There are no clouds in the sky.

万里无云。

《新英汉大辞典》

Which was odd, because although there was a bright full moon, there were no clouds in the sky to break up the moonbeams and make them dance so.

这有些古怪，因为尽管月亮很圆很亮，天上却没有能够让月光舞动的云。

youdao

The pink to white region above the clouds appears to be the stratosphere; this atmospheric layer generally has little or no clouds and extends up to approximately 50 km above the Earth’s surface.

云层上粉色到白色的部分是平流层所在的位置，这个层次中通常很少有云，大约延伸到离地球表面50千米的空中。

youdao

Yet it would be a mistake to say there are no clouds on the horizon.

ECONOMIST: Orange County

The day we had planned it for was an absolutely fantastic spring morning with no clouds, it just went off perfectly.

BBC: February: Touched by an angel

If you posted on Twitter, "I'm going on vacation to San Diego, hope no clouds because want to catch some waves, " your tweet would be considered suspicious because you used three words on the watch list.

CNN: The government is reading your tweets