I can still tolerate the heat because the humidity is not that high yet.
Even though the temperatures have been high in May, I've been able to handle the heat because the humidity hasn't been too bad.
この場合、次のような言い方ができますよ。
ーI can still tolerate the heat because the humidity is not that high yet.
「まだ湿度がそんなに高くないので、暑さに耐えられる」
can tolerate「耐えられる」
humidity「湿度」
ーEven though the temperatures have been high in May, I've been able to handle the heat because the humidity hasn't been too bad.
「５月はずっと気温が高い日が続いているが、湿度がまだそこまで酷くないので耐えられている」
to handle the heat で「暑さに耐える」
ご参考まで！
カナダ 
