Learn Hardcore Latin: Tempestas tandem transiit, et nautae e portu discedere possunt. - The storm has finally passed, and the sailors can leave the harbor.

Breakdown of Tempestas tandem transiit, et nautae e portu discedere possunt.

Why is tempestas in that form?

Tempestas is nominative singular, because it is the subject of transiit.

So tempestas transiit means the storm passed or the storm has passed.

This noun is from the 3rd declension:

What does tandem mean, and where does it go in the sentence?

Tandem is an adverb meaning finally, at last, or eventually.

In Latin, adverbs often have fairly flexible placement. Here it is placed between tempestas and transiit:

This gives the sense The storm finally passed or At last the storm passed.

Its position helps emphasize the idea of relief or delay.

Why is it transiit instead of transit?

Because transiit is perfect tense, while transit would be .