7’ to 9’ seas??? That’s nothing!

[swampu]

Ok, I read your post and realize I have almost none of the experience you guys have. Sounds like you are avid mariners and made a very thorough plan. My area of the northern GOM is definitely not as predictable as where you boat. If you had a few 11'ers in the mix than you were for sure in the good stuff.

 

[Bruce B]

I think that my tongue-in-cheek thread title was perhaps not the brightest title I have come up with. It is likely contributing to some confusion about the thread...
Bruce

 

[Bruce B Wifey D]

Ok, I read your post and realize I have almost none of the experience you guys have. Sounds like you are avid mariners and made a very thorough plan. My area of the northern GOM is definitely not as predictable as where you boat. If you had a few 11'ers in the mix than you were for sure in the good stuff.

We’ve made our share of mistakes. If you say you’ve never been aground you’re either lying or you’ve never been anywhere! ?

 

[Seevee]

We’ve made our share of mistakes. If you say you’ve never been aground you’re either lying or you’ve never been anywhere! ?

Bruce B Wifey,

And going aground is a whole nother thread that would be interesting. One of the early boats I bought was specifically for exploring the edges of going around... and good learning experience, but I wore the boat out.

 

[BandB]

Bruce and Dorsey know the difference and know 6-9' swells with longer periods vs. 6-9' wind waves with short periods and know how to judge and remain safe, just as we do and many others do, as they have extensive experience. I know many normally are dealing with wind waves and not swells. Our first introduction to very large swells was the coast of Washington. Our first day out was forecast 10' at 13 seconds. It was actually more, but it never felt unsafe at all and for the most part not even uncomfortable. Now, that was in an 85' boat also.

Everyone has to learn what the differences are and what they are comfortable with in their boat. At this moment we're in 4' at 7 seconds. However, to be more precise we have wind waves of 2' at 4 seconds and swell of 3' at 9 seconds, but actually three swells, one is 3' at 10 seconds, one is 1' at 9 seconds, and one is 1' at 4 seconds. All I can say with certainty is it feels very calm out here today, no worse than the 2' at 4 second winds would feel but all together giving a higher wave and much longer period. At 20 knots, a beautiful ride and our first time out in 28 days so we're ecstatic, even if it's just from FLL to West Palm for lunch with 10 of our closest friends aboard and our host meeting us there.

 

[psneeld]

Funny how everyone thinks their patch of ocean is different.

Anyone think physics or whatever the best describing science to wind and wave has to do with it versus geography?

Given similar waters, yes even salinity and temperature can affect wave formation.

But in the big scheme of things, most areas of boating can develope similar wave patterns or certainly wave of a certain steepness to scare anyone.

Hopefully we all stay out of them as much as possible...whether experience or luck.

Plus, depending on many factors of the boat and course mean a huge difference.....hard to compare apples to apples when describing or suggestions on sea conditions.

 

[BandB]

Funny how everyone thinks their patch of ocean is different.

Anyone think physics or whatever the best describing science to wind and wave has to do with it versus geography?

Given similar waters, yes even salinity and temperature can affect wave formation.

But in the big scheme of things, most areas of boating can develope similar wave patterns or certainly wave of a certain steepness to scare anyone.

Hopefully we all stay out of them as much as possible...whether experience or luck.

Plus, depending on many factors of the boat and course mean a huge difference.....hard to compare apples to apples when describing or suggestions on sea conditions.

Actually we think our patch is rather common, but we have been to other patches that were quite different. The Pacific Coast in general, and especially the PNW, is very different than the Atlantic Coast. I've found the Chesapeake to have it's own uniqueness. I also imagine and have heard Maine is very different, but haven't made it there yet to know further. Now when comparing to my home cruising area, I've really found nothing in the Caribbean to be significantly different. Only uniqueness is that you do have in the Eastern Caribbean a protective range of islands which often have bad conditions on the outside, the East, and calmer on the inside, the West. In some ways reminding one of the protection formed by the barrier islands between the ICW and Ocean.

Actually, I do believe geography has something to do with the swells of the West Coast vs. East Coast swells, that being that there is a broader expanse of ocean from there to Asia than between the East Coast and Europe.

 

[psneeld]

Of course major geographic regions are different, thats not what I was alluding to.

 

[MurrayM]

I think that my tongue-in-cheek thread title was perhaps not the brightest title I have come up with. It is likely contributing to some confusion about the thread...
Bruce

Yup. I read it as an introduction to a butt puckering video, then was underwhelmed. Dorsey's video in post #24 is more like what I was expecting...but it could have been about 3 seconds shorter!

 

[swampu]

Bahahaha

 

[BandB]

And to the main point of the thread, he was very happy with the performance of his American Tug and that's the best part.

