the weather is not too good
The Chinese idiom, Pinyin is ti ā Nb ù Zu ò m ě I, which means that the sky is not perfect. It means that the things to be done are affected by the wind and rain. From Yun Zhai trivial talks (4).
The origin of Idioms
Sun Li's Yun Zhai trivial talks (4): "the sky is not beautiful, suddenly snowflakes come."
Idiom usage
It is often used in oral English. I don't want to have a bad day. It's almost dawn and it's raining. Wei Wei's Fire Phoenix
Analysis of Idioms
Heaven is not beautiful, and heaven is not beautiful
the weather is not too good
the difference between heaven and earth - xiāo rǎng zhī bié
ready to die the cruelest death for principles - gān xīn tú dì