To clarify, I used the average height multiplier for the 10% and 1% numbers (1.27 and 1.67, respectively), and while admittedly conservative, I feel they do provide a reasonable reference point for making prudent decisions.
That's fine, so long as you understand the implication of the numbers - eg that they are in fact NOT the heights of the 1 in 10 and 1 in 100 waves, but of the average of waves bigger than the 10% and 1% waves . . . just for your reference the 1.27 multiplier matches the height of about the 4% wave and the 1.67 is about the .4% wave.
Besides, I would be surprised if the depth of water shown on the charts is close to within 4' in some places,
That's interesting. I would have expected the charted depths on the course to be within 1' accurate (of course taking into account the chart depth datum). Out of curiosity, do (or anyone else here) you have any specific observations suggesting 4' errors along that course (or elsewhere in the SF racing area)?
Another discussion is whether you should have a cockpit display showing the depth, or just rely on the plotter/charted depths.
Moreover, I wouldn't care to be that precise in selecting a reference point anyway, since I will continue to do exactly what you suggest and 'feel the waves' before choosing how close I'll get.
Excellent. The trick here is to realize that as you come from the east bar to the west bar (or the other way) and are looking in at the shallow water (eg 'VFR navigation') you may well not see a .4% wave happen, so you may not see the potential 'breaking wave zone' with an actual breaking wave. The implication is that you need to be more sensitive to looking at wave shape and size to judge (and not just looking for breaking) where the potential breaking wave zone in fact is.
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