East Coast to Bermuda Races

Various races to or from Bermuda are held every year. These include:

» Marion to Bermuda
» Newport to Bermuda
» Annapolis to Bermuda
» Bermuda One Two

Unlike the Marblehead-Halifax race where tidal currents play a key role, racing to Bermuda is hardly affected by tides but is significantly affected by the Gulf Stream. Having good knowledge of the Gulf Stream at the beginning of the race allows the navigator to formulate a strategy for crossing the stream and taking advantage of current eddies and meanders. Luckily the stream does not change rapidly so one can usually do well if you are unable to get updated stream information during a race. There are a number of free and commercial sources for Gulf Stream information. A good starting point is the Newport-Bermuda Gulf Stream and Weather page.

SailFast™ accepts Grib current forecasts in addition to predicted wind. Having both current and wind Gribs will yield the most accurate optimum routing. However if you don't have a Gulf Stream current Grib you can still use SailFast's routing capabilities effectively. Merely set the SailFast™ "finish" waypoint to the desired position for entering an eddy you are targeting or the stream, and the best course for getting there will be determined. Once through the stream repeat the process to the next eddy or the finish.

Gulf Stream current Gribs are not as readily available as regular wind forecast Gribs. A free source is the NOAA RTOFS model Grib. This is best obtained through Saildocs as explained in a tutorial article by Gram Schweikert. Alternatively Gulf Stream analysis can be obtained from experience meteorologists. In either case the same raw satelite, buoy and ship reporting data is utilized to estimate the current. Dr. Len Walstad offers a Gulf Stream Grib through www.commandersweather.com which has been validated to work with SailFast™.

Below is an example of a Newport-Bermuda routing solution. Both wind and current arrows are displayed. The optimum route first picks up the favorable East side of an eddy and then rides a long section of the stream before heading South towards Bermuda. The predicted ETA to the finish is 82.3 hours. The time between the blue isochron lines is 3 hours. It took slightly under 3 minutes to run this optimum routing simulation.

(Click any image for a larger view.)

The optimum route takes a big jog East to take advantage of eddies and the stream and we are sailing a lot more distance than a rumb line course. What happens if we sail closer to the rhumb line?

Here we have added an additional boundary line to restrict where we allow sailing, and the wind arrow display has been turned off so we can see the current better. The boundary lines are magenta dashed lines. Now we force the crossing of the stream to be farther West. The optimum route still takes advanatge of the first eddy, but once through the stream a much more direct course to the finish is sailed. The ETA for this route is 82.4 minutes, just 6 minutes slower than the fastest course! All things being equal, I'd choose this course since it covers a lot less distance and doesn't require hitting the stream just right.

Finally, let's see what happens if we ignore the stream altogether and set the current=0 for the simulation. Now we have the original boundaries and just the wind arrows. The best course is now close to the rhumb line, and it is only deviating due to wind changes. The ETA is 85.9 hours. This result isn't very meaningful because there really is a significant Gulf Stream to contend with, but understanding the course with the best wind can be instructive.