To add an exclusion boundary for Weather Routing:
Login to https://forecast.predictwind.com with your account details.
Click on Weather Routing and select Sail Routing or Power Routing
Click on Routing Options.
Select Boundaries.
Click Create Boundary.
Click on the map to set your desired boundaries.
Add all exclusion points and return to the first marker to close the shape.
Click on the X to finish setting your boundary area.
Calculate your route.
The routing provided will exclude the area of the boundary.