Stripers & Anglers Education Series,,,,groundswells and other terms...

[DarkSkies]

A good thing to know for fall fishing is that the water is sometimes rougher due to the Fall hurricanes and offshore swells.

I thought it would be a good idea to talk about it here, when last night I ran into 2 guys who told me they almost got knocked off a rockpile by a "rogue wave"

What we had last night, was a medium perod swell.

Medium Period Swell The past couple days waves have been in the waist to stomach high range and bigger sets with the period being around 7-9 seconds.

Short period swell is sometimes defined as between 1-14 seconds. Long period swell is sometimes defined as 14 secs or longer between waves from the crest to crest. Medium period fits nicely in the middle here. Remember that this is sometimes definable, and sometimes an offshore storm will throw thinigs off a bit at different stages of the tide. If you want to be safe, it's your responsibility to look for the patterns.,






That explains it a bit, but what does that mean? It describes the wave energy as travels from offshore to the surf line.



As a surf fisherman, one thing you want to be aware of is the duration. the seconds between each wave crest hitting the beach or where you are. Short durations are sometimes dangerous, and new inexperienced guys should not be out there. Longer durations give you better presentation time when fishing artificials.


I met 2 guys last night that told me they got "attacked" by rogue waves. :huh:
You can't get attacked by a wave if you have studied the pattern and are aware of it.


You need to learn to read the waves, and watch the "sets" (groups of waves)


As you do this, you will see that often there are waves among the "set" that are larger and more forceful. Usually this has a pattern.


When you are out there at night, especially if by yourself, this can mean the difference between a good night out, and a rescue or swimming lessons. :scared:


So study the sets, learn to recognize the patterns. and be safe...


If anyone has anything else to add, feel free. :HappyWave:

[surfstix1963]

I love watching the montauk boys continually get knocked off "THEIR ROCK":huh: it kind of makes you wonder #1 who the hell gave them the rock in the first place :d and how many times do you need to get knocked off a rock before you figure out your wasting more time on your butt then you are fishing:banghead2::banghead2:

[jigfreak]

I say at Montauk it is something to be expected because of the huge volume of water that runs past the point. In Jersey, you are out there, and you get knocked off a jetty by a rogue wave? Come on! Unless you are fishing a storm, as was said each set of waves at night has a pattern. Study them for 5 minutes and you will see the secondary patterns. It isn't rocket science. lads.

[storminsteve]

Here is another description of the swell right now, dark you are right on the money about it, it's tricky.

"The big ground swells have slacked off but there is now a chopped up short-period wind swell that makes ocean and inlet fishing a tad iffy."

[seamonkey]

Very informative guys, thanks.

[williehookem]

I got this from surfline.com, pretty cool stuff.


So how do we get surf, by Sean Collins
Swell Period.
The most overlooked three-dimensional variable. Most surfers look at waves from a two-dimensional perspective: wave height (javascript:glossarypop('surfology_glossary_index. cfm?target=wave height');) and direction. But waves need to be analyzed from a three-dimensional perspective, which also includes the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');). The swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) variable is the X-factor. It's the make or break variable and plays a huge role in the eventual size of a swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');). This is why:
<LI class=desc>Wave decay and travel. The longer the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');), the more energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) the wind has transferred into the ocean. Long-period swells are able to sustain more energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) as they travel great distances across the ocean. Short-period swells (javascript:glossarypop('surfology_glossary_index. cfm?target=Short-period swells');) (less than 14 seconds between wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) crests) are steeper as they travel across the ocean and, therefore, are more susceptible to decay from opposing winds and seas. Long-period swells (greater than 14 seconds) travel with more energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) below the ocean surface and are less steep (javascript:glossarypop('surfology_glossary_index. cfm?target=steep');) so they can easily pass through opposing winds and seas with very little affect.

<LI class=desc>Conserving energy. Swells travel as a group of waves or a "wave train." As the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) moves forward, the wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) in the front of the wave train (javascript:glossarypop('surfology_glossary_index. cfm?target=wave train');) will slow down and drop back to the rear of the group while the other waves move forward by one position. Then the next wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) in front moves back and another takes its place -- much like a rotating conveyor belt that is also moving forward. It's a process somewhat similar to the "drafting" technique used by bicycle racers and car racers, and it enables wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) trains to conserve their energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) as they travel great distances across the oceans. Working together to sustain energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');).

