The Washington State Department of Transportation has come up with a really cool tool with the unfortunate name of Terminal Conditions. Now you can go online and find out how many spaces are available for the next sailing! It updates every 15 seconds, so it’s virtually real time.
Here’s the link for the Winslow terminal:
And here’s the one for Coleman Dock on the Seattle side:
I’ve got them both bookmarked on my iPhone home screen.