Safe seas?

I'm in the Pacific Northwest, home of the infamous Columbia River Bar and frequent challenging weather systems. When contemplating crossing the bar and venturing into cruising along the Pacific coast, the common advice is always, "Be patient and don't venture out into rough conditions." But what is the threshold for rough conditions? Especially since boats vary so widely in size, shape, and power, it can be hard to apply one person's Nordhavn in Florida to another's CHB in Washington.

My Taiwan-style Ponderosa 35 with a semi-displacement hull and a single Ford Lehman 120hp engine *should* be able to handle reasonable coastal conditions. Anyone with similar style boats have any rules of thumb you use to determine what is reasonable? I heard one formula: sea swells + wind waves <= 10. Has anyone pushed beyond that, and if so, what were the results? Looking to build my knowledge before "learning the hard way".

I would add the frequency of the swells to your list. A 35'er can ride a 10' to 12' swell with no problem, IF the frequency is greater than your boat length, but when it gets less you will be sticking you bow into the next swell, not a good thing.

Can you expand on frequency vs boat length? Looking at a current weather report, I see swells of 7' at 10 seconds. Given I have a 35' boat that travels at 7kts, what is the ratio there?

There is a web site that will show you just about all the things about the weather has to offer. It will show you from current to 10 days out. ( https://www.windytv.com )
Since I'm not where you are, and can not see the sea state, all I can reasonably do is an estimate for your boat, and not knowing your skill and experience, I would think that you should make a run up to the bar, and see if the conditions fit into your skill level.

Thanks for the link, that's a slick looking site.

To be clear, my questions are specific to the capabilities of the boat, not the skipper.

Rule of thumb is that the boat can take more than you and your crew. It's all about venturing out and getting experience.The sea state that you are describing is two different animals based on whether you are heading into it or if it is a following sea. The fact that you are asking these questions tells me that you need more time with the boat to gain confidence in yourself and the boat. Their is no mathematical equation that you can rely on. Find someone with experience / hire a captain with experience in your waters and get some quality boating time in with that person on your boat. As an east coaster I have no experience in your part of the world but I know that the area can be pretty rough. Don't put yourself and crew into situations that will ruin your / their love of boating. You are asking good responsible questions so that tells me that you will do the responsible thing.

I'm no expert on open sea conditions.

Having done most of my cruising in trailer boats, I tend to be pretty conservative when rounding Cape Caution, crossing the Dixon Entrance, or traveling on the west side of the outer islands of the Inside Passage. For my smaller boats, something like max wind of 15 knots, forecast no more than 15-20 knots, max wind waves of 1 meter, and very importantly: tidal current not opposed to the direction of the wind if wind is much more than 10 knots.

One time in our C-Dory, we were very much surprised to find ourselves in following seas that were 20-30 feet, in wind of 20 knots at most. They were big swells, from a storm some time earlier way out to the west, that got a lot bigger as they bunched up hitting shallower bottom on the west coast of Chichagof Island some 40-50 miles NW of Sitka. Not big round swells - shaped like an ordinary wind wave in maybe 15 knots, but several times as big. And pushing toward the rocky shore.

The C-Dory did fine, taking no green water over the bow, but it sure wasn't a whole lot of fun. Lots of white-knuckle helm action, varying the throttle to crawl up the wave at 9-10 knots, then backing off to mush through the top rather than fly over it, and steering straight down into the trough to avoid broaching. After we finally made it back inside to where we could anchor and calm down, we talked with commercial fishermen (54' seiner and 38' troller) who were out in the same stuff. They hated it too.

I think the very light C-Dory was particularly good at big waves. She had a relatively rounded bow shape, and was not very likely to stuff her bow. Not sure our heavy 26-footer would have fared as well.


For another source: there are a bunch of tuna fishers who head out, sometimes 30-50 miles out, into the ocean off the Oregon coast. They're pretty well educated on the relationship between wave height and frequency. I've seen their formulas for a reasonable day, but can't remember them. You can find them on the ifish Salty Dogs website:

http://www.ifish.net/board/forumdisplay.php?f=28

This is a question, not a recommendation to the OP. I have heard other say that they like to see the wave period be at least as long in seconds as the wave height in feet. That has always seemed reasonable to me, but then I don't get out much. Those of you with more experience, what do you think?

dhays said:

This is a question, not a recommendation to the OP. I have heard other say that they like to see the wave period be at least as long in seconds as the wave height in feet. That has always seemed reasonable to me, but then I don't get out much. Those of you with more experience, what do you think?

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If it's wind waves, less than 10', I prefer to see the period at least 2 greater than the height. Not so much on the West Coast as you don't typically get the rough chops of the Chesapeake and other areas. Wind waves of 5' at 4 or even 5 seconds can be very uncomfortable there.

The PNW was our first exposure to days of small wind waves but 10' and greater swells. Sometimes it's the direction and combination too, are they combining directly with each other or are the wind waves hitting you differently than the swells. On windyty, you can separate the wind waves from the swell. Right now we're dealing with swell at 90 degrees, 2' at 6 seconds and wind at 70 degrees, 4' at 4 seconds, so combined we have waves at 80 degrees, 4' at 5 seconds. That's rather typical here.

