高こう層そう雲うん

noun

altostratus clouds

A mid-level cloud type, often forming a uniform grayish or bluish sheet. Used in weather forecasts and scientific contexts.

• 明日あしたは高こう層そう雲うんが広ひろがり、午ご後ごから雨あめになるでしょう。

  Tomorrow, altostratus clouds will spread, and it will likely rain in the afternoon.