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    Is the old adage “Red sky at night, sailor’s delight. Red sky in morning, sailor’s warning” true, or is it just an old wives’ tale?


    Within limits, there is truth in this saying.

Have you ever heard anyone use the proverb above?

Shakespeare did. He said something similar in his play, Venus and Adonis. “Like a red morn that ever yet betokened, Wreck to the seaman, tempest to the field, Sorrow to the shepherds, woe unto the birds, Gusts and foul flaws to herdmen and to herds.”

In the Bible, (Matthew XVI: 2-3,) Jesus said, “When in evening, ye say, it will be fair weather: For the sky is red. And in the morning, it will be foul weather today; for the sky is red and lowering.”

Weather lore has been around since people needed to predict the weather and plan their activities. Sailors and farmers relied on it to navigate ships and plant crops.

But can weather lore truly predict the weather or seasons?

Weather lore concerning the appearance of the sky, the conditions of the atmosphere, the type or movement of the clouds, and the direction of the winds may have a scientific basis and likely can predict the weather.

In order to understand why “Red sky at night, sailor’s delight. Red sky in morning, sailor’s warning” can predict the weather, we must understand more about weather and the colors in the sky.

Usually, weather moves from west to east. In the mid-latitudes, the prevailing winds are westerlies. This means storm systems generally move in from the West.

The colors we see in the sky are due to the rays of sunlight being split into colors of the spectrum as they pass through the atmosphere and ricochet off the water vapor and particles in the atmosphere. The amounts of water vapor and dust particles in the atmosphere are good indicators of weather conditions. 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. We see the red, because red wavelengths (the longest in the color spectrum) are breaking through the atmosphere. The shorter wavelengths, such as blue, are scattered and broken up.

Red sky at night, sailors delight.
When we see a red sky at night, 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.

Red sky in morning, sailor’s warning.
A red sunrise 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.

To learn more about weather lore and proverbs see the following Related Web Sites and For Further Reading sections.

Standard DisclaimerRelated Web Sites
  • Curiosities - What determines the colors of the sky at sunrise and sunset?  From the Univeristy of Wisconsin, Madison, Nov. 2007.
  • Red Sky in Morning - This page from the NOAA Earth Systems Research Laboratory looks at the science behind the saying.
  • Scientific vailidity - Joe Sienkiewicz, chief of the Ocean Applications Branch and a science and operations officer with the NOAA/NWS Ocean Prediction Center, explains the scientific validity of the saying. Scientific American.
  • Weather Forecasting Through the Ages, by Steve Graham, Claire Parkinson, and Mous Chahine - This article from the Earth Observatory at NASA discusses the history of predicting weather.
  • Weather Proverbs. Fact or Fiction? - This Web site discusses weather proverbs that, under the right circumstances, hold up to science.

Library of Congress Web SiteFurther Reading
  • Allaby, Michael. Weather lore. In Encyclopedia of weather and climate, vol. 2. New York, Facts on File, c2002. p. 625-636.
  • Christian, Spencer, and Antonia Felix. Can it really rain frogs? The world’s strangest weather events. New York, Wiley, 1997. 121 p. (Juvenile).
  • Dolan, Edward F. The Old farmer’s almanac of weather lore: the fact and fancy behind weather predictions, superstitions, old-time sayings, and traditions. Dublin, N.H., Yankee Books, c1988. 224 p.
  • Forrester, Frank H. Weather lore- Facts and fancies. In 1001 questions answered about the weather. New York, Dover, 1981. p. 278-291.
  • Freier, G.D. Weather proverbs: how 600 proverbs, sayings, and poems accurately explain our weather. Tucson, AZ, Fisher Books, c1992. 214 p.
  • Garriott, Edward B. Weather folk-lore and local weather signs. Washington, Gov't Printing Office, 1903. 153 p.
    Available online:
  • Lee, Albert. Weather wisdom: being an illustrated practical volume wherein is contained unique compilation and analysis of the facts and folklore of natural weather prediction. Garden City, NY, Doubleday, 1976. 180 p.
  • Weather wisdom: proverbs, superstitions, and signs. New York, Peter Lang, c1996. 478 p.

SearchFor more print resources...
Search on "Weather folklore," "Weather lore," "meteorology" or "climatology" in the Library of Congress Online Catalog.

Photo: Red sunrise
Sunrise NOAA Photo Library

Photo: Red sunset
Sunset highlighting dense cirrus clouds NOAA Photo Library.

Amur Bay, training ship Nadezhda, Vladivostok, Russia
Amur Bay, training ship "Nadezhda", Vladivostok, Russia Prints & Photographs Division, Library of Congress.

Photo:  African American man, Charles Batties(?), full-length portrait standing, facing front, wearing sailor uniform.
Photo: African American man, Charles Batties(?), wearing sailor uniform. Prints & Photographs Division, Library of Congress. Also see: African American Odyssey: The Civil War

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 September 27, 2018
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