At the moment just outside Columbia Bar, here's what you have. Wind, 280 degrees, 1', 2 seconds, swell 290 degrees, 7', 9 seconds. I would consider that very comparable to what we're dealing with, perhaps a little smoother, but more challenging on crossing a bar.

Only you can establish your comfort zone. Don't let anyone encourage you to go in something you're not comfortable with. Off the coast of Alaska, actually quite far off, right now it's 20' at 10 seconds. I can tell you I wouldn't recommend that.

dhays said:

This is a question, not a recommendation to the OP. I have heard other say that they like to see the wave period be at least as long in seconds as the wave height in feet. That has always seemed reasonable to me, but then I don't get out much. Those of you with more experience, what do you think?

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I've never thought of it that way, but having been in a lot of serious seas, I think that rule of thumb has a bit of merit. I mean, 5 feet at 5 seconds would be pretty sporty, but not horrible in a 40' boat. 10' at 10 seconds sounds a bit better to me, but still rather sporty. So maybe that rule of thumb could work. I'm going to try it this year and see.

Ken

Off soundings conditions are often much more tolerable than crossing the bar. IMO avoid ebb tides especially with onshore winds.. High offshore winds are never good and will make crossing the bar worse.

dhays said:

This is a question, not a recommendation to the OP. I have heard other say that they like to see the wave period be at least as long in seconds as the wave height in feet. That has always seemed reasonable to me, but then I don't get out much. Those of you with more experience, what do you think?

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Ensuring the wave period in seconds greater than the wave height is a good basic rule of thumb, but it is never quite as simple as that.

There are so many more things to consider. The relationship between ocean swell, wind waves and wind speed & direction, current speed & direction, and depth of water is all fairly complicated.

Open water conditions are much different than what happens when the sea meets the shallower shelves.

I am of the opinion it can only be learned by getting out there. Do it by taking small steps, slowly stretching your comfort zone.
A big part of improving boating skills is understanding the weather. A good boater understands how weather patterns change the sea state.

Watch the weather, watch how & where waves break; it's all part of the learning process.
So - get out there and look at all the conditions. Start small and slowly build up your experience. Make sure your boat and crew are ready for it.

2 big hints on boat preparation before venturing out in rough weather.
-Ensure everything in the boat is completely secure. Things will be shaken up. Ensure batteries, cupboard contents, hot water tanks, propane bottles, etc are not going to be rolling around when it gets ugly out there.
- Ensure fuel tanks are clean. Any crud which settled out on the bottom will be stirred up and cause problems when you least need them.

To be clear, my questions are specific to the capabilities of the boat, not the skipper.

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Many of the posts are focusing on your experience not your boat. Their answers are quite reasonable, surviving heavy weather depends as much on your skill as your boat. The suggestions to gain experience are excellent advice.

Specifically for the Columbia River Bar I suggest your initial forays be made on the flood tide. Ebb tides with onshore winds are when river bars are at their most dangerous. A big swell on the flood can turn into breaking seas in just moments as the ebb starts.

If you are very inexperienced think about going about it this way:

• Get a forecast and tide prediction. Make notes of same.
• Ease down to buoy 14 and see how you feel about things.
• If all is OK go a bit further and then try turning back up river. Learn how your boat behaves in a sea-way
• Start to gain some experience both with the bar and your boat.

As you gain confidence think of what it would mean to get caught across the bar and trying to come back in on an ebb tide with a strong onshore wind. I note that today the predicted max ebb current is 5.7 kts. I'm going to guess your boat is a 7 to 8 kt boat? That could take you down to less than 2 kts made good. The slow crawl to safety could take hours. All the while the breaking seas will be running up behind you much faster than you are able to travel.

Whatever you do stay clear of Peacock Spit and Clatsop Spit even on the calmest of days.

I'm not sure about the rule of thumb for wave height vw period everyone is talking about. The PNW coast is a fickle place. Often more than one wave train, wind waves usually coming from a different direction than swells. It can be a real washing machine out there.

I'd like to comment on the idea of running before the seas being a good idea. In my experience it is most definitely not. More comfortable than head or beam seas, but much more dangerous. You are far more likely to broach or pitch pole.

As for your boat I can only make general comments. Your watertight integrity is not really up to heavy weather. I'd think your windows and doors can be blown out by boarding seas. You don't have watertight compartments to control flooding. And you likely don't have a kick ass bilge pump capable of de-watering your flooded engine space in minutes.

dhays said:

This is a question, not a recommendation to the OP. I have heard other say that they like to see the wave period be at least as long in seconds as the wave height in feet. That has always seemed reasonable to me, but then I don't get out much. Those of you with more experience, what do you think?

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I think this is a good baseline, assuming you are heading into the waves. If you are heaving down wind, they can be a lot bigger and still be comfortable.

But the OP seems to be looking for a starting point, so here's what I'd suggest.