 

[jleonard]

I use my fish finder to judge wave height when running over a flat bottom. Not much guessing, just read the numbers.
My personal experience indicates that most folks greatly over estimate wave height.

 

[SOJOURN4]

THOSE US US WITH 2 HELM STATIONS....
How many times when running the boat from the fly do you come down into the cabin and see an entirely different sea state?
Long period swells are always deceiving.....

 

[Gordon J]

You guys should read this entire description and educate yourself on waves and forecast. One day you will read a wave report and say 6' seas are no big deal and you will get caught up in a life or death situation. We're I live you don't play with the weather. It's shallow and there is a huge difference between a 6' roller and 6' chop.
https://www.mxak.org/weather/pdfs/waves.pdf

I appreciate the link. It was very informative. I have been boating for almost 20 years, including a lot of Bluewater sailing, and did not know what was meant in the forecasts. I would never of guessed that a forecast of 10 foot seas could mean that I might see a 90 foot wave.


Gordon

 

[Peter B]

I appreciate the link. It was very informative. I have been boating for almost 20 years, including a lot of Bluewater sailing, and did not know what was meant in the forecasts. I would never of guessed that a forecast of 10 foot seas could mean that I might see a 90 foot wave.

Gordon

Ah, no Gordon, that's not what it says, that highest wave is usually considered as up to 100% higher than the estimated average, so in 10ft seas, that would be 20ft, not 90. Bad enough, but survivable if prepared.

From the link you provided....
.....If you received a marine weather forecast predicting “SEAS 10 FT” in the coastal or offshore waters, what is really being conveyed in that forecast?
• Hs=10ft
• H (mean) = 0.64 times Hs = 6.4 ft
• H (most probable) (slightly less that H mean) = 6 ft
• H1/10 (10% highest waves) = 1.27 times Hs = 12.7 ft
• H1/100 (1% highest waves) = 1.67 times Hs = 16.7 ft
• Hmax (highest wave you should be on the alert for) = approximately 2 times Hs = 20 ft!

No need to scare yourself unnecessarily...

 

[markpierce]

The worst seas I've experienced were fifty-foot waves. Fortunately, was aboard a 900-foot ship and only experienced a sprained knee taking about a year to heal, leastwise when the pain stopped.

 

[BruceK]

Forecasts here from The Weather Bureau as published by Marine Rescue, a largely volunteer communications facility and rescue organization(oft called Dad`s Army after an old British TV series about the blundering Home Guard), are generally subject to a 50% above forecast allowance and warning.
Weather forecasts don`t always get it right. You can miss some great days, or drown, if you just slavishly follow them. PeterB nails the interpretation of the article cited.
It`s how you and the boat handle it. The seas in the OP`s vid don`t look 6-9ft to me either, but I wasn`t there. Certainly boat and crew seemed to be fine with conditions, but the descriptions suggest care and caution were needed.
I`ve been in (my estimate) 7-8ft short period beam on I did not really expect but www.seabreeze.com.au did. We headed up to take the bigger ones at a sharper angle, headed down when it was better, still ended several miles further offshore than usual before choosing a time to turn towards land and take what were then following waves on the quarter. I did not enjoy it one bit, we cracked a corner of a windscreen panel due to force or flexing, I worked hard at "keeping the boat on its feet", we were well challenged by some waves very close together.
It is impressive the OP carefully considered the course and the expected challenges along the way. More than anything, it is the good analysis and planning I take out of this.

 

[Bay Pelican]

THOSE US US WITH 2 HELM STATIONS....
How many times when running the boat from the fly do you come down into the cabin and see an entirely different sea state?
Long period swells are always deceiving.....

A Krogen 42 has four levels from which one can view wave height. The boat (upper deck), pilot house, cockpit (aft deck) and the foredeck. Sea states seem totally different from each of the first three. Generally I observe heavy weather from the pilot house so I am looking down at the normal sea level. Have not experienced the foredeck in waves above 4 feet.

 

[Coastal Cruiser]

Bruce B- You describe your experience in 6'-9' seas as "delightful. Most 39' semi-displacement boat owners would describe their experience in these kinds of seas in much less glowing terms.


Why is the American Tug hull better able to handle rough water?

 

[hmason]

When I read/hear a wave height forecast I make a go/no go decision by doubling the wave height forecast. I consider period and wind as well but that's my basic decision point. Maybe not the most scientific but has served me well for over 50 years. Besides, if I was in a hurry I wouldn't have a trawler.

