The Meaning of Mackerel Clouds

The Meaning of Mackerel Clouds

The science behind the farmer’s and sailor’s maxims

Weather folklore has been passed down through the ages by mariners and farmers who relied on their own observations of astronomical events, animal behaviors, and atmospheric changes to predict upcoming weather events.

Today, while the average person’s ability to observe the natural world has declined, much of the folklore still exists, partly because of a psychological yearning to keep in touch with a time when humans seemed more in tune with their environment. Here we help discern what of today’s remaining weather lore is still viable: Red sky at night, sailors delight.

Red sky in the morning, sailor take warning: Much of the weather folklore based on observations of atmospheric phenomena is a fairly good predictor of short-range weather changes. In the mid-latitude regions, the general flow of storm systems follows the jet stream from west to east. The red color at night is due to the reflection of the red colors from the sun as it lowers in the western sky. This signals that the jet stream has pushed the storm systems out of your area. If clouds appear red in the morning, this means that the sun is rising in clear skies to the east with clouds approaching from the west, indicating the storm system is to your west and moving your way.

Roseraie. Photo: Elena

Mackarel clouds in the sky, expect more wet than dry: This is another good example of accurate weather folklore based on atmospheric observations. Mackerel clouds refer to cirrocumulus clouds that appear pearly white with scaly formations akin to the scales on a fish, Ancient mariners knew that these clouds presaged the approach of a warm front that would produce rain or snow within the next 12 to 18 hours.

When round the moon there is a halo, the weather will be cold and rough: The halo is generated by cirrostratus clouds 15,000 to 20,000 feet up in the atmosphere. These clouds cover great areas with a uniform thickness of ice crystals, which are responsible for many optical wonders. A halo around the moon generally means stormy weather within the next 24 hours.

When smoke hangs low, a storm is approaching: Meteorologists attribute the phenomenon of smoke hanging low to low pressure systems that cause the atmosphere to be unstable and can signal the approach of stormy weather. However, sometimes near lakes, and in valleys, local air circulation can dominate the larger scale circulation that can give a false reading.

When hornets build their nest close to the ground, expect a hard winter: Folklore that deals with animals and long-term weather forecasts generally is false. Meteorologists believe that if people observed the hornet’s activities over a long period of time, they would find no correlation between the hornet’s behaviour and seasonal forecasts. The same is true for folklore that links a squirrel’s very bushy tail or a large black band on a woolly-bear caterpillar with an upcoming severe winter. 

If bees stay at home, rain will soon come: We can liken this folklore to similar and associate approaching storms with hornets lining up to go back to their nest, cows lying down in a field, frogs singing more than usual. Scientists admit that these examples are difficult to prove or disprove, because scientists can’t isolate what in the environment would be causing these behaviours. However, we would have to err on the side of bee keepers who swear by the ability of their bees to predict rain. With cows, though, we can jokingly ask, “if 25 cows are lying down in a field, and 25 are standing up, does that mean there’s a fifty percent chance of rain?”

Crickets are a poor man’s thermometer: Counting the chirps of a cricket, is an accurate way of determining temperatures above 40 degrees Fahrenheit. Below 40 degrees, a cricket’s metabolism is too slow. To get the current air temperature within one degree Fahrenheit, count the number of chirps in a 14-second period and then add 40 this number.

Pins Victoria Park. Weather folklore has been passed down through the ages… Photo: Elena

The air smells sweet before a storm: Science definitely has an explanation for this folklore. Before a storm, lower pressure predominates, which causes plants’ stomatic openings to enlarge and emit more gases, including ones that are aromatic.

When human hair becomes limp, rain is near: Human hair – especially blond hair – becomes thicker and longer when exposed to increases in humidity, which sometimes mean rain is near. In fact, early hygrometers designed to determine the moisture content of the air relied on measuring the changes in the length of a human hair.

Sinus and joint pain signals story weather: This folklore, at least for arthritis sufferers, has been proved to signal rapid changes in the weather. Pressure changes , the cause of the pain, signal the unstable atmospheric conditions that typically precede a storm.