Avoiding coastal surf? How do you do it?

[wstu]

I use Windyty.com to see what the forecasted swell is going to be. There are 3 factors in determing a safe anchorage when it comes to surf break. 1) height of swell 2) swell period. The shorter the period the steeper the swell 3) bottom formation. I have been in Anchorage we're ahead maybe 8 foot swells coming into the Anchorage but because they were at 20 second intervals and I was far enough off the shore they were not a threat in anyway. The 1.3x formula given earlier is good for detemining whether you are out of the surf break. IMHO The backside of a wave is not dangerous it's the front side. when the period is over double the swell height it is just a slow up and down ride

[wingssail]

Originally Posted by Franziska

So, I do apologize sincerely. After all there is a symbol. Visible only when you are very very zoomed in and probably already amidst of it.
So I guess I will from now on always run two displays. One really zoomed in a lot and one overview.
Wasn't there a reef hit by a Volvo which had a similar background [emoji3] Attachment 175822

It is good seamanship to do thorough route planning before setting out, using all the resources you have (such as pilot charts, etc) and if you are in-port when you do this planning then the Internet has a lot of good surfing sites, for example. But whatever, you should know well in advance what the dangers are for any place you will be going to, not just notice it when you are already there and zoom in on the chart.

If your passage needs to be changed when you are already underway then you have fewer resources available but you can still do planning for whatever new route you are switching to.

Most coastal sailboat wrecks occur in places where the skipper would not have gone if he'd done to planning in advance.

[Katiusha]

If you look on the map, Nazare has a very unusual layout of the ocean floor: a very deep canyon cutting in to otherwise very shallow coast. Nowhere else in Portugal such a narrow canyon coming from such great depths exactly in the direction of prevalent swell exists. The closest is Setubal and possibly Cascais, but not as dramatic and from a slightly different direction.

Here is a good comparison of the two canyons:

[RaymondR]

Originally Posted by wingssail

It is good seamanship to do thorough route planning before setting out, using all the resources you have (such as pilot charts, etc) and if you are in-port when you do this planning then the Internet has a lot of good surfing sites, for example. But whatever, you should know well in advance what the dangers are for any place you will be going to, not just notice it when you are already there and zoom in on the chart.

If your passage needs to be changed when you are already underway then you have fewer resources available but you can still do planning for whatever new route you are switching to.

Most coastal sailboat wrecks occur in places where the skipper would not have gone if he'd done to planning in advance.

I notice I'm starting to get into the habit of zooming in and walking the course on my chart plotter when I put in a goto cursor or waypoint. It would be very handy if there was a function button included in the software which would allow this with one tap on the screen rather than all the finger scrolling.

[Franziska]

Alternatively run and display aside to each other two instances of the charting software. One of them very zoomed in.

And yes I agree do thorough planning before leaving. That's by the way what I was doing when the subject came up.

[Coromandel]

There is a submarine canyon off the coast of Nazare which means you have very deep water close to the shoreline. A big swell from the Atlantic gives excellent surfing conditions, but you would probably not want to enter Nazare at times like that. A mile offshore, though, you are in deep water and in no danger of getting swept ashore.

The entrance to Nazare is easy, the small yacht harbour is well-protected, and you can get a bus to the marvellous monastery of Batalha (Manuelline architecture) quite easily. It makes a pleasant stop along the Portuguese coast before you get to either Peniche or Cascais.

Fair winds and safe passage.

[phipseml]

Originally Posted by Katiusha

If you look on the map, Nazare has a very unusual layout of the ocean floor: a very deep canyon cutting in to otherwise very shallow coast. Nowhere else in Portugal such a narrow canyon coming from such great depths exactly in the direction of prevalent swell exists. The closest is Setubal and possibly Cascais, but not as dramatic and from a slightly different direction.

Here is a good comparison of the two canyons:

I spent a month or so in the Nazare boatyard during October-November 2016, which I can recommend for serious work on your vessel. They have posters from oceanographic surveys hanging there explaining the formation of the famous wave, which is indeed connected to the underwater canyons: after storm action in the North Atlantic, large swell comes in from the west close to shore without losing energy due to the deep canyon south of the headland with the lighthouse, then somehow (forgot how) gets refracted towards north where it hits the same swell coming from the west just north of the headland, thereby creating the big wave as peak+peak=gigantic double peak. This also explains why the famous surfing wave is such an ugly pile of water and not a nice, long wave, as where the waves cross is only at one point and not along a line. Hope this makes sense explaining that particular phenomenon.



In general, though, as mentioned throughout this thread, you have to carefully observe the topography and swell conditions, even though local anomalies do exist. Those are explained in pilot books or online resources. Coincidentally, I met Dody in her then still dysfunctional Tonga in Nazare who wrote this excellent description of how to survive along the Iberian west coast: https://www.noonsite.com/Countries/P...the-west-coast .



Good luck surviving!


Phil

[The Salty One]

Originally Posted by Dockhead

There is no need to mark surf on the charts -- it's obvious from the depth contour. Why would you be "hugging the coast"? 90% of the dangers of navigating come from land or stuff near land. Coasts are not for hugging! Stand off well offshore, especially the Portugese coast, at least several miles!

Agreed! Unless you know the area well and weather conditions are in your favor, stay offshore.

When cruising, I always stayed a minimum of 5 miles offshore, up to 50 miles offshore. You also have to take into consideration, shipping lanes, currents, etc.

Plan ahead, have accurate wind charts, study the waters, speak to locals if possible. Sailing is either a wonderful adventure or a direct route to Davy Jones locker.

[Jdege]

https://youtu.be/RoODi1GtXMM

Nos. 3 &5

[Franziska]

Phil thanks for the very informative answer and the link to Dodies article.
Good stuff!