Good input and a great reference site but still confused. Reference says "Steepness = Height/Length A wave length of 70m will cause a wave to break when it exceeds 10m (1:7)" When I do the math S=H/L S=10/70
S=.14) When reversed to S=L/H you do get 7 which I assume is the 1:7 breaking point. What am I missing here? How do you guesstimate the length and more importantly, other than experience, how do you interpret bouy data or forecasts (height and period) to make the go/no go decision? I know there are many variables but am trying to get a general idea about what is considered acceptable wind waves for a 30 to 35 foot S/V doing coastal cruising.