Weather Wizardry


Sailing season is the time to be aware, and the place to start is  (published May 2009)

We’ve all seen the headlines and read the stories. Each year, someone is caught unaware by an approaching squall, knocked down in a gale or storm, and hurt—or worse. Last year it happened during the Chicago to Mackinac Race. And earlier this year, there were several instances on deliveries between New England and the Caribbean. Sometimes the crews were experienced; others, they were relative novices. Often, we don’t even hear about the accidents. And usually, the problems are related to weather.

Several decades ago, while on a singlehanded speed record attempt from England to Newport, RI, I found myself in some of the worst weather I’d ever experienced and on the wrong side of every wind shift. I decided to do something about it by learning more about how weather worked and using that knowledge to improve my own circumstances. Once I possessed that information, I felt that it was my duty to help other sailors understand the weather. If I could save one life by sharing my knowledge, how could I responsibly refrain?

Putting weather information “out there” in a way that’s detailed, quickly understandable, and useful in helping us avoid problems or increase our competiveness has become a decades-long effort. My partner in presenting this information, Lou Roberts, has spent his life developing tools that help people learn, and has been employed by numerous Fortune 50 companies to create online training programs for their own employees. Our combined efforts have produced the Weather Routing Wizard, a free online tool dedicated to helping you learn about weather, get the information you need, and understand how to effectively apply it. In a world of almost-too-much information, we have tried to boil the content down and put understandable, useful info at your fingertips.

Whether I’m teaching a weather seminar, presenting weather information in a magazine article or book, or simply pondering the weather myself, I break the information down into relevant, bite-sized building blocks. I look at the basic elements of what’s taking place and try to expand on that perspective to build a mental image of what’s really happening around me and how things are changing. I look at the basics, determine how they work and move forward from there. Hot air rises and cold air sinks everywhere in the world—Atlantic or Pacific, north or south. Once we have achieved a global perspective on how those similarities and variations work, we will achieve global value. We can take that information anywhere and get a better understanding of weather, which we can then apply to our own unique situation.

Understanding the weather takes time and effort. Of course, that effort may someday save your life or the lives of those you love, so it seems to me that a little time and effort may be a worthwhile expenditure, especially when the information is readily available.

When preparing for a sailing project, I’ll sometimes spend months doing research. Other times, I’ll only spend 15 minutes or an hour. To a large degree, it depends on the type of sailing project with which I’m involved. Am I going for an afternoon sail on Long Island Sound? Are we taking off for the Caribbean? Or are we taking a trip up the Indian Ocean from South Africa? They all require different types of preparation and different types of information. The Weather Routing Wizard takes you step-by-step through the entire process.

If you were planning a long passage and heading to areas largely unknown to you, you might want to do a climatology study, discovering the range of temperatures, frequencies of high winds, wind directions and so forth. If you were going for an afternoon sail, you might just want to see what the weather maps told you. Perhaps you’d like to know about the possible squalls that the satellite imagery implied might be coming toward you. Or you might want to know that the radar showed rain over the horizon and the rate at which it was approaching.
Regardless of what you’re planning to do, it’s better to do your planning before you’re too deeply immersed in the problem. Allow yourself time to actually do something about it. If you’re leaving Bermuda in early May, heading north to New England, you might want to know that the water temperature north of the Gulf Stream can be 45 to 55 degrees Fahrenheit while you’ve still got time to get warm clothes for the trip. If you’re going to do the Transpac Race in early July and it’s January, the long range climatological patterns may imply a year in which winds might be stronger than usual. Perhaps your limited resources for the race might be well applied toward a bigger bulb on the keel or a stronger spinnaker rather than investing in a newer drifter. Well-run sailing campaigns have done exactly that, and have been well-served by the long range planning.

Through the Weather Routing Wizard, available on the homepage of or directly at, you can find a wide array of tools to help you better understand how to find, interpret and use weather information. Would you like to know the current weather situation surrounding your area? Under the dropdown menu, “Tools > All” then “Air Nav Tool” will help you understand how to access virtually every airport in the country, get their direct dial telephone number for the real time weather, and link to the site.

Would you like to learn how to better interpret satellite imagery? Scroll further down the list of “All Tools” and you’ll find “How to Read a Satellite Image.” Or perhaps you’d like to find out how a sea breeze really works in three dimensions. Go to the “Sea Breeze” tool and you’ll find an illustrated discussion of that topic. You’ll also find lists of weather map symbols and acronyms, along with an easy way to understand the implications of the clouds overhead and how they relate to the larger scale weather pattern.

Of course those are just a few of the tools that can help you better understand how weather works. There is also a list of weather information sources. Here you’ll find links to maps, radar, buoy data, currents, tides and text forecasts, and how to compare and contrast them to get a more comprehensive understanding of the weather that will be surrounding you. These listings will prepare you to deal with nearly any situation you’re going to encounter.

Once you understand how to interpret weather information and where to acquire that information, we offer suggestions on how you might want to apply the information to your own situation. If it’s blowing 35 knots, a racing crew will make different choices than a cruising couple—and they’re both right. A heavy displacement Swan monohull will often take a very different route than a 110-foot racing catamaran. The boat speeds are significantly different and the way those two vessels perform within a particular seaway is often different, so the effect of a given distance in a particular situation will also be substantially different. Different assets and liabilities or vessel performance characteristics will often require different decisions.
Sun Tsu’s The Art of War suggests that by knowing yourself, your adversary, the surrounding terrain and the weather, you will provide yourself with victory. It’s my belief that by understanding our assets and liabilities, we will provide ourselves with some terrific sailing.

Bill Biewenga is a navigator, delivery skipper and weather router. His websites are and He can be contacted at

Author: Bill Biewenga