2017 Weather to the Azores

[barnakiel]

Arghhh. Something happened in my browser and when I click 'reply' I do not get the inline text.

But - yes - many heads, many experiences and many attitudes to otherwise plain and not at all too complex a problem - how to get from A to B in the safest manner. Substitute 'safest' with 'fastest' - for racers and here we have the whole universe of viable solutions and more than one recipe for how to achieve this.

And now I will make another pass with Edge to see if I can post a quoted text.

BTW A couple of days ago I wanted to post an animation and it did not work either (Firefox) but it works in IE. Not sure what my problem is.

Cheers,
b.

[barnakiel]

Originally Posted by donradcliffe

Interesting stuff. I have a friend with a boat in Lanzarote who wants to come to the US in in the next month. I did it one April and had to go down as far as 14N to get wind. Stopped in St John and Ft Lauderdale, and it was a long boring trip, but nothing got broken. Would you suggest he take the southern route, or wait til Mid May and take a more direct route?

It is all dependent on what boat it is (a light /or racer vs. a heavy motor-sailor) and then on the wx patterns present at the time of your friends departure.

Statistically, there is no need to drop S at all - one could just head Westwards from here (Canarias), go as far as the wind allows, then (ghost or motor - boat specific) and some 500 or 1000 miles onwards you get the SE wind taking you all the way to the US coast.

However, as you experienced during your own passage - not every year the weather patterns are close to the long term averages, one may be forced to go S (20N is common, 15N is extreme) to find some wind - this is more penalizing if the boat being sailed is not optimized or not designed to do well in light broad reaching/running conditions. 'Some wind' is 20ish for a heavier boats but 10-15ish for a light and beamy boat that can and will carry a kite well.

I say 'penalizing' as you will notice at this latitude the orthodromic is way curved to the N. By sailing a S curve, we sail extra miles.

So, more briefly:

- per long term averages, one does not have to drop S departing Canaries for the US - in May,
- wait for your departure, then make your final decision based on what the patterns are doing - and play accordingly,
- if the boat is a heavier cruising boat that does not excel in light broad reach / downwind conditions under a kite: keep on the S edge of where you believe the wind corridor is. The same applies if the boat is very small or otherwise prone to shedding wind (e.g. Colin Archer like designs).

You can nudge me with a PM any time in May to discuss the conditions at any given time - I will try to be active in this thread till late May. I do not monitor the E-W route in May daily but the extra time and attention is minimal and I will discuss and share what I can see and what I think is happening with pleasure.

PS Possibly, but this is not confirmed at this time, my clients will be crossing E to W in a 72' sloop in May - Gran Canaria to the West Indies. If so, I will keep a record of their conditions as encountered on the passage. I can then share some insight into what conditions they encounter / which route was optimal in May 2017.

Cheers,
barnakiel

[barnakiel]

Originally Posted by estarzinger

This is perhaps a key point where we differ.

My perspective is that ALL have some information content - and that none (of the sort we are talking about here) are exactly 100% accurate.

The user's challenge is to correctly extract the information content.

This is why I said above I believe the key skill to develop for a cruising navigator is the ability to judge the confidence level in a specific forecast.

In short, I do that by looking at three things (1) is the pattern consistent over time (eg did yesterday's multi day run look similar to today's), (2) are different models showing similar pattern (eg do GFS and Euro look similar), and (3) does the particular specific pattern lend itself to confidence (eg isolated systems of distinct pressure tend to have much higher confidence pattern than either large areas of slack pressure or complicated system interactions).

If you conclude that the pattern has high confidence you can route close to systems and take advantage of the details. However if you conclude it has low confidence then you stick closer to the rumb line, pretty much ignore the micro details and just avoid the big bad stuff.

When looking at the tail end of a long range forecast you are obviously going to place less confidence in the micro details. You are looking simply to see if you should edge to the left or to the right to be better positioned to take advantage of things that might develop. Again, my experience is that there is often sufficient information content and confidence to make such a choice (and the vendee and volvo Nav's agree).

Also, as I said, it is easier to play cleverly with systems when you are sailing a north/south axis than an east/west axis.

In any case, I have had my say on that . . . .

Gloria! I can quote again.

Yes. I can see now more clearly your work flow. I got a bit lost in the earlier posts, also a bit due to fighting my browser while trying to follow your arguments. I am a visual beast and before I build a 'scheme' or 'flow' (be it in my mind only) I do tend to be a bit everywhere with my impulse reacting to the ideas like a cat will react to a moving object. But other than that, I have very low respect for cats (feline, not Catanas).

But I am back on track now, I hope.

I think we have vastly differing methods but this does not say anything about how different our results are. They may as well boil down to ending up with very similar findings and not very different conclusions. I also believe you are using a more scientific (or more correctly - a scientific) method while my own take is more based in minimum-complexity policy.

It would be very very nice if one day we could make the same passage at the same time in alike boats and equipped with alike weather data. Not that it could be conclusive in any way, but we could have a hell of a ride discussing the hows and the whys of our techniques and see where they took us. One only grows when new alternative ideas are brought up.

Which brings me to suggesting to people who read in this thread that joining one of the passage nets may be of help too. We do not have a transceiver in our small boat but we did listen to the Spanish net last time making this passage. It was (possibly still is) held by a Spanish wx 'guru' from here and we felt quite comfortable listening to the forecasts as well as getting the feedback on what the wx is doing. We always sail it low line and so all wx reports came from our windwrad side - a very very assuring thing, I must admit.

