曇くもりがち

na-adjective, noun which may take the genitive case particle 'no', noun

mainly cloudy; tending to be cloudy

Describes weather that is often or mostly cloudy, or a period when cloudy conditions predominate. Often used in weather forecasts.

• 明日あしたは曇くもりがちの天てん気きでしょう。

  Tomorrow will be mainly cloudy.

• 今こん週しゅうは曇くもりがちで、なかなか晴はれません。

  This week has been tending to be cloudy, and it hasn't cleared up much.