Though the only person I ever knew who could come close to being described as a sailor was my great-uncle who joined the Navy at 18, my Appalachian grandmother often referenced sailors in recounting various pieces of weather lore throughout my childhood.
Of all her sayings, the one that sticks with me the most – even to this day – goes like this, “Red skies at night, sailors delight. Red skies in morning, sailors take warning.”
I was probably about seven-years-old the first time I heard her say this early one morning as the sky was bright red — eerie red. Perhaps it was the catchy ring of the rhyming saying or the fact that by the afternoon what appeared to be a beautiful day in the making had been turned to vicious storms, but whatever the reason I have never forgotten this specific of piece of weather advice.
No surprise, like so many other parts of Appalachian speech, this saying is rooted in the Scriptures. In Matthew 16, Jesus referenced this saying, stating, “When it is evening, ye say, It will be fait weather: for the sky is red. And in the morning, It will be foul weather today: for the sky is red and lowering.”
But why did this saying originate and even more importantly, is there actually any evidence that it is an accurate guide to forecasting the weather?
According to the Library of Congress, The amounts of water vapor and dust particles in the atmosphere are good indicators of weather conditions and they also determine which colors we will see in the sky.
During sunrise and sunset the sun is low in the sky, and it transmits light through the thickest part of the atmosphere. A red sky suggests an atmosphere loaded with dust and moisture particles.
When we see a red sky in the evening, this means that the setting sun is sending its light through a high concentration of dust particles. This usually indicates high pressure and stable air coming in from the west: Basically good weather will follow.
A red sunrise, however, can mean that a high pressure system (good weather) has already passed, thus indicating that a storm system (low pressure) may be moving to the east. A morning sky that is a deep, fiery red can indicate that there is high water content in the atmosphere. So, rain could be on its way.
For those in the mountains, there is also a more rural variation of this timeless rule of thumb: Red sky at night, shepherds’ delight. Red sky in the morning, shepherds’ warning.
The Truth Behind “Red Skies at Night”
