We weren’t expecting what was waiting for us. The warmth of the sunrise, a slowly building northerly breeze, and some of the strongest coffee on the planet encouraged us to work the foredeck a bit and get code zero flying. The big headsail was drawing beautifully, the familiar drone of engine finally became pleasantly silent, the digital speed readouts were stuck on 9 knots, and the miles were ticking off just as easy as you please. This was exactly how the professional weather routing service that developed our personalized weather forecast for the passage said our weather window would look―ideal in real time just as it was on paper. But things were about to change for the worse.
We were rocking along the rhumb line aboard Cuyler Morris’s Morris 45 Firefly from Northeast Harbor, Maine, to Bermuda, and eventually on to Antigua. The long-range forecast the weather routers Cuyler used to determine our weather window called for northerlies from 9 to 16 knots all the way from Maine to the southern side of the Gulf Steam. There are countless stories of cruising boats getting pasted by northerlies in the Stream, but the light winds we saw were hardly enough to ruffle it. We’d been pleasantly motorsailing along for 2 and 1/2 days. Up to that point, the toughest challenges we’d faced were the bitter cold north of the Stream, minimizing our exposure to adverse current in the Stream thanks to the Gulf Stream analysis provided in our forecast. With the code zero set, and a dated long-range forecast in the back of our minds, we’d wishfully imagined averaging 9-knots power reaching the last 250 miles into St. Georges. Cue rude awakening.
Weather window slams shut
The wind didn’t increase immediately. It was more like a pot that slowly came to a rolling boil. Over the course of the afternoon, true wind speeds inched into the high teens (high 20s apparent). We doused the code zero in favor of the full main and jib. As afternoon turned to evening, true winds in the high 20s wound forward off the beam and had us tucking a reef in the main and rolling up some jib. All hands tucked another reef and rolled up more jib before the midnight watch when winds hit the high 30s—true. Need I say the ride had become decidedly less placid than it had been?
A distant low developing near the coast of Georgia was compressing the edge of the high we’d been sailing through and cranking up the wind. As the night wore on we were bashing into solid 40-knot headwinds with the gusts hitting 50. We’d fallen off the rhumb to minimize the thrashing (and losing VMG in the process), but still managed to land off a couple of waves jarringly, wake-up-the-off-watch, hard. Now we were forcing down water in a conscious effort to keep hydrated, and protein drinks to help keep calories in our stomachs. Green waves periodically broke on the pilothouse windows. The boat heeled 35 degrees with hardly any sail up. Now just bracing yourself in the galley had turned into the most evil ab workout ever devised, everything from going to the bathroom to moving around was an ordeal, and working on deck was an exhausting adrenaline rush that most cruisers would rather avoid. The boat was up to the conditions and thankfully so was the autopilot, and we were just wet, cranky, fighting against seasickness, and losing sleep (not unheard of on an offshore passage). But how did it happen? How did the long-range forecast differ so much from the weather we actually encountered?
Anatomy of a weather window
Professional weather routing services don’t create weather windows; they identify favorable weather patterns and routes (avoiding storms, headwinds, adverse currents) that fit predetermined parameters of each individual boat they work with. Obviously a potential record-breaking attempt will have a different set of parameters than a boat looking for an easy delivery, but in the end, when a forecast for the next 72 hours ahead calls for “winds N-NE from 6-16 knots” that means: According to all the available data and analysis, the probability is very high that the winds will be N-NE from 6-16 knots. BUT due to the inherent volatility of the weather patterns (especially offshore and around the Gulf Stream as we learned firsthand), this is subject to change.
No matter how sophisticated the weather prediction system, the possibility for a weather forecast to be “wrong” is directly related to how old the forecast is and how many hours (or days in the future) it’s attempting to predict. Any forecast, but particularly those predicting more than 72 hours in advance, are subject to (sometimes dramatic) change and must be constantly updated as time passes. That means any weather window (or forecast for that matter) can only really predict 72 hours in advance with any degree of certainty. Weather routers make long-range predictions and use that information to help determine the weather a cruiser will experience on passages longer than three days, and can help boats dodge potential bad weather with updated forecasts once they’ve left port, as long as there’s an open line of communication.