 

[BandB]

When I read/hear a wave height forecast I make a go/no go decision by doubling the wave height forecast. I consider period and wind as well but that's my basic decision point. Maybe not the most scientific but has served me well for over 50 years. Besides, if I was in a hurry I wouldn't have a trawler.

Well, whatever works for you, but we would have missed a lot of great cruising if we'd done that.

 

[swampu]

I appreciate the link. It was very informative. I have been boating for almost 20 years, including a lot of Bluewater sailing, and did not know what was meant in the forecasts. I would never of guessed that a forecast of 10 foot seas could mean that I might see a 90 foot wave.





Gordon

My only point in posting the article was for new boaters like me. I fished off shore for ten years before my current boating lifestyle. When fishing tournaments you go no matter what, you learn to deal with the conditions given. Blue water anything is different than shallow gulf waters. All of you "experienced " gurus will get someone in a bad situation with all this great online advice.

 

[Group9]

Bad , steep seas are usually found at the Start of a blow , especially if there is little fetch.

15 ft swells , 200 ft apart after a storm has matured are a delight to go with.

Its the duration , time between bumps that counts.

Agreed. One of the most interesting and pleasant sails was 20 knot winds on the beam and 15 to 20 seas, 200 plus feet apart, when transiting from Chub Cay to Nassau one day. It was like riding up and down gentle rolling hills.

 

[MichaelB1969]

As long as we're on the topic, can anyone estimate the size of these swells? The first one seems bigger than the second. I know it is hard to gauge on video, but I think it captures it fairly well. This was coming back from Half Moon Bay to San Francisco last week.

I am horrible at estimating wave height, but the period seems to be 5 or 6 seconds (based on the actual timing in the video).

CORRECTION: Just realized that we were doing around 13 knots, so of course the timing between crests in the video is not the actual wave period. Sorry, need some coffee...

 

[Fletcher500]

As long as we're on the topic, can anyone estimate the size of these swells? The first one seems bigger than the second. I know it is hard to gauge on video, but I think it captures it fairly well. This was coming back from Half Moon Bay to San Francisco last week.

I am horrible at estimating wave height, but the period seems to be 5 or 6 seconds (based on the actual timing in the video).

https://youtu.be/ozKiMULLIAI

When on ships years ago, the biggest waves I ever encountered where in your back yard. I have some pics from a T5 oil tanker in 1986 outside the Golden Gate Beidge and we were getting clobbered. A barge sank near the bridge so the CG wouldn't let anyone enter until it was cleared.

As others have noted, it is so very hard to estimate from a video. Because you are taking them head on, and not much chop In between, I am thinking your video doesn't do it justice and it was bigger than it appears to us. With that said, I am going to take a swag and say 4 to 5.

 

[Mrwesson]

As long as we're on the topic, can anyone estimate the size of these swells? The first one seems bigger than the second. I know it is hard to gauge on video, but I think it captures it fairly well. This was coming back from Half Moon Bay to San Francisco last week.

I am horrible at estimating wave height, but the period seems to be 5 or 6 seconds (based on the actual timing in the video).

https://youtu.be/ozKiMULLIAI

I'd say 6' swells @ 10-12 seconds with a 1-2' wind chop. Very mild rollers in what looks like deep water.

The OP video may very well be 6' swells but if so they were at a very long period.

I'd call the OP's video 3' seas but that's on top of the swells(6' is believable) which makes look worse if that makes sense. 6-9' waves are a whole different thing that would make you turn green on a 60' sportfish.

6-9' waves would be putting alot of water on the deck(think zero visibility from spray) of any boat under 100'.

6' seas with a 3' chop sucks more than the video I quoted. That was a nice day IMO

 

[MichaelB1969]

I'd say 8' swells with a 1-2' wind chop.

The OP video may very well be 6' swells but if so they were at a very long period.

I'd call the OP's video 3' seas but that's on top of the swells(6' is believable) which makes look worse if that makes sense. 6-9' waves are a whole different thing that would make you turn green on a 60' sportfish.

6-9' waves would be putting alot of water on the deck(think zero visibility from spray) of any boat under 100'.

6' seas with a 3' chop sucks more than the video I quoted. That was a nice day IMO

I was in 6 to 9 foot waves in a 27 foot Silverton when I was a young teenager. Not fun! I was super nervous as I saw the entire bow disappear under water time after time. As we got over the crest of a wave, you'd hear the prop start whirring loudly as it came out of the water. It was the first time in my life I seriously thought I was going to die.

 

[koliver]

There are far too many variables in play to use just wave height as any measure of comfort.
In Johnstone Straight, I have been severely beaten up in 4' waves.
In the open Pacific 35' waves produced a very pleasant ride. Now the period of the JS waves was quite short and of the Pacific swells was very long, at least partly explaining the difference.