a situation where there is confusion, uncertainty, or unrest. In conclusion, these antonyms can help to provide a different perspective on a situation and highlight the various stages of progress that one may experience.