I like your question a lot! I think what you're trying to achieve is the best way of solving your problem. Unfortunately, although I do have a few links for you that might get you a little bit further, a perfect solution is, I fear, not available. Tides are extremely complicated and depend on many factors. Some of these are large scale effects such as the relative positions of earth, sun and moon, but others are more local, such as ocean currents or the shape of the coast. Especially the latter can make a surprisingly large difference on a relative small spatial scale. Luckily, it is possible to come a long way and have very decent approximations.
The best option, as far as I'm aware, is to use XTide, a software program that can calculate tides at thousands of locations worldwide, making use of actual measurements as well as mathematical models. This will give you by far the largest amount of information, and the most detailed information. better still, it's open source software and completely free. 229
The drawback is that it is complicated to use. Also, if you are a windows user, it is even more tricky as this is an X-windows program, developed for UNIX and UNIX-like operating systems (it should run fine on linux and macos). It is definitely possible to run it on windows, but I wouldn't recommend it for the faint of heart.
My second option would normally be to use rtide, an add-on package for the statistical program R, though in your specific case it's probably not good enough. The rtide package is fairly easy to use if you're familiar with R, and runs equally easily on all operating systems supported by R. The drawback is that it doesn't give as much detail as XTide, and it is based on data from a mere 637 stations, all of which are in the USA, so it's only of limited use for the Pacific Northwest. In addition, it takes more work to calculate certain variables such as the tidal range than to do the same calculations in XTide
A third option would be to use a website like https://www.tide-forecast.com/ where you can click your way to the relevant data. The number of stations they cover is even smaller than those offered by rtide, but they do cover the entire world. If you do not want to go the XTide way, then combining rtide with https://www.tide-forecast.com/ would probably be the best way to go: the former gives you a large number of stations in the Pacific US, while the latter will add some stations in the rest of the Pacific Northwest.
I hope this helps! 967