The reason for the brief update yesterday is all because of too much wind and not enough wind, or rather because the Skipper and First Mate/Chief Technology Officer, spent hours studying the vagaries of the developing weather situation along the North American seaboard from Florida up to Newfoundland and the implications for Bonny's travels and travails.
The Graphic below shows a high level view of the situation as forecast by the USA's National Hurricane Centre - but please note this is NOT a hurricane, but a disturbance that has less than a 40% chance (the lowest metric) of developing into one. A fuller explanation is given in the text beneath the graphic which you can zoom in on.
The core of this system is a developing area of low pressure, which the various weather forecast models show will track north eastwards up past Nova Scotia over the next week or so, bringing strong winds with it. These circulate in a counter clockwise direction. This means that Bonny's position, relative to the centre of the low, once it is within roughly 75 miles of her, will determine what wind direction and strength we will experience.
Bonny has been in an area of no wind for the last 30 hours and has been motoring northwards at between 4 and 5 knots in an effort to arrive off the coast of Nova Scotia before the worst weather arrives.
We have two challenges to manage. The first is that our fuel supply is limited to about 3 days of motoring and we must make sure we have fuel to burn for about the last 24 hours. This is not just so we can manoeuvre the boat in confined waters with no or contrary winds, but because we may also need to use it to generate electricity to power the ship's instruments, including the radar. Fog is an ever present risk in these parts and radar will help us spot vessels not transmitting on AIS (fishing boats often don't and apparently many yachts in these waters don't use it for some reason). Fog of course means we can't use our solar panels to charge the batteries!
So we can't afford to run out of fuel close to the coast. The catch, of course is that we don't have enough to simply 'steam on' regardless. If we did we would run out before we got there! So we have to decide when to stop the engine and simply wait for the wind.
Welcome to challenge number 2. The developing weather is currently very unpredictable. The forecasts are changing at every six hourly update. So far, the one thing the updates have had in common is that calms are predicted to follow Bonny to every possibe wind area within range, as if she was a magnet. Every area of wind we find in the forecasts, evaporates just as we predict Bonny would be most likely to crawl up to it at a sedate 4 knots (the maximum speed we can assume because of the fuel situation)! To say it's frustrating is the understatement of the century. I'm almost convinced that maligment forces are at work!
One piece of good news is that we have now crossed the notorious gulf stream which can flow up to 4 knots in these parts. It may not sound that much, but gale force winds against or even across the stream's direction, can give rise to very unpleasant seas. It's one joker that 'the force' has played to early!
Another positive is having Vince on board. Never have I encountered a situation in which slick IT user skills have been so helpful. One of the benefits of running the engine continuously, is that we have unlimited electricity to power Starlink (and to make and heat water - I had my first hot shower for a year today). That means we can use the Windy App and in less than an hour of playing with it, Vince bought the Premium version and mastered it's features; enabling us to run a range of course and speed scenarios against the developing weather situation.
Unfortunately, thus far, each one ends with 'the force' declaring 'check mate', but as the main event closes in on us, our decision making will be as informed as it's possible to be.
It's such a shame Windy doesn't provide a download option, because it's features are so superior to PredictWind's standard Offshore App; the principle App for offshore sailors. To 'enjoy' its premium features, one not only needs a subscription - fair enough - but also extra bits of expensive physical kit. I suppose Windy must run its processes on its servers where computing power and storage are virtually unlimited, rather than on one's relatively low powered hand held device.
So that's the situation. I'll try and continue to post daily updates.
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