We were rocking along the rhum line aboard Cuyler Morris’s Morris 45 Firefly following the late fall escape route from Northeast Harbor, Maine, to Bermuda, and eventually on to Antigua. Cuyler is President of Morris Yachts and obviously a magician; he was bringing the boat south so he could spend the winter living and cruising in the Caribbean with his family. Myself, ex-pro sailor John Boone of Goertz Marine Technologies, and offshore newbie/chef James Lindquist went along for the ride.
It all started so peacefully. |
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 20’s apparent). We doused the code zero in favor of the full main and jib. As afternoon turned to evening, true winds in the high 20’s wound forward of 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 30’s—true. Need I say the ride had become decidedly less placid than it had been?
So this is what fighting upwind in 40 knots looks like. |
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 current) 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 first hand), 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 rage predictions and use that information to help determine the weather a cruiser will experience on passages longer than a 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 many boats could make. We saw a rosy long range forecast and took it for gospel. Having the forecast for 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 tell tale 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 of 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 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 metrological 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 tk reef and saw the pink houses of Bermuda under angry grey 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.
James kissed the ground when we finally arrived in Bermuda. |
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 a 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
Having this kind of experience is really a great challenge. You need to think fast so that you can be able to manage the problem with ease. Aside from that, you should never forget to contact your weather router so that you would be informed on the latest weather update.
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