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A cool new tool for passage planning Messages in this topic - RSS

Simon Currin
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4 days ago
Simon Currin
Administrator
Posts: 679
Dick
I Googled Commanders Weather and found them at https://www.commandersweather.com/about Their pricing is considerably more affordable than the service we occasionally hooked in to. Thanks for the tip. We will try them out.
Simon

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Simon Currin
S/V Shimshal simon@medex.org.uk
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Dick
Posts: 225


4 days ago
Dick
Posts: 225
Hi Simon,
I think your using an experienced shore based person is a great idea and can be expanded as it meets with success with you and others. I can remember being in far-flung anchorages where I had the only wx input as I was the only person with SSB/Winlink. I had people dropping by every morning for updates. For the years I was in Central America, I received an email every day from paid wx forecaster which was invaluable (cold fronts rarely pushed that far S, and were hard to forecast, but when they did, one needed a couple of days warning often to get to a safe anchorage). I suspect that, in this era of internet, much of what he did for me then could be duplicated by a shore based amateur with access to the internet.
As to paid wx forecaster/routers, my team (Commanders Weather) had, I think, a rather easy time of it. They did 3 legs: Faroes to Iceland, Iceland to Greenland and Greenland to Canada and the weather was basically good for passages and as predicted: no surprises. As said in an earlier post, they were there as back-up as I had family along and it was not just Ginger and me. They validated my departure forecast/ routing which was reassuring, but not critical. They were uncannily more accurate than I was along the route at predicting wind shifts and speed increases: they had it almost to the hour where I would be looking at things changing during the evening watch. Nice, but certainly not critical (except racing maybe). I wanted them backing me up for complex wx (2 lows, for ex., coming together on the route in un-forecast ways) where I would be at a loss and that just did not occur: for which I am grateful. Although I do not feel that they were “tested” with challenging forecasting/routing, I would use them again.
My best, Dick Stevenson, s/v Alchemy

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Dick Stevenson, s/v Alchemy
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Simon Currin
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Posts: 679


4 days ago
Simon Currin
Administrator
Posts: 679
Dick
Agree with all your points.

A recent drive through London guided by a phone App left both Sally and me pondering how we ever avoided crashing when driving with a London A-Z on one knee and half an eye on the road 30 years ago.

The message is that we should all try to get a thorough understanding of the science and inform our decisions with as many data sources as possible.

We too retained the services of a “pay as you go” professionally router last summer but found his forecasts no more informative or accurate than our own and so rarely made the call for additional advice. When we did use him I think we paid a lot for what we got.

I am really looking forward next summer to sailing with a virtual volunteer senior OCC member on board to aid our decision making. He too is delighted by the prospect of a vicarious adventure now that his own boat is sold. So let’s hope that this new service will grow and build bonds between active and inactive cruisers. Much to gain for both parties and no money involved!
Simon
edited by simoncurrin on 12/6/2017

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Simon Currin
S/V Shimshal simon@medex.org.uk
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Dick
Posts: 225


5 days ago
Dick
Posts: 225
Hi Simon,
I finally get back to you with regards to the very thorough and well-argued post regarding routing/weather programs on computers. It all makes sense to me with a couple of thoughts to share:
1. Agree completely at the speed with which 500 mb upper-atmosphere forecasting knowledge and understandings flee from my head after I close the book. I also think that these learnings are very hard to implement unless you immerse yourself in them on a regular (daily) basis.
2. I believe that this software will serve a skipper best after a thorough grounding in conventional methods of analyzing and projecting weather trends and weaving in the likely sailing speeds and directions attained. This argument is very similar to the argument about having a thorough grounding in conventional plotting and navigation methods (parallel rules, dividers and such) before allowing charting software do the work.
3. When computers do the analyzing of data, there is a powerful tendency to treat said data as gospel. When you work from more original/primitive sources you are more likely to keep in mind its limitations. Again, this is similar to charting software where there are disasters every year attributable to relying on computer charting data as always accurate.
4. Immersion in working with data has hidden (and ancillary) benefits. I suspect I feel more connected with the “big picture” of weather and routing possibilities which might hold me in good stead when things do not unfold as forecast. I am reminded of recent extended stay in Washington DC where I was directed to all destinations by phone rather than pouring over maps and learning my way around as I would have in the past. As a consequence, I have learned little in 6 weeks in WashDC about the big picture. I did get around from the get-go without a problem, though.
5. When it comes to actually crunching numbers, I find the vagaries of the actual speeds attained and direction gone when sailing, along with the variations in the actual weather encountered to fit well with a more seat of the pants approach.
6. None of my above thoughts are in any way condemnatory, merely caveats to be aware of. I think one can conduct safe passages using computers as guidance systems for sure. I do believe that there are often “better” ways and “less good” methods, but that mostly it come down to the skill of the skipper and his/her willingness to do the work necessary to conduct safe passages. For example, I use charting software almost exclusively nowadays as it has proved its accuracy, ease and effectiveness and I also work hard to remember its limitations. I try to approach every tool in the same manner.
I plan no long seas passages in my future where I can test this out, but at this juncture, I suspect I would continue to do routing and weather the way I have always done it and spend my money on a professional router/weather group to look over my shoulder and augment. It feels like more bang for my buck and, I would expect the professional weather/routing people to have access to far more data, have the benefit of a team of meteorologists, and generate more nuanced suggestions than I could on my own and that a computer program would generate. This might be wise (money considerations aside) even if doing the computer weather/routing as then you would have an “in-house” suggestion and a “out-of-house” report. For the higher lat sailing we were doing this summer, a belt and braces passage making approach might be wise. As said in another post on the Forum, this worked well for us this past season.
My best, Dick Stevenson, s/v Alchemy