- Wind 15kts or less

- Wind waves period > height if heading into them.

- Crossing the bar or anyplace where there is current over about 2 kts, avoid going into the wind when the current is against you.

That should keep you out of trouble while you test out your own tolerances.

Thanks @Portage_Bay and @twistedtree for addressing my question directly! When your only means of access to the ocean is through what is widely considered the most dangerous bar in the world, advice to "get out there and try it" just isn't very helpful. It's only safe till it's not, and turning around half-way often isn't an option. It's good to have some baseline rules-of-thumb to start with, so that experience-gathering can occur within a relatively safe space.

schrater said:

Thanks @Portage_Bay and @twistedtree for addressing my question directly! When your only means of access to the ocean is through what is widely considered the most dangerous bar in the world, advice to "get out there and try it" just isn't very helpful. It's only safe till it's not, and turning around half-way often isn't an option. It's good to have some baseline rules-of-thumb to start with, so that experience-gathering can occur within a relatively safe space.

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Be careful taking anybodies "rule of thumb" because you are asking experienced mariners who may not realize what they have become comfortable with over time.

YOU have to learn. You have to start easy and build skills.

My advice is to go out in flat calm conditions first. Learn how your boat handles.

Then go out in slightly less perfect conditions. Learn how your boat handles.

Baby steps here. Remember you are learning.

If you have a specific bar you are crossing go watch other boats in various sea states. See what they go through.

Continue this learning process, slowly. YOU will not only build skills, you will learn where you and your passengers comfort level is.


I will not tell you what we go out in because as a newby you would get the crap scared out of you and probably never go out again. But to us, it's no big deal. Because we took baby steps. Because I learned over time to be a competent rough water Coxswain. Because my wife has over time learned that she is safe in certain water, and that it's just something we have to get through to get to our destination.

schrater said:

When your only means of access to the ocean is through what is widely considered the most dangerous bar in the world, advice to "get out there and try it" just isn't very helpful. It's only safe till it's not, and turning around half-way often isn't an option. It's good to have some baseline rules-of-thumb to start with, so that experience-gathering can occur within a relatively safe space.

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Most dangerous bar in the world? Widely known? What? Sorry, that's local exaggeration. Now that's ok, if it makes you treat it with respect. Not quite ok if it makes you too fearful. Actually the most dangerous is the one you're about to enter and you're not prepared for.

Just remember, the rules of thumb for us, don't make them reasonable rules of thumb for you.

You need to go in totally benign conditions and slowly work up. You also need to learn what various conditions look like and feel like. Right now 5' at 6 seconds means nothing to you. You need to look at some information such as windyty while out and look around you and say, so this is about 4' at 6 seconds. Ok, I can recognize it now and in the future and I know what it looks and feels like.

I think much differently regarding various conditions than I did five years ago. I'd say everyone on this site thinks differently than the next person too. I change thinking based on what boat I'm on as well. Also, based on who is with me.

It's complicated.
Waves can vary with wind, swells, tidal flow, large river runoff, tides meeting wind, tides meeting river runoff, local anomalies, and more.

Someone mentioned on a thread a while ago..."This is pleasure cruising"..if it isn't pleasurable, don't go.

I understand wanting a tried and true formula for a starting point...I would start slow and easy because you will occasionally get caught and this will provide some info as to what conditions are "pleasure" for you and your boat.

Ask any question in the TrawlerForum, and you're likely to get more opinions than there are members I'll make one more attempt to get this thread back on track...

I specifically posted this in the "Taiwanese Makes" forum, because I was specifically looking for comment from other Taiwanese trawler owners, and preferably in the PNW, who could share their experiences with their boats' handling in various sea conditions. Skipper skills and experience and planning are all very important, but are also very individual and have been addressed in many other forums. I'm simply wondering what Taiwanese trawler owners have found to be reasonable conditions for their boats.

5 foot steep wind seas and they start boarding my bow, not entirely dangerous, but uncomfy as heck and larger threatens my saloon windows.

Any short sea above 3 beam to and I want to drink heavily.

Swells, a totally different story and hard to say. By themselves they could be 10 to 20 and be interesting at worst, or they might make things totally uncontrollable from the wrong direction and just a bit steep.

I couldn't venture to say what a 10 foot swell with a 10 second period with a 3 foot wind chop on top may look like in your neck of the woods....but if that were predicted in my world...I would either stay in or head for a decent inlet.

A good friend spent years commercial fishing off the OR coast. His stories are amazing, as is his safety record. These are the guys you need to ask. Those that have done every Pacific Coast bar crossing dozens if not hundreds of times in 40 to 60 foot vessels. Plus they have loaded vessels and schedules to keep.

I can tell you though, no one crossing and conditions are the same according to him. You need good weather and sea state forecasts, tide and current information, river level data, recent storm history and moon phase understanding. Then listen to the USCG for current bar conditions. Not to mention experience and a sound vessel.

Ask Tom on Alaska Seduction too. He and his fellow Columbia River boaters know the bar crossing drill pretty well.