Though Weather Radio is a great way to know exactly what is going on, and NOAA and the NWS have worked hard to provide accurate information, predictions are not always correct, and reliance on electronics as your only source of understanding the weather can be dangerous. As you become an experienced boater, you learn that there are many signs that will help you get an idea of what kind of weather is approaching. Some are based on folklore, but many have proven to have some truth to them. Here are some of the different things to watch for, and what they may mean.
One of the first tricks a boater should learn is how to read clouds. The shape of a cloud, its speed, and its position in the sky are all hints as to what the weather will be doing in the near future. This article on reading clouds is a great introduction to what to watch for. Here are a few additional tips on cloud reading:
Celestial objects like the sun, moon, and stars are beautiful to look at. They also have a great ability to highlight moisture in the air that cannot be seen by the naked eye. This feature makes them excellent weather predictors. There is an old rhyme that says: “Ring around the moon, rain before noon. Ring around the sun, rain before the day is done.” Whether the air is cloudy, hazy, or clear, these rings are a reflection on moisture-laden ice crystals in the atmosphere. Large rings are called haloes, and small rings are called either lunar or solar coronas. The tighter the ring is to the edge of the celestial body, the more time you have before a rain. Large, loose rings are more predictive of rain within a few hours or less. The strength of the ring is often correlated to the strength of the coming rain. If you can count a number of stars between the edge of the halo and the moon, then there is not enough humidity for a large rain event, and will likely mist or sprinkle instead. Wind events can also be seen in a halo — twinkling stars suggest quick-moving crystals. Approaching winds and double haloes are often heralds of stormy weather as well. It is important not to confuse a halo with something termed a “fire bow.” This is a section of cirrus clouds that is lit up like a rainbow near or because of the light from the sun. These most often occur when the sun is low on the horizon. The clouds that are reflecting like a rainbow are not precipitating, but are ice crystals acting as a prism.
Pressure is a huge predictor in upcoming weather. As a general rule, nice weather is in an area with high pressure, and stormy weather is in an area with low pressure. Air always wants to go from a high-pressure area to a low-pressure area, and because of this, regions that sit between high and low pressure regions are often very windy. The tool that boaters and other weather predictors use to monitor this pressure change is called a barometer. This handy tool can tell you several things. As pressure increases, the weather will become nicer. As pressure decreases, weather will often become rainier. The faster that this change happens, the more winds will likely accompany the change.
Pressure changes can also be felt, to some extent. Anyone who has had a broken bone or arthritis knows the feeling of aching bones before a change in the weather. This is due to the fact that the drop/gain in pressure outside the bone is different than what is inside the bone. This creates pain, which, though annoying, is a wonderful weather gauge.
Animals often act differently as the weather changes as well. If you boat with pets, keep an eye out for unusual behavior. As you learn your own animal’s impending weather signs, they can also become valuable storm spotters. Even if you are boating pet-free, there are a number of animal signs to watch for on the ocean itself. Again, be ready for unusual behavior, as it could be a sign of an impending storm. Here are some other common signs that something might be changing:
The key to any good boating experience is to stay observant of the world around you. As you make sense of your environment, you will likely be able to develop your own sense of what weather predictors work best for you in your specific area. Keep a journal of observations and resulting weather to test your ideas. It is also important to remember to stay safe during any bad weather by simply avoiding it, seeking shelter, or preparing your boat for safe passage.