https://weatherspark.com/y/298/Average-Weather-in-Prince-Rup...
Calling it British Columbia certainly tracks then!
One reason I can think of is availability of labor, but how many people does it take to run a good-sized port? Not saying we build a new port out in the middle of nowhere, but a location where there is already a small- to mid-sized town nearby might be suitable. And also consider that the existing port locations have housing costs that are probably too high for many/most port workers anyway.
It seems like we need more ports in the US in places similar to Prince Rupert.
> The fourteenth of August (in the year 1834) was the day fixed upon for the sailing of the brig Pilgrim, on her voyage from Boston, round Cape Horn, to the Western coast of North America.
> What brought us into such a place, we could not conceive. No sooner had we come to anchor, than the slip-rope, and the other preparations for southeasters, were got ready; and there was reason enough for it, for we lay exposed to every wind that could blow, except the northerly winds, and they came over a flat country with a rake of more than a league of water.
> I also learned, to my surprise, that the desolate-looking place we were in furnished more hides than any port on the coast. It was the only port for a distance of eighty miles, and about thirty miles in the interior was a fine plane country, filled with herds of cattle, in the centre of which was the Pueblo de los Angeles,– the largest town in California,– and several of the wealthiest missions; to all of which San Pedro was the seaport.
The port itself is protected by geography, and is one of the deepest natural harbours in the world.
It's a neat place!
Well, except for being one of the rainiest cities in Canada.
Edit: If you're interested in this kind of thing, here's a drone video I shot last year, of Prince Rupert's container port: https://www.youtube.com/watch?v=9DyG9wOWi0c