If you are departing on a long ocean passage there will not be reliable forecast data available which covers the passage. This is just how it is. We are more fortunate than all previous generations of sailors, in that we have access to a wide range of tools to help plan passages. For long, and short, ocean passages, just as for all of recorded history, your experience, judgment and knowledge is important.
How would you plan for a 50 day passage, such as the sail between New Zealand and Hawaii?
Two of the routes between New Zealand and Hawaii, that you will discover from reading cruising guides are roughly shown:
The two routes are, very approximately:
Its useful to remember that there are two types of decisions:
In developing a strategy for this particular passage, one of the two general routes above can be chosen. Once you have decided on the general shape of the passage, the remaining decisions are:
These are discussed in more detail soon.