westerly trough

例句：

1. 1. The westerly trough is responsible for the coldair that flows into the region.
   西风槽负责流入该地区的冷空气。
2. 2. Theweather forecast indicated a westerly trough developing over the area.
   天气预报显示，一个西风槽正在该区域形成。
3. 3.The westerly trough can leadto severe weather conditions such as thunderstorms and heavy rain.
   西风槽可能导致雷暴和大雨等恶劣天气条件。