C-Dory Capsizing Part 2

[Gene&Mary]

Thanks for all your thoughtful, knowledgable answers so far......typical of the C-Brats. I thought I'd give a little background for my previous question.

We use our C-Dory mainly as transportation between Twin Bridges Marina and Center Island- out from the Swinomish Slough to Padilla Bay, out Guemes Channel, across Rosario Strait either thru Lopez Pass or Thatcher Pass. We go year around....many times its better in the winter than the summer.

While we have always watched the marine forecast, its only been the past few years that we have really tried to combine the marine forecasts with current tables. We have found that the current tables are better to determine conditions than tide tables. We will never go out in weather over 2-4' seas and really try to choose slack current during these "upper limit" trips.

What generated my question about "capsizing" is that last Saturday the forecast called for 1-2 'waves with a west wind of (I think) 10-15 knts. We got out into Guemes Channel (a channel running east/west) and were really surprised at the wave height. Running against the wind, at slack current, we didn't expect a smooth ride but still........ We were running close to the south shore and the waves were partially hitting the starboard side of the boat causing it to roll. We got as far as the ferry landing and turned back.

Thinking about it later we thought the wind velocity was greater than 15 knts but we thought a larger factor was the west wind. We thought that the waves really had a long distance to fetch up thru Thatcher Pass, across Rosario Strait and up Guemes Channel. We had hoped that it might smooth out once we got into Rosario Strait but later decided that it probably wouldn't have gotten any better.

So with all the experience out there-

What is the largest determinant of waves- wind, current, wind direction, current direction? I'm sure it probably a combination but.....

Are there reasons to run closer to shore or more out into the middle of a large channel like Guemes?

For those that are familiar with this area, is there a better route in a west wind....maybe on the north side of Guemes Island thru Peavine Pass?

Are there other forecasting tools to use besides the marine forecast and the current/tide tables?

Thanks

 

[DaveS]

I have cruised around the North End of Guemes and Cypress and then through Peavine Pass in order to avoid fog that was settled into Rosario Straits between Fidalgo Island and James Island. I've also experience the seas to be a bit more forgiving that way. However, you still have a brief stretch between Twin Bridges and Guemes that can be a "washing machine".
When David rests up from his recent trip to pick up his new 16' Angler maybe he'll be able to chime in on this, since he resides on Guemes and has far more experience with Guemes Channel than I.

 

[starcrafttom]

I always like it best when the wind and current are running in the same direction. Makes for a smoother ride in most cases. If this is not possible take the route that is the most out of the wind.

As for closer to shore or not, I always remember a clip from the movie 13th warrior . Hugh waves at night and high wind. The new guy says “we should be closer to shore" the Viking says "shore? This is no night to be close to shore" followed by big smile.

Being close to shore is not a comfort in my mind. Large waves moving into shallow water will always equal bigger waves. Now deeper water may be in the middle or near shore in the SJ's. I have gotten pounded in the area you are talking about and moved just a hundred yards or less one way or the other and found calmer water to travel in. This goes back to knowing the bottom and reading the water.

As you cross towards Thatcher’s pass from town there is a deep reef just south of Cypress Island. if the tide is incoming hard the area just before the reef and across the reef can be really bad. The south end of the reef is 50 plus feet deep but everything around it is 200 feet deep. As all this water pushes up the face of that reef it can cause a lot of bumpy water. If you turn south a couple hundred yards the water is a lot nicer. How I get there is always a product of the conditions at hand.

 

[Bryant]

My wife and I recently took our C Dory 22 to Friday Harbor. The tide was comming in and the wind was from the Southwest at about 20. I thought that would equate to wind and tide in roughly in the same direction so I went straight out Deception Pass and rounded Lopez Island on the south side. Big mistake. We had huge rollers all the way to Lopez. I tried hugging the shore and it was really rough. Turning North in the cut between Lopez and San Juan Island we got into white water and it was like being in a washing machine. At one point the boat was pointed straight up going over a 10 ft wave with other waves all around us. The boat handled it and the Honda engine kept going but it was very uncomfortable and quite dangerous. I won't ever take that route again. North from Deception Pass and the route that the ferry takes through the islands is much easier. I guess that we all learn something from each trip that we take and I learned that even with the tide and wind in the same direction can still be dangerous in big water.

