When an argument blows over, it becomes gradually less important until it ends and is forgotten.

I thought that after a few days the argument would blow over. 我觉得过几天这场争论就会逐渐平息。

When a storm blows over, it becomes gradually less strong until it ends.

The storm raged all night but by morning it had blown over. 暴风雨肆虐了一整夜，但到第二天早上就平息了。