I dunno what the offshore buoys are primary used for, but they are quite a ways out there. There is a string of 6 or 7 of them running up/down the west coast. I think most of them are operated by NOAA. I looked up one of them, and it is anchored in 4000 meters of water... way off the continental shelf. Environment Canada has some buoys out there too, but I can't seem to find them in Windy for some reason. There are some inshore buoys as well, but you have to zoom in to see them. Here's a screenshot of the string of offshore buoys in Windy:
Tim