- Oct 22, 2014
- 22,753
We have talked about wind and weather mostly about managing our exposure and avoiding dangerous sailing conditions.
I got to thinking, for the experienced among us, we talk about reefing when the wind picks up. That is a nebulous statement. How do we know that the “Wind” has picked up? Not everyone has electronic gear to tell us “this breeze is 10 knots... let some sail out.“ Or “ it is getting 18-20 knots. Perhaps the heeling is getting too much in the gusts - better ad a reef and reduce the jib”
Without all these electronic aides how did sailors survive. How did they know it might be time to alter the sail plan by shrinking “Reefing” the sails.
We have Sir Francis Beaufort to thank for the invention of the Beaufort Scale. Being an Irish hydrographer, Beaufort developed a scale based upon wind and sea observations while serving in the Royal Navy. The scale gives sailors a common tool to base their wind and sea observations when sharing weather information.
Beaufort Wind Scale
Developed in 1805 by Sir Francis Beaufort, U.K. Royal Navy
Sailing in a variety of wind and sea conditions, and observing/recording the observations, you can develop a reliable tool to aide your sailing. You can check your observations with the weather reports to help improve your ability as a weather observer.
How do you do this? Well get out on the water and raise your sails. It looks like a beautiful day. A you power out of the slip you gaze at the water and see wavelets covering the bay. You feel the breeze on your cheek you raise your sails and your boat responds, moving at an enjoyable speed. Maybe a little heel and some of the wavelets (say 20%) have white wave caps.
Checking the Beaufort scale you determine maybe a 2 or a 3 force Light /Gentle breeze. The Beaufort scale is not an exact nor an objective scale; it was based on visual and subjective observation of the sea. So you look up the weather condition on your cell phone weather app. It reports the wind at 5 to 8 knots.
This is a time for a sail and a
.
So your next day you head for the boat, you see that the flags in the marina are whipping straight out. You get excited about the possibility sailing. Looking out at the water, beyond the break water, you see waves.. They break on the break water. 75% of the waves in the bay have "White tops" and some are breaking with spray. What would Beaufort say abut this? Well maybe this is a Moderate or even a Fresh Breeze. It is very tempting. So I am going to follow the advise on SBO and rig the boat with reefs. I'll start with a single reef on the main and because I have roller reefing when I open the fore sail I'll start with maybe only 50% of the sail.
We go out and have a great time. There were a few gusts and the boat would heel. A couple of times you get that scary feeling in your stomach, but your boat settles and your feeling pretty good about your sailing abilities.
Checking our trusty weather app, we see the experts telling us the winds are 14 to 18knots. with gusts to 20. Force 4-5 on the Beaufort scale.
I was watching a Norwegian sailor who videoed his experience sailing in a Force 10 gale. Here is his shared experience.
I hope you soon get the opportunity to test your wind and sea observation skills.
I got to thinking, for the experienced among us, we talk about reefing when the wind picks up. That is a nebulous statement. How do we know that the “Wind” has picked up? Not everyone has electronic gear to tell us “this breeze is 10 knots... let some sail out.“ Or “ it is getting 18-20 knots. Perhaps the heeling is getting too much in the gusts - better ad a reef and reduce the jib”
Without all these electronic aides how did sailors survive. How did they know it might be time to alter the sail plan by shrinking “Reefing” the sails.
We have Sir Francis Beaufort to thank for the invention of the Beaufort Scale. Being an Irish hydrographer, Beaufort developed a scale based upon wind and sea observations while serving in the Royal Navy. The scale gives sailors a common tool to base their wind and sea observations when sharing weather information.
