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It was early May, and we were bound for New York, a familiar 1,500-mile passage with Bermuda looming as an optional waypoint. Over the years we have encountered a few serious gales, although they've invariably been on the boisterous passage south, which we've always made in early November. Sure, we had a few wild, roller-coaster days, but I never felt the boat or crew was in danger. Yet these gales took their toll on George mentally. He had come to dread the offshore passage and it became an unfortunate by-product of wanting his boat in both locations. This time however, he was armed with a new weapon to help us avoid possible gales: an expensive, detailed weather forecast obtained from a well-respected weather-routing service.
George proudly unveiled the forecast in the cockpit as we prepared to shove off. In what struck me as a near comical leap of faith, he announced that we had to be away from the dock by noon to be "synchronized" with the forecast. George had provided our general route and the routing service responded by faxing, at the last possible moment, an impressive mound of paperwork, after a final satellite update. The forecast divided the passage into six-hour segments and was stunningly detailed. From typical wind and sea-state predictions, to likely cloud patterns and recommended course changes, the forecast took all the guesswork out of the atmosphere. Or did it?
 Setting your course based on the latest forecast is a common procedure, yet long-range offshore forecasts are a risky gambit for cruising sailors. | |
Almost immediately, the forecast became the main topic of conversation, and not for its uncanny accuracy. Right out of the chute we had light and variable winds, predominantly from the south. Six hours out of St. Thomas a 10-knot south wind emerged. After 24 hours the wind lodged in the SW and there it would remain. While the forecast was calling for 15-knot easterlies, we were romping along before a hot 25-knot SW breeze. George was amazed, "how could they get it wrong right from the start." Interestingly, the long range SSB forecast out of Norfolk was for the most part accurate. We began teasing George that he could have made better use of his rather sizable investment by consulting an astrologer.
I have great respect and sympathy for weather forecasters. They have a thankless job and are only remembered when they are wrong. However, these long-range offshore forecasts are a risky gambit for cruising sailors. They just can't be interpreted in six-hour segments, at least not for offshore work, as there are too many variables. The average sailboat doesn't move fast enough to alter the basic premise that, even in a large general weather system, the weather around your boat is essentially local. These forecasts are risky because they set you up for disappointment, and any surprise in the forecast is somehow seen as a failure. The single biggest reason most people are put off by offshore sailing is that they begin a passage with preconceived notions of how it is supposed to be 'out there.' Neptune has a sardonic sense of humor and loves to upend these notions. Long-range weather predictions and routing services just reinforce these preconceived notions because they are taken at face value. It's not the forecasters fault, it is the way the information they provide is perceived. We are so hungry for information these days and it is easy to assume that any information is accurate.
 Assuming that all information available is correct can put you in a dicey situation. | |
We arrived on Sunday, and Monday morning George called the routing service. He wanted to let them know that he was disappointed and he also wanted a new forecast for the duration of the voyage to New York. Our plan was to be away later that afternoon and I hoped to be back in Florida by the weekend. George returned to the boat with a concerned look on his face. It seemed the routing service was suggesting that we stay put in Bermuda for the next four days. "Why?" I asked. "The Bermuda Weather Service is forecasting good going all the way to the coast." "Well," George began, "a front that looks like it is going to stay north will actually shift south and create 25-knot NE winds right when we should be crossing the Gulf Stream three days from now. They are calling for 12 to 18-foot seas in the Stream."
I was incredulous. We had just spent a week verbally abusing this forecasting service, now we were going to delay our departure four days based on the possibility of a front dipping south? I convinced George to accompany me to the US Naval Air Station Weather Office and we had a long chat with the chief meteorologist. He thought it was unlikely that the front would drift south. In fact, he thought we had a nice weather window to make the 700-mile passage. "The winds should stay SW and then go west, so you may be able to get your westing in early. Even if the front comes down a bit, you'll be well below it. I don't see the Gulf Stream causing you much trouble."
George wouldn't budge. He had suddenly renewed his faith in the routing service. He insisted that we delay our departure until Thursday. I blew up. I was, after all, the Captain. Although I realized I was probably overreacting, I told George that we were leaving as planned and that if he didn't like it, he could fire me—the choice was his. He wavered and I held my ground. Angrily, he relented and we set off. The next four and half days were terrible. The weather was perfect, the forecaster at the Naval Station had been accurate, but an icy chill settled over the boat. George and I spoke only as necessary. Nearing the Gulf Stream, I hoped for a NE gale just so I could concede that George had been right and we could try to mend our rift. Aside from a low undulating swell, there was little evidence that Stream existed, and we glided along, close reaching before a moderate westerly.
We cleared Sandy Hook and secured the boat. George gave me a lift to the airport. We didn't speak in the car. At the gate George paid me, we shook hands and parted ways, two stubborn men watching a friendship dissolve. Sitting on the plane I realized I had made a stupid mistake. In the end, the forecast was of no significance. What did matter was that I failed to accommodate my friend's feelings.
Thoughts on Long-Range Weather Forecasting I have replayed the incident that occurred on George's boat many times in my mind, trying to analyze why I reacted so strongly to the decision to delay our departure. It boils down to experience and philosophy. The simple truth is that long-range weather forecasts, even the best that you can buy, are rarely accurate. Secondly, and more importantly, a basic tenet of offshore sailing is that you must strive to be self-sufficient. Obtaining the best weather information is a vital part of the equation when preparing for a passage, but it is just that, a part of the equation. As a skipper you must be prepared to deal with changing conditions, it is much less prudent to depart with an uncertain forecast than to depart and be locked into a weather forecast that might not pan out. General route planning, which always takes weather into consideration, is more important than obtaining long-range forecasts. I consult pilot charts before every passage over 500 miles. These charts contain a wealth of information about currents, prevailing winds, likely sea states, temperature ranges, etc. Pilot charts can be wildly inaccurate in the short-range, but in the long- range, they are highly dependable. Like all forecasts, you play the averages. I also obtain the best possible local and yes, even long range forecasts before I depart. Tropical storm considerations are another matter completely, but these storms are so well publicized it is difficult for one to sneak up on you. Of course, we all know, as was the case with Hurricane Lenny, even the best forecasts can be deadly inaccurate. It must be stated that weather fax, SSB, and satellite communications dramatically improve the usefulness of all forecasts. Indeed, these forecasts can be updated regularly and received aboard so they are no longer "long-range forecasts," but more-accurate, short-range predictions. If current weather information is vital to you when offshore, I recommend investing in a top-quality fax receiver and taking the time to learn how to interpret the information and weather charts yourself. |
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