water sailor I've wondered how, on large open waters, you measure wave heigth. Trough to crest, mid-trough to top, etc. Also swell heigth, and is this included with wave heigth? Fairly basic stuff for some, but so is plow depth when farming. Thanks, Ray S/V Speedy
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A wave height is measured...
At the wave back from the peak to the base of the trough (although most people observe the face). Most shipboard weather observers (which I was in the Navy) take about three to four minutes and observe the waves to try to obtain the "significant (heighest 1/3 of the average wave height) wave height." The bottom line...a human observed wave height is usually an estimated wild A$$ guess. For the heights MOST sailors will see they are generally accurate to 1-2 feet, but experience plays a large part.
At the wave back from the peak to the base of the trough (although most people observe the face). Most shipboard weather observers (which I was in the Navy) take about three to four minutes and observe the waves to try to obtain the "significant (heighest 1/3 of the average wave height) wave height." The bottom line...a human observed wave height is usually an estimated wild A$$ guess. For the heights MOST sailors will see they are generally accurate to 1-2 feet, but experience plays a large part.
Depends who's asking
Ray, Being a bit of a country boy myself and at the same time also being a coastal sailor, I feel I am uniquely qualified to explain this to you. For most sailors we look at the trough, crest, and maybe the free board, and make an experienced, educated guess. Just like you country farm boys can tell how much a bear weighs just by looking at him. Just like bear stories, the weight will be effected by who we're telling and how long we've been sitting in the cockpit sipping our favorite grog.
Don
Ray, Being a bit of a country boy myself and at the same time also being a coastal sailor, I feel I am uniquely qualified to explain this to you. For most sailors we look at the trough, crest, and maybe the free board, and make an experienced, educated guess. Just like you country farm boys can tell how much a bear weighs just by looking at him. Just like bear stories, the weight will be effected by who we're telling and how long we've been sitting in the cockpit sipping our favorite grog.
Donmeasuring wave height
I am not sure if you are looking for a hi tech or just a every day quick guess on how to measure wave height. the average person just kind of make a rough guess by looking. However if you get hi tech the weather service uses all sort of ways including weather bouys that can measure the waves and caluclate height.
I am not sure if you are looking for a hi tech or just a every day quick guess on how to measure wave height. the average person just kind of make a rough guess by looking. However if you get hi tech the weather service uses all sort of ways including weather bouys that can measure the waves and caluclate height.
Don, A bears weight can only be calculated by
the size of the pile found in the woods, thus answering your next question. Ray S/V Speedy
the size of the pile found in the woods, thus answering your next question. Ray S/V Speedy
Marine bouy readings give wave charactersitics
Try this website: http://www.marineweather.com/Frame247DialaBouy.html --Ron
Try this website: http://www.marineweather.com/Frame247DialaBouy.html --Ron
WATCH - LISTEN!
I've probably sailed in waves up to and including 6-8 footers. I listen to the marine weather and the Coast Guard weather updates and let THEM tell me how high the waves are. Bill on STARGAZER
I've probably sailed in waves up to and including 6-8 footers. I listen to the marine weather and the Coast Guard weather updates and let THEM tell me how high the waves are. Bill on STARGAZER
NWS - NOAA- Wilmington NC station says....
Since I have gotten so many different answers from so many different sources including the coast guard, I visited the folks who make the reports. These folks tell me that they report the average trough to crest height of the tallest third of the waves. The problem is that the report is and average for up to twenty miles offshore and in that area conditions will very a lot. The winds are reported as the average of a two minute reading. Gusts are sometimes reported separately.
Since I have gotten so many different answers from so many different sources including the coast guard, I visited the folks who make the reports. These folks tell me that they report the average trough to crest height of the tallest third of the waves. The problem is that the report is and average for up to twenty miles offshore and in that area conditions will very a lot. The winds are reported as the average of a two minute reading. Gusts are sometimes reported separately.
NOAA
We were coming home from Martha's Vineyard last year through some pretty big waves. I checked the NOAA historical data for that date and it said 9ft swells. I thought they were bigger so I called NOAA and got some interesting info. I told the guy they seemed bigger than 9ft. He said you have to add the average swell height to the average wave height. Swells and waves are different! The waves that day were 2ft to 4ft. So we were in 11 to 13 footers. That sounded more like what I saw. Swells are generally tidal, waves are wind driven. Anyway those were averages, I know I went over a few 15 or 16 footers. What a ride! Regards, Chris
We were coming home from Martha's Vineyard last year through some pretty big waves. I checked the NOAA historical data for that date and it said 9ft swells. I thought they were bigger so I called NOAA and got some interesting info. I told the guy they seemed bigger than 9ft. He said you have to add the average swell height to the average wave height. Swells and waves are different! The waves that day were 2ft to 4ft. So we were in 11 to 13 footers. That sounded more like what I saw. Swells are generally tidal, waves are wind driven. Anyway those were averages, I know I went over a few 15 or 16 footers. What a ride! Regards, Chris
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