Certain harbors are gathering places for sailors headed offshore. Back in the good old days I met a lot of fellow cruisers while arguing about the weather as we holed up waiting for a weather window to jump offshore. The sources of information were few — pretty much everyone shared the same data. Here in the USA the main sources were NOAA Coastal, Offshore, and High Seas text forecasts, gathered by weather fax, VHF and SSB radio. Sometimes we downloaded small-scale (large area) weather maps that gave us very general information on huge areas of ocean. And sometimes we just walked up to the weather station, as in Bermuda.
Offshore, many of us didn’t get further updates, except possibly some scratchy voice forecasts via SSB radio. We usually sailed with three or four days of good predicted weather, after which we took what we got. Forget trying to predict the weather in segments smaller than 100 miles. Ocean current predictions were just general averages.
There were a lot of little things we did to supplement forecasts. We would wait in harbor until the wind clocked around after a front. A thermometer would tell when we had reached the Gulf Stream. A change in swell patterns might tell of an approaching storm. A certain ocean color and a type of seaweed indicated you were in the Gulf Stream. Or, you could spot the stream miles off by the line of clouds and thunderstorms down the middle.
Sounds pretty primitive, but all of these seat-of-the-pants methods, in conjunction with historical weather and route information summarized on the pilot charts, worked quite well. Still, I would argue that choosing the right route in the right season remains the single best weather decision you can make.
Taking into consideration not only the wind, but the currents, the speed of your boat, your planned times of departure and arrival, can be confusing. Wouldn’t it be nice to read a general forecast for a large ocean segment, hundreds of miles on a side, and a weather map with winds and currents for that patch? What if you could take into account other variables and automatically get a plan for best departure and arrival times, along with the route to take for the most comfortable passage?
There’s an app for that
The digital revolution has brought us an era where we not only have 10 to 14 days of coastal weather predictions served to us via the internet. Many voyagers continue to enjoy these benefits when offshore by utilizing weather apps, satellite internet connections, and high-resolution displays, from phones, laptops, dedicated chart plotters and large monitors. Resolution is such that you can download predictions for your patch of ocean, including ocean currents. The addition of near-real time ocean current information is a huge leap forward, and makes for a much speedier and more comfortable trip.
To read the rest of this article check out Ocean Navigator!