<LI class=desc>Wave speed. The speed of a swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) or a wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) train can be calculated by multiplying the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) times 1.5. For example, a swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) or a wave train (javascript:glossarypop('surfology_glossary_index. cfm?target=wave train');) with a period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) of 20 seconds will be traveling at 30 knots in deep water (javascript:glossarypop('surfology_glossary_index. cfm?target=deep water');). (Knots are nautical miles per hour. One knot (javascript:glossarypop('surfology_glossary_index. cfm?target=knot');) equals 1.2 mph on land.) A swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) with a period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) of 10 seconds will travel at 15 knots. The individual waves actually move twice as fast as the wave train (javascript:glossarypop('surfology_glossary_index. cfm?target=wave train');) or the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');), and a single wave's speed can be calculated by multiplying the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) times three. So individual waves with a period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) of 20 seconds travel at 60 knots in deep water (javascript:glossarypop('surfology_glossary_index. cfm?target=deep water');). Again, think of the wave train (javascript:glossarypop('surfology_glossary_index. cfm?target=wave train');) like a rotating conveyor belt that is also moving forward.

<LI class=desc>Forerunners. Long-period waves move faster than short-period waves, so they will be the first to arrive. Forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=Forerunners');) are the initial long-period waves that travel faster than the main body of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');). Usually, forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) are pulses of energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) with periods of 18 to 20 seconds or more. A wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) train's peak (javascript:glossarypop('surfology_glossary_index. cfm?target=peak');) energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) will usually follow in the 15- to 17-second range. The swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) will steadily drop during the life cycle of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) as it arrives on the coast. The farther a swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) travels, the greater the separation of arrival time between the forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) and the peak (javascript:glossarypop('surfology_glossary_index. cfm?target=peak');) of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');). Often the forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) will only be inches high but can be measured by buoys and other sensitive oceanographic instruments. To the naked eye, forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) are very hard to see; sometimes you can pick them out as slight bumps on a jetty or other rocks. Surfers with a sharp eye can often sense forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) as the "ocean seems to be moving" with extra surging and currents. Even though forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) may only be inches high, they constitute a large amount of energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');). LOLA uses real-time (javascript:glossarypop('surfology_glossary_index. cfm?target=real-time');) buoy (javascript:glossarypop('surfology_glossary_index. cfm?target=buoy');) data to separate these tiny forerunners (javascript:glossarypop('surfology_glossary_index. cfm?target=forerunners');) from the rest of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) in the water so we can identify the first signs of a new swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) -- before we can see it at the beach.

<LI class=desc>Swell period and ocean depth. The depth at which the waves begin to feel the ocean floor is one-half the wavelength between wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) crests. Wavelength and swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) are directly relative, so we can use the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) to calculate the exact depth at which the waves will begin to feel the ocean floor. The formula is simple: take the number of seconds between swells, square it, and then multiply by 2.56. The result will equal the depth the waves begin to feel the ocean floor. A 20-second swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) will begin to feel the ocean floor at 1,024 feet of water (20 x 20 = 400. And then 400 x 2.56 = 1,024 feet deep). In some areas along California, that's almost 10 miles offshore (javascript:glossarypop('surfology_glossary_index. cfm?target=offshore');). An 18-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) will feel the bottom at 829 feet deep; a 16-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 656 feet; a 14-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 502 feet; a 12-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 367 feet; a 10-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 256 feet; an eight-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 164 feet; a six-second wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) at 92 feet and so on. As noted above, longer period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) swells are affected by the ocean floor much more than short-period swells (javascript:glossarypop('surfology_glossary_index. cfm?target=short-period swells');). For that reason, we call long-period swells ground swells (generally 12 seconds or more). We call short-period swells wind swells (11 seconds or less) because they are always generated by local winds and usually can't travel more than a few hundred miles before they decay. Long-period ground swells (especially 16 seconds or greater) have the ability to wrap much more into a surf spot, sometimes 180 degrees (javascript:glossarypop('surfology_glossary_index. cfm?target=degrees');), while short-period wind swells wrap very little because they can't feel the bottom until it's too late.

