How to say “The ground is soaked; it must have rained overnight.” in Japanese

In Japanese

地面(じめん)がびしょびしょなので、夜中(よなか)に雨(あめ)が降(ふ)ったに違(ちが)いありません。

Jimen ga bishobisho na node, yonaka ni ame ga futta ni chigai arimasen.