The easy answer is to wait it out, but simply going around Cypress Island works well, too.
This is a view down Guemes Channel across four mile wide Rosario Strait at what would be Thatcher Pass if you could see it.
That wall of white is creeping up the tip of Cypress Island.
You can navigate through the soup and wonder about ferries or turn like that cruiser did, and run around
behind Cypress Island to cross Rosario Strait over to Peavine or Obstruction Passes.
The detour adds only a little bit of time and three miles extra travel, but misses today's fog bank. This is a common situation. Further south at Lopez or Cattle Pass, or Deception Pass, it will likely be the same.
Here is a link to a foggy article that may enlighten some > Dealing with fog in the San Juans