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Dick Stevenson, s/v Alchemy
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Dick
Posts: 225


19 days ago
Dick
Posts: 225
Hi Simon.
I have once-overed your very thorough reply. Thanks very much for it. And I will absorb it more fully in the days to come and reply. My best, Dick

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Dick Stevenson, s/v Alchemy
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Simon Currin
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Posts: 679


21 days ago
Simon Currin
Administrator
Posts: 679
Dick,


I followed with interest the recent discussion on another North American forum about weather routing software and noted, with some consternation, that these algorithms did not find favour. If I remember correctly the reasons given for dismissing such services were lack of upper atmosphere pressure charts and mistakes made when entering the polars for individual boats. Programming the polars is pretty easy in my view on a cruising boat as we tend to cruise conservatively when offshore. I remember understanding upper atmosphere charts when I read up about them in 1999 but, I confess, by 2000 I had forgotten all that I knew.


With the above two caveats dealt with let me explain why PredictWind works for us:
  • Like most digital offerings it is somewhat less prone to error than I am. Projecting boat speed in variable wind conditions manually over the course of a multi day passage in order to determine what the weather will be a like at a far off waypoint will introduce all manner of human variables. Why not just let a computer algorithm do the job fr you?
  • Predictwind automatically computes the panned route using two different global weather databases, ECMWF (European Centre for Medium-Range Weather Forecasts) and GFS (Global Forecast System), and presents them graphically so, at a glance, it is possible to see whether or not they concur. If there is a high degree of divergence then the forecast is likely to be less reliable. I’m not sure that most regular GRIB readers would enable concomitant plotting of differently sourced GRIB.
  • It is quick, easy and data light so work effortlessly on 3G, Iridium and regular internet regardless of device. I can drag in a detailed plan on my smartphone if I want and I am not dependent on a single laptop or PC.
  • Because it works so well and the algorithm can be run in an instant the planned passage can be remodelled effortlessly as often as I like as the baseline data changes.
  • The software and animations are really well written making it pretty well idiot proof with an attractive interface.
  • Subscription rates depend on the level of data required but for unlimited access during our summer cruising season the cost is not a barrier. It would be a greater concern if we were using it all the time.
  • Use of such software does not preclude the use of other data and tools. It is always prudent to source key safety information as widely as possible and to apply common sense to what you see. Why would you want to be deprived of such routing software to second guess your forecasts?
  • The departure planning functionality is very quick and easy and kept us out of troublesome headwinds all summer.
  • The summary table is most useful in deciding when a passage is viable for us or not. At a glance we can predict, so far with a high degree of accuracy, what percentage of the voyage will we to windward, on a reach or down wind. We can do the same with wave height, wind strength, precipitation and current.

I know all of this can be done manually or semi-automatically with GRIBS, a barometer and a synoptic chart. But why not use a computer for what it does best and that’s crunching numbers? I think the arguments against their use are specious and I was a bit unhappy about the way one of the authors of PredictWind was slapped down on another Forum.



Simon


Dick wrote:
Hi Simon and everyone,
Please educate me.
I few years back I ran some simulation/demos of the electronic weather routing programs and, although they certainly streamlined the process, I felt the end routing result was not any better than my working the gribs and surface weather forecasts. In fact, I felt that I was shortcutting (maybe) a process that allowed me to more deeply understand the weather patterns and better respond to changing conditions over the days of a passage and have a sense of the chances of things being different, especially the possibility of problems, such as a front coming in faster than anticipated.
There was that and then they were pricey and I could get gribs and surface forecasts underway.
What am I missing? What caught your addictive potential?
Thanks, Dick Stevenson, s/v Alchemy


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Simon Currin
S/V Shimshal simon@medex.org.uk
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Dick
Posts: 225


21 days ago
Dick
Posts: 225
Hi Simon and everyone,
Please educate me.
I few years back I ran some simulation/demos of the electronic weather routing programs and, although they certainly streamlined the process, I felt the end routing result was not any better than my working the gribs and surface weather forecasts. In fact, I felt that I was shortcutting (maybe) a process that allowed me to more deeply understand the weather patterns and better respond to changing conditions over the days of a passage and have a sense of the chances of things being different, especially the possibility of problems, such as a front coming in faster than anticipated.
There was that and then they were pricey and I could get gribs and surface forecasts underway.
What am I missing? What caught your addictive potential?
Thanks, Dick Stevenson, s/v Alchemy

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Dick Stevenson, s/v Alchemy
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Simon Currin
Administrator
Posts: 679


26 days ago
Simon Currin
Administrator
Posts: 679
Daria,
It looks very similar to PredictWind’s offering which we have become completely addicted to over the last three seasons. What’s different is that the have tried to shoehorn it into InReach’s meagre data capability. I can’t imagine how it looks and feels in InReach but I look forward to finding out.
Simon

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Simon Currin
S/V Shimshal simon@medex.org.uk
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Daria Blackwell
Posts: 707


26 days ago
Daria Blackwell
Posts: 707
If this isn't the coolest automated tool for route planning...not sure how reliable and I love their disclaimers. Any experience with it out there?

https://www.fastseas.com/

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Daria Blackwell - Rear Commodore, PR Officer, Editor OCC Digital Comms & Port Officer, West of Ireland s/v Aleria http://www.coastalboating.net
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