The winter came and it's getting colder.
冬がきて寒くなった。
英語では、『冬が寒い(the winter is cold)』とはいいません。
気温をあらわす場合、主語は『it』です。
It is hot in summer.
（夏は暑い）
It gets warmer in April.
（四月には暖かくなってきます）
お役に立てたらうれしいです。
＜ボキャブラリー＞
winter = 冬
cold = 寒い
getting colder = 寒くなってきた
"When winter hits the temperatures got cold."
or
"The temperatures are getting colder as we enter winter."
"Hit" when something happens quickly or takes effect. The date on the calendar may say winter, but until the cold weather comes it may not feel like winter.
"Temperature" cold or hot feeling around us.
"The temperature has been cold today."
"The temperature was higher than normal today."
"enter" to go into something, a place, season, etc.
【例】
"When winter hits the temperatures got cold."
（冬が来て寒くなった）
"The temperatures are getting colder as we enter winter."
（冬に入る寒くなってきた）
"Hit"とは何かが急に起こったり、影響したりすることを言います。
暦上では冬かも知れないけど、寒い天気が車で冬が来た気がしませんよね。
"Temperature" （気温）私たちの周りの寒かったり暑かったりする温度の事です。
【例】
"The temperature has been cold today."
（今日の気温は寒いです）
"The temperature was higher than normal today."
（今日の気温はいつもより高いです）
"enter"（入る）とは季節や場所に入る、進入するという意味になります。
When you want to explain that it's now becoming colder because winter has come, then you can say:
-Winter is here, and it's getting colder
-It's getting colder now that winter has come
-Winter has come and it's getting colder.
冬が来て寒くなってきたことを表す言い方です：
-Winter is here, and it's getting colder
冬が来て、寒くなってきた。
-It's getting colder now that winter has come
冬が来たから寒くなってきた。
-Winter has come and it's getting colder.
冬が来て、寒くなってきた。
In the effort to express how cold it may get in one's city in winter you may use adverbs like exceptionally, extraordinarily, surprisingly or even exceedingly. This expresses a great degree and emphasizes how cold it may get. You may also simply say the temperatures drop very low. This has the same effect.
冬の寒さを表すときは、exceptionally（非常に）, extraordinarily（異常に）, surprisingly（驚くほど）、 exceedingly（とても）などが使えます。寒さを強調する副詞です。
また、シンプルに「気温がすごく下がった（the temperatures drop very low）」ということもできます。
If something is 'setting in' it means that it is becoming more established and improving its position.
A 'chill' is a cold wind or cold atmosphere.
Eg. "There's a real chill to the air this evening."
「___ is setting in」は「___がより本格的になってきた」といった意味です。
「chill」は「冷たい風」または「冷たい空気」のことです。
【例】
"There's a real chill to the air this evening."
(今晩は本当に空気が冷たい)
I can tell winter has come because it's getting colder.
It's chilly out, that means winter is here!
The two sentences you see above are great ways to express that winter is here because it is cold outside. In the second sentence you will see the word chilly, which means cold. We use the word chilly to describe when the weather is cold. This is a word that is common in our everyday conversation, especially when describing the weather, and would be a great addition to your vocabulary!
It's getting colder and colder because of the winter season.
Both of these examples are good ways of simply saying because of winter the weather is becoming colder. You could even go further by talking about temperature and winter weather. "It has become colder and colder because of the many winter storms we've had."
これらのどちらの表現も、冬が来たので寒くなったという事を簡単に説明するいい表現です。
冬の気温や天気について話して、もう少し深く話事も出来ます。
【例】
"It has become colder and colder because of the many winter storms we've had."
（冬の嵐が沢山来たので、ますます寒くなってきました）
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