It's not cold enough that you need to wear a long sleeve shirt.
It's not so cold that you need long sleeves.
ーIt's not cold enough that you need to wear a long sleeve shirt.
「長袖を着るほど寒くない」
It's not cold enough ... で「十分寒くない」
to wear a long sleeve shirt で「長袖シャツを着る」
ーIt's not so cold that you need long sleeves.
「長袖が必要なほど寒くない」
it's not so cold で「そんなに寒くない」
to need long sleeves で「長袖が必要である」
ご参考まで！
カナダ 
