Alfred Adams, aged 10, of Salt Lake City, UT for his questions
Why is a red sky at night a sailor's delight?
Weathermen have been around for only a hundred years or so. Before that is was difficult to get up to date weather reports from distant places. The telegraph was invented in 1825. This helped speed up the weather news from place to place. This news is important in weather forecasting.
Most of our weather travels from the west. A cold spell in Kansas may freeze Chicago a week later. The weathermen gather their information from weather stations all over the world. They put this news together to forecast what is going to happen. Weather forecasting is not perfect. The weather is famous for changing its plans, even after all the facts are known. But our weathermen have a good idea of what is coming along in the wind ‑ unless the wind changes.
People tried to forecast the weather before the days of the experts and their weather stations. But most of this forecasting was pure guesswork. Some claimed to foretell the weather from animals. When a, muskrat builds an extra large house, they said, it means that a very cold winter is ahead. Some said, if it rains on Easter Sunday, then it rains for four following Sundays. This was guesswork. It may or it may not have happened.
More sensible people tried to foretell the weather from the skies. Anybody can predict a thunderstorm half an hour ahead. The huge dark clouds pile up and thunder growls and lightning flashes in the sky to announce it. Some people try to predict tomorrow's weather from the skies. People most interested in this are farmers, travelers and sailors,
Through the year, It was noticed that a bright day often came after a dull grey morning. This is reasonable. Morning comes in the eastern sky. And most of our weather comes to us from the west. If the sun rises through grey clouds, those clouds have already passed overhead. So a grey morning may very well mean that a fine day is on its way ‑ unless the weather changes its mind.
A grey sunset means cloudy skies in the west. That could mean a rainy day for us tomorrow. Red dawns and sunsets are caused by fine particles of dust in the upper air. We see these showy colors when there are not too many rain clouds to block the view.
A vivid red sunrise means that the sky is almost cloudless in the east. This fine weather has already passed over our heads. It may or may not be followed by rain during the day. But the shepherds the travelers and the sailors took warning and were prepared for rain after a red sunrise.
A red sunset means fine weather in the west. If all goes well, we can expect that fine weather to reach us by morning. That is why a red sky at night is the sailor's delight, He hopes for smooth sailing over quiet, storm less seas,