It can be hard to predict what swell, wind, and wave action will do in various situations. Just because the action is not coming directly into an anchorage doesn’t mean the anchorage will not be affected. Having anchored up and down the U.S. East Coast, Bahamas, and the Caribbean from the DR to Grenada we have encountered untenable anchorages that “appeared” fine when looking at the various forecasts. Swell and waves can wrap around headlands, capes, etc. with amazing efficiency. Water depth, sea floor topography, and many unknowns will have an effect. In the BVI the good news is the local old salts have the experience to give great advice for virtually every situation.

My wife studies wind, swell, and waves very carefully and has become very adept at predicting the effects on a given anchorage. I defer to her on the subject. Charterers will seldom have the experience to make the appropriate predictions except in obvious situations. Our rule when trying to do the calculus required when we can’t obtain local knowledge is to avoid any anchorage if we find ourselves in a serious discussion about “do you think it will be OK?” PredictWind, windguru, and Navily are very helpful, especially when one cannot access local knowledge.