Because of the smog in the atmosphere, the sky over Los Angeles is often reddish both at night and in the morning. Last time, I checked the ships were moving in and out of San Pedro Harbor just fine. But, that’s not to say there’s no truth to the “Red Sky at Night, Sailor’s Delight; Red Sky at Morning, Sailor take Warning,” saying. It especially holds true in the United States where the storm track is from west to east.
Our earth is covered with alternating high pressure and low pressure areas. If you have an area of low pressure, you automatically have high pressure on either side. Low pressure means bad weather and high pressure means nice sailing. Low pressure causes air to converge to fill the low and all that air coming together creates upward motion that turns into clouds and precipitation. The opposite is a high pressure area which pushes moist air away causing downward motion.
At sunset when the sun is just setting in the west the spectrum of sunlight aims toward the east. Red light is the longest and if it encounters moisture or dirt-filled clouds, the sky turns red. That’s good news to the sailor because it means the low pressure is already to the east and high pressure will follow from the west. In the morning, the opposite is true. The sun rises in the east. If the sunlight beamed toward the west encounters clouds, the sky turns red. With a storm track from west to east, the bad weather will be coming right at our fictional sailor.
There are many, many reasons that can make the red sky warning false. On the east coast, storms often swirl in from a south east direction rather then from the west. Volcanic ash, dust, or other contaminants can also reflect sunlight and turn the sky red. Anyone who has flown into a smog-filled city knows that the atmosphere is a permanent reddish-brown.
Weather sayings are fun and there is usually some truth to them. I particularly like the ones about animals.
If a cat washes her face o’er her ear, tis a sign the weather will be fine and clear.
Cat fur builds up static electricity when it’s dry; the cat moistens its fur to prevent shocks.
If birds fly low, Expect rain and a blow.
It’s easier for birds to fly at a higher altitude when air pressure is high.
If the rooster crows on going to bed, You may rise with a watery head.
Animals react negatively to decreased atmospheric pressure. They become restless. Restless roosters crow. Decreased atmospheric pressure may be what makes a dog agitated long before thunder is heard. They sense the approaching storm.
Rainbows are also warnings of storms.
Rainbow in the morning, Shepherds take warning. Rainbow at night, Shepherd’s delight.
Rainbows occur in the part of the sky opposite the sun. Light refracts through water droplets into its prism of colors. In the morning, the sun is in the east so the rainbow would be in the west coming straight at us. If the evening, the sun would be in the west, so a rainbow in the east would mean the storm is past.
Man has invented all sorts of equipment from simple weather vanes to fancy barometers and anemometers to help him predict the weather. Imagine the increased tragedy hundreds of years ago when storms like tornadoes, hurricanes, and typhoons were a total surprise. They’re still devastating even with the advance warning provided by our modern equipment, but at least people do have a better chance to take shelter.
One of the best weather predictors may be the human body.
A coming storm your shooting corns presage, And aches will throb, your hollow tooth will rage.
My brother’s roommate at UCLA was a meteorology student. Every year there was a weather predicting contest in which students turned in their predictions every day for a term. The winner? The janitor who slipped his predictions into the box. He had “rheumatism” and it proved to be a more accurate predictor of pressure change than anything manmade. I’m wondering if he looked at the color of the sky, too.
