The wind "feeds" sailboats during the movement, so any yachtsman, whether a beginner on a chartered yacht, or an experienced yachtsman on good a yacht that is familiar to him, should always be interested in the direction of the wind and its speed. Many people think about the question even before leaving the marina: "Will the wind change?"
It is difficult to give a precise definition of "wind strength". Almost all captains with extensive experience behind their shoulders cannot correctly recognize "by eye" the strength of the wind. Sometimes, relying on the number of raised sails, helping the yacht's movement, experienced captains are able to almost accurately determine the strength of the wind on the Beaufort scale up to 7 points. The Beaufort scale is a conventional scale (12-point), which allows you to visually determine the strength and speed of the wind from the waves of the water surface, officially adopted in 1838. The scale was developed in 1806 by the military admiral Francis Beaufort, who, while serving in the navy, regularly observed the wind and recorded the data in a diary.
Yachtsmen are more likely to consider the magnitude of the wind force to be greater than the actual value due to sudden gusts bursting into a uniform air flow. It is believed that wind pressure is directly proportional to the square of its speed. The wind gust (with an approximate force of up to 40 knots) is quite noticeable, from the ship's heel angle, increasing 16 times. The attention of yachtsmen is usually directed to squally wind gusts, which create a dangerous list of the yacht. The sails are simply obliged (and the masts also need) to withstand such a sharp sudden wind.
On a sea voyage, it is absolutely impossible to foresee everything and the weather can bring unexpected surprises. For example, just one swift wind gust of 64 knots can easily turn a yacht, or even break the mast. Unexpected 6-point wind gusts are much more dangerous than a uniform 7-point wind, as they form "incomprehensible" waves.
Very rarely, but there are such anomalous phenomena as the formation of waves up to 30 meters high with a wind force of 6-7 points. Typically, these waves correspond to a 10-point storm in the ocean! Scientists have put forward versions that such waves can occur due to different directions of currents, the presence of shoals, changes in the direction of the wind, etc. A scientific explanation is difficult to find, and sailors call them "abnormal" or "wrong" waves. It couldn't be better!
The Beaufort scale is usually used to determine the average (not maximum) wind strength. Correctly formulated characteristic sounds like this: “storm wind with gusts of up to 50 knots”, not “storm wind of 10 points”. If wind gusts continue for a long time, then in a 10-point storm, their value increases to 64 knots.
In the Sailing Ships magazine, Alan Watts provides guidelines for the definition of "average yachting wind". It is required to add Beaufort wind strength to the average wind speed and determine the average value. For example, the gale force of the wind is 25-30 knots with regular gusts of wind up to 40 knots at intervals of 5-10 minutes.
Many people prefer to use Beaufort averages, especially since meteorologists use this system to predict weather conditions and storms for all shipping. This information is relevant for both large ships and small-size fleets. In some areas, storm winds behave differently. There is a possibility that two yachts within 30 miles of each other will be subjected to completely different tests when caught in a storm. For example, one of them will avoid a heavy wind.
Amateur yachtsmen, as well as "sea wolves" tend to increase the height of the waves, because they correlate them with the height of the mast, the value of which is known for sure. Any crew member is capable of calculating wind strength in this way, but this estimate is biased. In fact, when windy, the wave height is always less visible. As a rule, the actual height of the waves in relation to the visual one is 3/5 or even less. Oceanographers confidently declare that it is impossible to determine the height of the waves with the help of an eye.
So, a more or less accurate determination of the wind strength can only be obtained with the help of meteorologists, because they are guided by the data of special instruments.
During an ordinary storm, there are high waves (up to 8 meters) and up to 150 meters long. In case of a strong storm, the wavelength is up to 200 meters, and the height is 9-11 meters. As noted by experienced yachtsmen 2yachts, it happened more than once that the appearance of a stormy wind did not cause a real storm in the proposed area, therefore a specific yacht located in the area warnings, the wind may bypass. At sea, it is difficult to make accurate forecasts of weather conditions.