阴晴不定 yīn qíng bù dìng

DEFINITIONS

  1. erratic weather; describes weather that fluctuates unpredictably between sunny and overcast conditions

CHARACTERS

阴 yīn 'female' principle; dark; secret
晴 qíng clear weather, fine weather
不 bù no, not; un-; negative prefix
定 dìng decide, settle, fix