可以，如果是写诗这样写很有意境，如果是口语，你可以说夏天的雨很凉爽。

完全可以，但是偏向于书面语言，口语交流不会这样文艺化，口语上要么夏雨，要么冷雨，或者夏天的雨真凉。 absolutely yes, but it's more like writing language rather than oral language. when you are talking with someone ,you may say" summer rain/ cold rain/ the summer rain is so cold." But ," cool summer rain"sounds like a sentence of a poem,it's really a poetic words

Hi Beth, you can write like that, but if you say like that, it seems strange. :-P

可以，不过是个phrase, 不是完整的sentence. 比如，凉爽的夏雨让我烦躁的心情突然好了起来。 这个有点文学化，但口语里可以用，不过不能单独使用，因为句子成分不全。

you can say 夏天凉爽的雨