雲くも行ゆきが怪あやしい

expression, i-adjective

the clouds look menacing; threatening weather

Literal meaning: the sky looks threatening, suggesting bad weather is coming.

• 雲くも行ゆきが怪あやしいから、傘かさを持もって行いったほうがいいよ。

  The clouds look menacing, so you'd better take an umbrella.

expression, i-adjective

things don't look good; the situation looks ominous

Idiomatic extension: the outlook for a situation is uncertain or threatening, not necessarily weather-related.

• 交こう渉しょうは雲くも行ゆきが怪あやしくなってきた。

  The negotiations are starting to look ominous.