I know such nets exist in English, German and Swedish (for sure), possibly in French too.

So, this would be splendid if you could possibly find enough time and post what you find the weather on this stretch of the ocean is going. I started last year's thread in reaction to Atoll's earlier threads where the accidents and the weather were discussed for this part of the ocean and for this specific passage. My idea is that maybe by collecting the wefax / grib and otherwise wx data and insights / opinions we could make this passage less of a guess work /memory / opinions and more of a fact and data based experience. And nothing altruistic in this either as I too hope to be making this passage again, hopefully soon.

Great thanks for bringing up all the points and sharing your experience!

Very best regards,
from LPGC
barnakiel

[MarkJ]

Don't go too early! A 62 foot sailing boat sank last Wednesday in heavy conditions at Silver Banks near Turks and Caicos. Both crew saved.

[Palarran]

Today I reset my start point to where it showed I should be when I ran the route last Sunday. So here is last Sundays forecast for today (Wednesday) and todays forecast.

[Palarran]

Here are the next six days of forecast winds.

[barnakiel]

April 27.

NWS chartlets so that we do not need to browse the archives:

The forecast envisions a nice fat High cell that would screen the passage area from gales. The same would imply light conditions and flat seas for a boat on the direct route.

Cheers,
b.

[Palarran]

Barnakel sent me the folloing pm. Comment: If the forecasts are correct then virtually the track leading now Northwars FAST and then flatlining to the Azores would be the one to chose. Cheers, b.

I believe the track he is refering to is the Yellow one based on the European model. When I had run the route last Sunday this is near the same route as now and is pretty different than the other three. I would agree with him, but not because I'm smart enough to know 100% why due to the forecast. I'd sail this course because it keeps me more southern and would be easier to sail lower if the conditions developed worse than expected.

Based on the closeness of three courses, that should indicate a higher level of confidence in the forecast.

[barnakiel]

It is done in the following manner:

If there are no gales forecast in your selected X range:

- at each 'now' point (new forecast received and processed into a wx route) select the one that gives you the fastest ride to the target over the whole forecast period (here we assume the long term forecast to actually happen),

- reload, repeat.

Otherwise:

You will select your own X and this will vary depending on where and who you are. The X can also float: you can use 6hrs slots if the boat is sailing in an area with an active tropical depression or a dynamic N Atlantic system. You can opt for up to 48hrs slots - e.g. a cruising boat in the trade winds, in the 'good' season. Note that this can be on the same passage.

This is why you want to avoid analysis & routing at more than 24hrs periods (N Atlantic crossing W to E, any time of the year) - PLENTY can go 'wrong' in between. Think of NOAA updating their forecasts each 6 hours. You are missing 8 opportunity slots by working every 48 hours.

And this is where your safety margin steps in. If you can only get a forecast each 48 hours, you can chose more margin from the possibly disruptive areas (e.g. sail further S). But you will agree that one can get a gale tracking from NW but one can also get an ex-tropical Low (storm or hurricane) from S or SW.

It all gets more complex when we get from theory to practice, huh?

And this is just a dry exercise. When you have clients out at sea or when you are in the actual boat, it quickly become not just an intellectual adventure but an emotional ride too.

So a land based router (even if just a wx fluent sailing friend) can be such a great help. The analysis is done per schedule (often each 12 hours) while the skipper onboard can relax somewhat and concentrate on driving the boat to her full potential. A team work, of sorts, with part of the team shore based = fast Internet, sound stomach, alternative sources, etc..

When everything looks fine in 18:00 data, I only miss the 24:00 slot - one does have to sleep too.

Cheers,
b.

[barnakiel]

April 30.

NOAA sources show a long and nasty front to wipe over the whole area in the 48hrs forecast. Very rough for those higher up and to stretch way to the S for a time. Seen 50+ knots gusts in this grib.

Interestingly, at this point the general picture is of a (suspiciously?) large High stretching across nearly all the central area.

Cheers,
b.

[barnakiel]

It would be extremely interesting to hear from Palarran on how his software managed this upcoming front. The front was not forecast in the long 14 days gribs at the start of the exercise.

b.

[Palarran]

I just ran Predict Wind's routing forecast. Here it is for Now, tomorrow, and Monday. I moved my start point to where my last projection and the route I would have chose showed. I have my setting for routing to avoid winds in excess of 35 knots.

[Palarran]

On my last (only) crossing we were approximately at the position shown on Monday when we were hit with winds that never went below 40 and mostly hovered at 48 knots for about 72 hours straight. From NNE. It totally sucked.

[donradcliffe]

Thanks for the observations on the East-West route. I haven't seen my friend in a week, so he may have flown back to the boat in Lanzarote. The boat is a 65 ft unstayed cat-ketch, designed for performance, but also has a motoring range of 2000 miles. Looking at the forecasts, I'd wait a week.

[barnakiel]

Huh.

Looks like the train is coming. I am attaching today's chartlet for today. You will notice the extra elongated High and the extra fast flow above it. I never thought about it but possibly such elongated Highs are very easy to penetrate for energetic features acting half way along the oval of the High pressure.

If so, then a hypothetical tropical Low traveling below the high could actually cut across it rather than continue along the bottom of the H pressure.

Some boats will make miles but they will not be easy miles.

At the tail end of the forecast front there will be intensive thunder and lightning.

b.