In our case, we made a simple mistake that any boat could make. We saw a rosy long-range forecast and took it for gospel. Having the forecast for the first 2 and 1/2 days be right on the money only fortified our wishful thinking. We monitored onboard weather software and received weather forecasts and tuned into Herb (Southbound II) Heidelberg on the SSB. The weather maps did not indicate we were in the midst of a telltale low storm center, but rather that we were wedged in between high pressure (highs mean light winds, right?) and a low that was passing well to the north and west of us. As a result we ended up in the area where winds intensify as the two systems squeezed into each other for two days. And we didn’t do what the weather routers encourage (and frankly what separates their services from simply receiving NOAA weather reports)―we didn’t keep in close contact with them (via email or sat phone) once we left Maine.
However, even if we had learned the severity of the weather we were going to encounter a little sooner, the only thing we may have done differently was to possibly make a bit more easting (but not too much) to help with our angle as the wind clocked around to the SE. In fact, some boats that sailed more than 60 miles east of the rhum got clobbered, and sailed many more miles (and hours) through the blow for their effort. We’d made great progress prior to the blow and crossed the Stream easily. We were closer to our destination than any other land. Like they say in the Mafia, “We were in too deep to get out.”
As the weather deteriorated, we knew we could handle it, albeit a bit uncomfortably. But as the wind came directly from the SE―smack dab on the nose—a little frustration set in. It was about 0200 during our second night in 40-knot winds when we were forced to fall off to the point that we were sailing a course that was almost parallel to our destination. VMG was down to about 1 knot, and Boonie, who is a very experienced offshore racer, had had enough. He dialed up the sat phone and after several lost connections, and over the noise of the wind in the companionway, was able to talk to one of the weather routers who provided a crucial bit of info. He told us that the wind strength was going to continue all the way into St. Georges, but that we could also expect a 30-degree favorable shift. This is a key benefit of using a weather router once a window shuts down. He gave us just the little morale boost we needed with up-to-the-minute meteorological data and would have recommended an informed course change if necessary. I spent the rest of that watch watching for the big header and appreciated the fact that he was able to tell us it was coming. He was right. It came, we tacked, and finally were back on a course that would bring us around into the calm water of the harbor. It was only a matter of hours (not days) now.
The wind never relented. It blew hard on the nose and made us work even as we turned the corner around the reef and saw the pink houses of Bermuda under angry gray skies mere miles in the distance. It was only after we’d cleared customs and tied up along St. Georges’ famous wall did we learn that many other boats were cursing the weather just like us. In fact, there were four rescue missions (two boats sank) around Bermuda during the time we were out there.
Weather windows can only be rough guides. Part of the romance and adventure of cruising lies in the fact that we still sail off soundings, over the horizon, and into the unknown just like the British that first washed ashore in Bermuda. Of course technology has advanced to minimize the unknowns, but if you cruise long and far enough, you’ll inevitably pass the point of no return where, no matter what the report says, you have to make the most of the weather you’re dealt. Use all the technology to your advantage and make sure to keep in close contact with your weather router during your passage, but also beware of waiting for the “perfect” window. You may never leave the harbor.
Weather rules of thumb
- Highs generally indicate light winds and settled weather. Lows generally indicate high winds and stormy weather.
- The greater change in pressure or the shorter distance over which the change takes place, the stronger the pressure gradient and hence the wind will be.
- In the northern hemisphere, winds circle counterclockwise around an area of low pressure. In a westerly tracking Low, the strongest winds are usually near the center and on the southern side of the low. Winds circle clockwise around a High.
- Lows typically move faster than highs. When a Low overtakes a High, the pressure where the two systems meet gets compressed. This compression (isobars get closer) increases the gradient and wind strength. A steady barometer and rising wind speed (the conditions we experienced) is usually an indication of sailing parallel to an isobar line in a compression zone.
- Winds often follow the isobar curves of highs and lows on a weather map. The steeper the pressure gradient (the closer the isobars are spaced) the greater the curves will affect wind speed.