Wind. I could write for hours about it. How it’s generated. Why it comes from where it does. Why it changes. What is meant by backing and veering. About its force. How it interacts with a sailboat. The differences between apparent and relative wind. Points of sail. How it interacts with and changes the surface of the water. These things and more are best very well understood by those who aim to harness wind to excitedly scoot across the surface of the water….at a breakneck speed of ….uhm……3 to 10 knots. Most of us average 6 knots. Circumnavigators (cruisers and not racers) average 3-4 knots over their entire journeys.
Recent winds in excess of 45 kn in the San Francisco Bay Area wreaked havoc in Sausalito. Boats were blown around in the anchorage. One or two were grounded. A few sank. Sails were shredded. Docks were damaged. So far, this year, unlike past years, no lives have been lost on the water as a result of these storms.
I’ve been to the docks in similar wind and winter storm conditions. It’s surprising how many boat owners do not have their boats properly secured given the forecasts. Often, docked vessels are rocking back and forth like hobby horses and sideways as if they are searching for their points of vanishing stability. It’s essential to keep ones vessel secured with both fore and aft spring lines as the wind shifts with the passing low pressures are going to come from all directions sooner or later. Winds from the south and north are not uncommon and represent a distinct change from our usual northwest winds backed to the west. Best to spring the boat all directions unless one is willing to look at wind predictions and alter lines on a daily basis.
It has been said that one can definitely distinguish wind of 5 knots by the feel of it on the face. Apparent wind may confuse the interpretation of true wind strength and direction. As one gains experience and hones observational skills direction and strength become much easier to predict while underway.
A number of different apps allow you to predict wind that may affect your sailing adventure. I have tried several of these and find that Predict Wind offers reliable predictions but the wind is oft greater than anticipated.
One may gain clues regarding wind strength from both the vessel and from outside the boat.
Here are a few thoughts or questions regarding wind assessment that can be gleaned from your sailing vessel. What are your sails doing? What do they want to do? Is the vessel turning into the wind? What is the point of sail? Is the boat heeling? Is the vessel over canvassed? Are you making progress? What is the leeway? How about the position of your flag? Burgees? Where is the masthead fly? Asking these and more questions related to what the vessel is experiencing and doing can assist in making inferences about wind. Remember that most of these observations will give you apparent wind which is always forward of true wind.
There are a lot of other indicators, both on land and at sea, that provide clues to wind direction and strength. Many of these provide a source of true wind direction and speed.
There are plenty of other way as you can deduce true wind speed and direction. Watch the clouds. While they oft show winds aloft, anything illustrating movement under 2000 feet is fairly close to what you are an example of wind direction that you are experiencing on the water. If the clouds are higher than 2000 feet just remember that the wind on the surface is backed, rotated counterclockwise, relative to what you are seeing in the sky. If you can see smokestacks billowing smoke on land they will indicate the reciprocal of the true wind direction.
Use these methods to estimate wind….and those methods familiar to you. But, mostly, learn to feel it. To sense it. To predict it from an awareness of what is going on around you with a minimum of assessments. Importantly, learn to use what you deduce about the wind to your advantage to make progress, predict trouble, stay safe, and enjoy sailing.