RED SKY IN THE MORNING, SAILORS TAKE WARNING & RED SKY AT NIGHT, SAILORS DELIGHT: Is this folklore true? The concept is over two thousand years old and is cited in the New Testament. The rhyme has become a rule of thumb, used for weather forecasting on the seas, during the past two millennia. It is based on the reddish glow of the morning or evening sky, for mariners to prepare for what's to come that day... and Meteorologist Brittney Merlot says the concept is mostly true! Here's why...
During sunrise and sunset the sun is low in the sky, and it transmits light through the thickest part of the atmosphere. Red is the longest wavelength in the spectrum and can reach an atmosphere loaded with dust and moisture particles. Once it hits that, red light is reflected back to us and we see a red sky.
When we see a red sky in the evening, this means that the setting sun in the west is sending its light through a high concentration of dust particles to the east. This indicates a low pressure storm system is departing the area, while a high pressure system is arriving and stable air coming in from the west: meaning good weather will follow.
A red sunrise, indicates that a low pressure storm system is moving in from the west. This is as the sun rises in the east and hits high water content off to the west. A morning sky that is a deep, fiery red can indicate that there is heavy rain and high winds on its way.
In the video above 👆 Meteorologist Brittney Merlot breaks it down for you and explains how the prevailing winds are the main reason why this is true.