I believe the buoy Canaveral 41009 is 20 miles out.  I was curious how long it would take a 2.5 foot @ 9 seconds swell to get from the bouy to the beach, say the Cocoa Beach pier for example.  Also would there be significant difference in speed with a different size and interval swell.  I believe longer period swell travels faster but I don't know much faster.

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Heavy is sign of reliability

Typically I find it takes about 4 hours.

But it can depend on things like swell direction, period and wind.

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Replace turf grass with native plants that don't need irrigation and synthetic fertilizers or chemicals that can go into our waterways and ocean

Swell angle a factor.  My two cents is two hours.  Don't forget 41010!

 

Good question....I thought it took around 5 hours from the 120. ( 3@10 or so)

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So if you are a surfer I wish you the prosperity that allows you more time to pursue the salt water dream, and the true happiness that comes from warm water, clean waves and the companionship of your fellow surfers. If you are an internet troll just spewing bs then f off.

I remember researching this once and an average wave for us is traveling about 20 mph so about an hour from the 20 and 6 hrs from the 120 as a good guess.

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Q

I would think that swell speed would play a big role in influencing the size and power of breaking waves. A wave that is moving at 15 mph would contain a lot more volume than a wave that is moving at 10 mph even if they have the same period, right? Or do open ocean swells all travel at approximately the same speed? If this is not the reason that two swells with the same period and height can break on the beach at very different sizes, then what is the reason? And if this is the reason, then why isn't the swell speed indicated in the forecast models?
asked by Super Curious and Scared of Math

A
Surfline's very own Sean Collins responds:

The speed of travel of the deep water swell group will be 1.5 times the swell period; ie: a 20 second swell will be traveling at 30 Nautical mph. The actual individual waves will be traveling at three times the swell period, so a 20 second swell will have waves moving at up to 60 Nautical mph.

The individual waves will travel to the front of the set as the swell group moves forward; once there, it'll slow down and drift to the back of the pack before moving forward again. Think of it as a conveyor belt turning at 30mph but the whole conveyor belt chassis is actually on the back of a flatbed truck going down the highway at 30mph. So if you had an object attached to the conveyor belt -- while it's turning and being carried by the truck -- the actual speed of the object would be 60mph. (Sound like math yet?)

To learn more about the wonderful world of wave periods and energy and all that, go to Surfline's Surfology 101 -- it's free and easy.

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Dora Hates You

Great website on waves and their actions
Wave dynamics

Bottom line....
For deep water, the relationship between speed and wavelength is given by the formula:
l = g x t x t / (2 x pi)
l = t x c for all kinds of waves, substitute in above equation: t x c = g x t x t / (2 x pi)
c = g x t / (2 x pi) or t = c x 2 x pi / g or t = c x 0.641 (s)
where t= wave period (sec), f= wave frequency, l= wave length (m) and pi=3.1415...
to calculate c and l from wave period t (in sec): c = t x 1.56 m/s= t x 5.62 km/hr = t x 3.0 knot
l = 1.56 x t x t (metres)

Sorry FK, math......

Perhaps I was confusing the 120 for 4 hours?? Getting old.

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Replace turf grass with native plants that don't need irrigation and synthetic fertilizers or chemicals that can go into our waterways and ocean