The proverb is so ancient, it can actually be found in the Bible. Even William Shakespeare can be noted using the classic “red sky” proverb with his own twist. While this saying may be over twenty centuries old, we rarely ask just how a red sky at night relates to imminent weather. This old saying has a scientific explanation that you may find interesting. The color of the sky, and its indication of the coming weather, is all about pressure systems and how "clean" the atmospheric conditions are at sunrise or sunset.
High pressure is usually associated with good weather (sailors delight), and low pressure, with bad weather (sailors take warning). As mentioned, the pressure system is only one part of the equation. The second contributing factor is the amount of particles (dust, soot and other particles) that are present in the atmosphere at the time of sunset or sunrise. According to the NOAA, atmospheric conditions in a high pressure area are typically cloud free and dirty, and those in a low pressure area are cloudy and relatively clean. We can often see red colors at sunrise or sunset due to the rays of the sun traveling through "dirty" atmospheric conditions, and resulting in a reddish hue to us earthlings. In order for the sun to light up the sky with a beautiful red shade while setting, the atmospheric conditions must be relatively clear for the setting sun in the west. A red sky at sunrise illustrates that a high pressure system has passed, only to be followed by a low pressure system which most often means rough weather and choppy seas are in the near future.
In this day and age, we are spoiled by our ability to obtain knowledge from our smart phones. Who needs an ancient proverb when you can see the radar over the entire country with two clicks of your thumb? Personally, I think we all need it. What is boating if you are constantly attached to your mobile device? Sure, there are instances when your phone may be a necessity, but as a boater, nothing is better than the tradition of the lifestyle. Watching the sky light up with magnificent colors at sunset, and thus knowing that tomorrow will be a day of great weather, is an extraordinary feeling. For a transient boater, getting to your destination safely and being able to relax as you watch the sunset from your cockpit is completely sublime.
As a 7 year old boy on Block Island, my father first explained that a red sky at night was indicative of a great day on the water to follow. As a new generation of boaters arises, in a time where we are surrounded by the newest and greatest forms of technology, it is important that we do not lose touch with boating traditions. So, take a minute to enjoy the full red sky at sunset, and get excited knowing what tomorrow will bring.