Beaufort Wind Scale
Developed in 1805 by Sir Francis Beaufort, U.K. Royal Navy
Force | Wind (Knots) | WMO Classification | Appearance of Wind Effects | |
|---|---|---|---|---|
| | On the Water | On Land | |
0 | Less than 1 | Calm | Sea surface smooth and mirror-like | Calm, smoke rises vertically |
1 | 1-3 | Light Air | Scaly ripples, no foam crests | Smoke drift indicates wind direction, still wind vanes |
2 | 4-6 | Light Breeze | Small wavelets, crests glassy, no breaking | Wind felt on face, leaves rustle, vanes begin to move |
3 | 7-10 | Gentle Breeze | Large wavelets, crests begin to break, scattered whitecaps | Leaves and small twigs constantly moving, light flags extended |
4 | 11-16 | Moderate Breeze | Small waves 1-4 ft. becoming longer, numerous whitecaps | Dust, leaves, and loose paper lifted, small tree branches move |
5 | 17-21 | Fresh Breeze | Moderate waves 4-8 ft taking longer form, many whitecaps, some spray | Small trees in leaf begin to sway |
6 | 22-27 | Strong Breeze | Larger waves 8-13 ft, whitecaps common, more spray | Larger tree branches moving, whistling in wires |
7 | 28-33 | Near Gale | Sea heaps up, waves 13-19 ft, white foam streaks off breakers | Whole trees moving, resistance felt walking against wind |
8 | 34-40 | Gale | Moderately high (18-25 ft) waves of greater length, edges of crests begin to break into spindrift, foam blown in streaks | Twigs breaking off trees, generally impedes progress |
9 | 41-47 | Strong Gale | High waves (23-32 ft), sea begins to roll, dense streaks of foam, spray may reduce visibility | Slight structural damage occurs, slate blows off roofs |
10 | 48-55 | Storm | Very high waves (29-41 ft) with overhanging crests, sea white with densely blown foam, heavy rolling, lowered visibility | Seldom experienced on land, trees broken or uprooted, "considerable structural damage" |
11 | 56-63 | Violent Storm | Exceptionally high (37-52 ft) waves, foam patches cover sea, visibility more reduced | |
12 | 64+ | Hurricane | Air filled with foam, waves over 45 ft, sea completely white with driving spray, visibility greatly reduced |
Sailing in a variety of wind and sea conditions, and observing/recording the observations, you can develop a reliable tool to aide your sailing. You can check your observations with the weather reports to help improve your ability as a weather observer.
How do you do this? Well get out on the water and raise your sails. It looks like a beautiful day. A you power out of the slip you gaze at the water and see wavelets covering the bay. You feel the breeze on your cheek you raise your sails and your boat responds, moving at an enjoyable speed. Maybe a little heel and some of the wavelets (say 20%) have white wave caps.
Checking the Beaufort scale you determine maybe a 2 or a 3 force Light /Gentle breeze. The Beaufort scale is not an exact nor an objective scale; it was based on visual and subjective observation of the sea. So you look up the weather condition on your cell phone weather app. It reports the wind at 5 to 8 knots.
This is a time for a sail and a
.So your next day you head for the boat, you see that the flags in the marina are whipping straight out. You get excited about the possibility sailing. Looking out at the water, beyond the break water, you see waves.. They break on the break water. 75% of the waves in the bay have "White tops" and some are breaking with spray. What would Beaufort say abut this? Well maybe this is a Moderate or even a Fresh Breeze. It is very tempting. So I am going to follow the advise on SBO and rig the boat with reefs. I'll start with a single reef on the main and because I have roller reefing when I open the fore sail I'll start with maybe only 50% of the sail.
We go out and have a great time. There were a few gusts and the boat would heel. A couple of times you get that scary feeling in your stomach, but your boat settles and your feeling pretty good about your sailing abilities.
Checking our trusty weather app, we see the experts telling us the winds are 14 to 18knots. with gusts to 20. Force 4-5 on the Beaufort scale.
I was watching a Norwegian sailor who videoed his experience sailing in a Force 10 gale. Here is his shared experience.
I hope you soon get the opportunity to test your wind and sea observation skills.