<LI class=desc>Shoaling. When waves approach shallower water near shore, their lower reaches begin to drag (javascript:glossarypop('surfology_glossary_index. cfm?target=drag');) across the ocean floor, and the friction slows them down. The wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) below the surface of the ocean is pushed upward, causing the waves to increase in wave height (javascript:glossarypop('surfology_glossary_index. cfm?target=wave height');). The longer the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');), the more energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) that is under the water. This means that long-period waves will grow much more than short-period waves. A 3-foot wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) with a 10-second swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) may only grow to be a 4-foot breaking (javascript:glossarypop('surfology_glossary_index. cfm?target=breaking');) wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');), while a 3-foot wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) with a 20-second swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) can grow to be a 15-foot breaking (javascript:glossarypop('surfology_glossary_index. cfm?target=breaking');) wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) (more than five times its deep-water height depending on the ocean floor bathymetry). As the waves pass into shallower water, they become steeper and unstable as more and more energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) is pushed upward, finally to a point where the waves break in water depth at about 1.3 times the wave height (javascript:glossarypop('surfology_glossary_index. cfm?target=wave height');). A 6-foot wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) will break in about 8 feet of water. A 20-foot wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) in about 26 feet of water. A wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) traveling over a gradual sloping ocean floor will become a crumbly, slow breaking (javascript:glossarypop('surfology_glossary_index. cfm?target=breaking');) wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');). While a wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) traveling over a steep (javascript:glossarypop('surfology_glossary_index. cfm?target=steep');) ocean floor, such as a reef, will result in a faster, hollower breaking (javascript:glossarypop('surfology_glossary_index. cfm?target=breaking');) wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');). As the waves move into shallower water, the speed and the wavelength decrease (the waves get slower and move closer together), but the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');) remains the same.


Refraction. Waves focus most of their energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) toward shallower water. When a wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) drags its bottom over an uneven ocean floor, the portion of the wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) dragging over shallower water slows down while the portion wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) passing over deeper water maintains its speed. The part of the wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) over deeper water begins to wrap or bend in toward the shallower water -- much the same as how waves wrap and bend around a point like Rincon or Malibu. This process is called refraction (javascript:glossarypop('surfology_glossary_index. cfm?target=refraction');). Deep-water canyons can greatly increase the size of waves as the portion of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) moving faster over deep water (javascript:glossarypop('surfology_glossary_index. cfm?target=deep water');) bends in and converges with the portion of the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) over shallower water. This multiplies the energy (javascript:glossarypop('surfology_glossary_index. cfm?target=energy');) in that part of the wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');), causing it to grow into a larger breaking (javascript:glossarypop('surfology_glossary_index. cfm?target=breaking');) wave (javascript:glossarypop('surfology_glossary_index. cfm?target=wave');) as it nears shore. The effects of a deep-water canyon just offshore (javascript:glossarypop('surfology_glossary_index. cfm?target=offshore');) is often why we see huge waves along one stretch of beach, while maybe just a few hundred yards down the beach the waves are considerably smaller. This happens at spots such as Black's and El Porto in Southern California, and Maverick's in Northern California. Remember, the longer the swell (javascript:glossarypop('surfology_glossary_index. cfm?target=swell');) period (javascript:glossarypop('surfology_glossary_index. cfm?target=period');), the more the waves will be affected by the ocean floor bathymetry (javascript:glossarypop('surfology_glossary_index. cfm?target=bathymetry');), the more they will wrap into a spot and the more the waves will grow out of deep water (javascript:glossarypop('surfology_glossary_index. cfm?target=deep water');).
http://www.surfline.com/surfology/surfology_forecast2.cfm

[7deadlyplugs]

Thanks for posting that willie.

[skinner]

This thread has helped me to be safer out there at night. I know I definitely missed getting smashed by a few headers after I started counting them. Thank you fellas.

[DarkSkies]

^ You're welcome, skinner...:HappyWave:


Long-period Swell...

This is exactly like it sounds.
It can happen when there are storms or hurricanes in the region, but far away.
The swell from the hurricane is relayed up or down the Coast.

Because it's so far away, the surf isn't that bad...
but you will have a long period swell, where you can have wave heights of 4' or more....
The long period part of the term has to do with the duration between waves....

Generally, I consider any duration of 10 seconds or more a long period.
Others have different definitions.
This can be good for fishermen because the swell, although sometimes menacing, can give you enough time between the next wave to toss and work your artificial....


The best way to learn is not by reading it here, but going out and counting the waves yourself, and the duration. Doing this can not only make you a better fisherman, but could also save your life at night by helping you understand the degree of danger you face in fishing bigger water....

[basshunter]

The best way to learn is not by reading it here, but going out and counting the waves yourself, and the duration. Doing this can not only make you a better fisherman, but could also save your life at night by helping you understand the degree of danger you face in fishing bigger water....

Thanks dude!