风云变幻 (風雲變幻) fēng yún biàn huàn

fēng yún biàn huàn set phrase the weather may change unpredictably; a changeable situation
Domain: Idiom 成语
Notes: (CC-CEDICT '風雲變幻'; CCI '风云变幻', p. 78; Guoyu '風雲變幻')