There is an old expression that says "Red sky at night, sailor's delight. Red sky in morning, sailors take warning." What is the origin of this expression, and what exactly is the message it is suppose to convey?

RickF

Weather systems in the UK usually move from west to east. Fronts which are usually associated with rain have high cloud with them too. As the sun rises in the east, sunlight is reflected by clouds in the west. Because of the way light bends through the atmosphere, the light will be red. This will make the clouds in the west, that are heading our way, red. A front is approaching and will usually bring rain. The opposite is true when the sun sets - it reflects off of the front that has just passed. Once a front has passed there is usually a period of calm weather before the next front approaches. Nov 29 02, 1:20 PM

Jack Flash

The saying is to be found in the New Testament. See Matthew Chapter 16 Verses 2 and 3: 'He answered and said unto them, when it is 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 lowring.' Nov 29 02, 3:40 PM

Linus

I always understood it to be shepherd's delight / shepherd's warning - same principle, different profession. Dec 01 02, 9:23 PM