 

[westward]

Saturday weather was interesting in your zone: As we drove to Skyline (to take the Paraclete to Decatur) we remarked that, given how rough Guemes Channel was East of the ferry dock, we were likely in for a rough ride across Rosario. Turned out not to be the case at all. The water across the Strait was much calmer than in Guemes Channel, pretty routine in fact. Must have had something to do with cross-currents and tidal flow at the entrance to the channel. It's an interesting commute you have, and you're wise to stay on top of water conditions. Also of use is the Decatur Shores Community Association Rosario Strait webcam for real-time Rosario Strait weather. Best, Mike.

 

[20dauntless]

We do essentially the same commute fairly often (not enough, though), from Twin Bridges to Sylvan Cove on Decatur Island. Generally speaking, we find Guemes Channel to be the worst part. In the summer there is often heavy traffic, meaning lots of wakes, and the current can run several knots. When the wind opposes current, the waves get much steeper and less comfortable. Tide rips also occur off of Thatcher Pass and it can get nasty around the south end of Cypress. Really you want to be on the lookout for any situation where wind opposes current, or in some cases if a big swell is rolling in against the current even after the wind has died down.

 

[starcrafttom]

Bryant, I think you are making a mistake, thou a common one, about which route to take. Its all about the conditions on any given day. I have taken every way to Friday harbor that you can in the last three years. All of them can be as brutal as hell and even undoable at times, other days they can all be as smooth as glass. None of them are inherently bad or good.

it’s all about knowing the conditions before you go. Before I leave the house I take a look at several websites that give me info on wind/direction, tide, and current. With this info i can make a discussion on where to launch and which way to go. As well as WHEN to go. a half hour before slack can be a lot worse than slack or even a half hour after slack. All that aside it quite often comes down to the lesser of evils and just going slow.

Remember that Wind, tide, current, bottom structure are all different parts of the puzzle and have different but equal effects and to make it really interesting three of them are in constant change. How are you at chess? This is why I like boating and fishing.

 

[Bryant]

On the east coast I went out Beufort channel and the seas were running aobut 14 ft but it was just a swell so although it was unconfortable it was not that bad.
The trip out to Friday Harbor on that day was dangerous. You are right aobut watching the wind and tide. I misjudged it that day. I thought that the wind blowing in with the tide would make it ok. As it turned out, it wasn't. Last summer I took the southern route to Lopez Island and it was flat as a table. When I tried it again with the tide coming in and the wind blowing it was really rough. The Northern route has always been calm so that's the way I will take from now on.

 

[Nainu]

I cant comment on your specific area, but wanted to make a point about the close to shore option. In Cook Inlet where tidal currents are rather extreme, if the current is running against the wind, you definitely want to stay close to shore. The current doesn't run as strong close to shore and makes a considerable difference in wave height. Unless you are in water less than 2X the wave height, water depth alone will not affect wave action.

 

[Pat Anderson]

Tom, why don't you (and anybody else) post the links for the web sites you won't leave home without consulting?

This is a NOAA site that we usually check, but the weather is usually better and the waves smaller than they predict.

By the way, Snohomish River cruisers - here is the prediction for this Saturday:

SAT
SW WIND 15 TO 25 KT. WIND WAVES 2 TO 4 FT. SHOWERS LIKELY
AND CHANCE OF TSTMS.

High wind, big waves and I think that is chance of "thunderstorms"...

The wind has been blowing pretty good here in Fall City this morning and it is raining, so maybe that prediction is not too far off for tomorrow.

Before I leave the house I take a look at several websites that give me info on wind/direction, tide, and current.

 

[matt_unique]

Well as you point out it is of course a combination of factors.

Waves rolling from deep to shallow water will grow in size.

The wind direction in open ocean is the single greatest factor of sea state. The farther the wind can blow over water (relative to your position) the greater the waves. Between Boston and Gloucester (MA) for example a wind out of the west (blowing over land before hitting the water) will make for calmer seas closer to shore. Farther out to sea the waves will be rougher of course.

When it comes to tidal rivers, slack is the best as you certainly know. We have an infamous tidal river flow here in MA at the mouth of the Merrimack River. Flood to Ebb tide (transition from high to low tide) coupled with wind out of the east, coupled with shallow water offers the trifecta for rough seas at the mouth of the river. Vessels capsize here several times a year....it's a given to see several reports a year and unfortunately there are some fatalities.

The first time I exited the river during this state was impressive. It was a good day to have a C-Dory....there was nothing but blue water spilling over the entire vessel when we went into the waves. At slack tide with calm wind I have seen this spot flat calm.

