After extensive and painstaking research involving repeated instances watching our fleet walk away from us by taking advantage of the vagaries of Puget Sound tidal currents, we decided that these currents are perhaps indeed worth paying attention to.
One could of course go down to the local chandlery and buy a copy of an established and well-vetted current atlas that would be both inexpensive and easily used onboard. That however has the disadvantage of requiring leaving the office desk and being entirely too practical.
Instead, we'll turn to the MoSSEA (Modeling the Salish Sea) research work being done at the University of Washington. This hindcasting effort uses the Regional Ocean Modeling System (ROMS) with atmospheric, river, and tidal forcing to create high resolution models of the Puget Sound circulation system.
I am currently making a general pest of myself bugging busy people to give me true current velocity outputs, and if I get these I will probably keep them to myself in search of the aforementioned 'unfair competitive advantage.' However, here are some publicly available toys to take a look at:
While I couldn't find any explicit surface current output available from the MoSSea project, I did find this nice animation of surface salinity over a spring-neap tidal cycle. Mixing significantly complicates the use of salinity as a tracer of currents, but it is still interesting to watch this animation for some of the complex eddies and other features relevant to sailing. Click here for animation.
The other fun toy worth looking at is flowWeaver, a visualization tool built on the same MoSSea model as the animation. This will most likely be available at some point as a web app, but in the meantime you can download it and run it on your local machine. Mousing over the map reveals the deep and surface paths that a water parcel at your chosen location would take over a two week period. Clicking on the map releases a 'particle' for you to track, and clicking and dragging animates a section of the map. Click here for flowWeaver.
