What is the proper way to describe the weather as cool?

Question

I was asked 今日{きょう}天気{てんき}はどうですか?

My response was: 涼{すず}しいです。

I was told that's not the right way to say that. Instead I should say: あまり寒{さむ}くなりません。

Which is the right way? If I'm wrong, why? And when should I use 涼{すず}しい?

Answer 1

This is such a tricky question; It almost caught me.

The other person would be correct if:

1) S/He said 「あまり寒{さむ}くありません。」 and not 「あまり寒くなりません。」. While the latter is not totally impossible, the former would be way more natural.

AND

2) The conversation took place in the winter. ← très important!

「涼{すず}しいです。」 ("It's cool") is generally said only during the summer (or the warmer half of the year) when it happens to be nice and cool on particular days. It is a welcome change from what one would normally expect during that time of year, which would be 'hot and muggy'.

It would be unusual, if not terribly incorrect, to say 「（今日は）涼しいです。」 in the winter. It would indeed sound considerably more natural to say 「（今日は）あまり寒くありません。」.

Likewise, native speakers would not say 「今日は暖{あたた}かいです。」 in the summer when it is a little less hot than usual. It is a welcome temperature change for a short period of time, but we would say 「今日はあまり暑{あつ}くない。」.

In conclusion,

「涼しい」 describes a higher-to-lower temperature change.

「暖かい」 describes a lower-to-higher temperature change.