 

[Doryman]

The current issue of Lattitudes & Attitudes has an excellent article about weather windows. It discusses forecasts and where they come from. Basically it says to do what Tom is telling you, but it gives you a few more tools, or perhaps I should say heuristics, that you can use in deciding when to go or not go. Bottom line from the article is that you need to become familiar with local weather patterns for the area where you are going and learn how those observed patterns mesh with forecasts and real time data.

Warren

 

[Sea Wolf]

In San Francisco Bay, the current runs the strongest in the deeper parts, and also those parts where the channel drains/floods the largest area/volume up bay/river. These two areas generally coincide.

Therefore, the worst places to be are from the Golden Gate back to the south side of Alcatraz, and from the Gate down Raccoon Straight, both when the afternoon Westerly is howling and the current happens to be running out the Gate.

Go get a 14 -18 foot dinghy sailboat with a trapeze and try out the square 4 footers!

Hiding out near shore (and out of the severe current) is not allowed!

The real thing!


Joe. :teeth :thup

 

[Jazzmanic]

Bryant,

The route you're talking about is going through Cattle Pass, which can be a washing machine a majority of the time, even worse on an ebb. That's why I choose the inside route into Friday Harbor most of the time unless the conditions are fairly calm.

Tom is right, I've learned to pay attention to the winds and currents in choosing my route in the San Juans. Fred (Anita Maria) has convinced me that many times, the best way to the inner San Juans from Twin Bridges is up the east side of Guemes, across the top of Cypress and across Northern Rosario Strait to Pevine Pass. That's preferable to Guemes Channel in my book.

As to the original post, Gene & Mary, I know you have local knowledge due to the fact that you run that route everytime so it must have been something to get caught out in those conditions. It just goes to show that nothing can ever be taken for granted out on the water when you're dealing with currents and wind. In fact, our scariest moment was in Guemes Channel heading east from the Cap Sante Marina to Twin Bridges into Swinomish Channel. 5-7 footers close together with the occasional 8-9 footer, in very shallow water against an opposing wind made for a very scary ride!!!

 

[thataway]

I don't have anywhere the amount of experience in those specific waters as many of you. But the times we have gone along several of these routes, there seemed to be several factors--including what Matt and others mentioned above. There can be refraction of seas which come from the larger straits; The waves may summate, the currents may not always be as exact as the tide and current diagrams predict, and winds often accelerate between Islands and bend around the ends of islands and points.

It can get really nasty in many of these channels--and turning around, waiting for better conditions is often a wise move.

 

[DaveS]

The real thing!


Joe. :teeth :thup

Joe this picture brings back a flood of memories for me. Back in the 70's I dangled out on a trapeze on a 21' Olympic Class Tempest in this same location. We were on a quest for the Olympics.....however, we lost the race....broke a rudder and were "out sailed" by a couple of San Francisco chaps.

 

[Wefings]

Warren , straight from Wikipedia ;

"A simple example of how heuristics can fail is to answer the question "What is the next number in this sequence: 1, 2, 4?". One heuristic algorithm might say that the next number is 8 because the numbers are doubling — leading to a sequence like 1, 2, 4, 8, 16, 32... Another, equally valid, heuristic would say that the next number is 7 because each number is being raised by one higher interval than the one before — leading to a series that looks like 1, 2, 4, 7, 11, 16."

Gotta be prepared to be wrong and go with the educated gut feeling based on your most trusted sources [hopefully and ultimately decided by you ].Weather is the biggest wild card . Part of the attraction of the sea, seaside living ,boating,fishing , and perhaps the whole boat industry for me .
Marc

 

[jimandlaurie]

I'm kinda late to comment, but Laurie and I have experienced things like Byant has, more so when we had the '22. The bottom line was that we were in the RIGHT boat to handle it. We probably wouldn't be here if not in our C-Dory.

 

[Doryman]

Gotta be prepared to be wrong and go with the educated gut feeling based on your most trusted sources [hopefully and ultimately decided by you]. Weather is the biggest wild card . Part of the attraction of the sea, seaside living ,boating,fishing, and perhaps the whole boat industry for me.

This is certainly true. I think this is what the author was saying and it may have been my mistake to use the word heuristics. He definitely advocates getting to the point where you can make that educated gut feeling.

I would be interested in your comments about the article.

Warren