Why is it foggy over the North Pacific warm current in winter?

In addition to the upstairs saying that water evaporates into steam (in fact, water evaporates everywhere, steam is gas, invisible, and fog is liquid), more importantly, the second half of the sentence, when warm steam rises, it meets a cold airflow over the North Pacific Ocean (this. . . Complex formation), liquefied into small droplets, forming fog.

I think so, too. I haven't taken geography class for a long time.