For centuries people whose lives depended on the weather have relied on Folklore to tell them what to expect. Farmers and sailors in particular developed a keen sense of observation and began to connect changes in nature with the patterns and rhythms of the weather. Cloud movement, wind shifts, sky colour, wave motion and even the behaviour of insects and animals, became indicators, which they learned to interpret to guide them in their planning. Many of these signs were remembered in the form of short sayings or rhymes to make them easier to recall, but only those that have passed the test of scientific investigation and careful observation have become reliable guides to weather change. Here are some examples of well-known weather proverbs, which may actually give fairly accurate forecasting for sailors and navigators.
“Red sky at night – shepherds delight
Red sky in the morning – shepherds warning”
Weather systems normally move from west to east, and clouds appear red when the sun shines on their undersides at sunrise or sunset. At these times the sun’s rays are passing through the atmosphere at a very low angle, scattering out the shorter wavelengths of the spectrum which are the greens, blues and violets, and leaving the red colours. If the sky is red in the morning it is because clear skies to the east are letting the sun light up the undersides of moisture bearing clouds coming from the west. On the other hand, if there are red clouds in the evening, the sunlight must have a clear path from the west in order to light up the moisture-bearing clouds moving off to the east. This proverb is even quoted in the bible – Matthew 16:2-3 where Jesus is talking to some Pharisees and Sadducees about signs from heaven.
“When halo rings the moon or sun, rain’s approaching on the run”
A halo round the sun or the moon is caused by high altitude ice crystals refracting their light. This high level moisture is a forerunner of moisture approaching at lower levels, and is a good indicator that an active weather system is on its way. Halos usually develop into “milky sky” when the sky is clear but looks washed-out and not its typical blue colour. This very high cirrostratus cloud is an indicator of an approaching low system.
Sun dogs
Some halos are often referred to as “sun dogs” or a “mock sun”, which may appear as coloured patches of light on either side of the sun, usually at sunset or sunrise. Often the sun dog is just a small area shining brightly in high level cloud, but as the cloud thickens it will become duller and disappear. They can be seen anywhere in the world, and are most conspicuous when the sun is low in the sky, and are indicators of the arrival of a warm front. The yachtsman can expect increasing and backing winds, and as the front gets nearer he should prepare for rain and decreasing visibility.
“A cow with its tail to the West makes the weather best
A cow with its tail to the East makes the weather least”
Cows normally prefer to stand with their backs to the wind and since westerly winds are usually the precursors of fine weather, and easterlies usually signify unsettled weather, a live “cow-vane” is a pretty good indicator of what the weather is going to do in the next few hours. So watch the cows if you are sailing close to the coast. The rhyme “When the wind is out of the east, ‘tis neither good for man nor beast” has the same warning.
“In the morning, mountains, in the afternoon, fountains”
Clouds which have been building up through the morning to look like mountains are often followed by thunderstorms in the afternoon. As the sun heats the ground during the morning, small cumulus clouds appear which can rapidly grow into huge mountain-like clouds. By afternoon these will have reached the top of the atmosphere, producing rain and lightning below.
“Mackerel scales and mare’s tails make lofty ships carry low sails”
and “Mackerel sky, mackerel sky, never long wet, never long dry”.
This refers to altocumulus and cirrus clouds, high-level ice clouds foretelling an approaching front. The mare’s tails are the cirrus clouds, shaped by the upper winds to resemble the flowing tail of a horse. The mackerel scales are the altocumulus which is influenced by the shifting wind directions and high speeds, and appear broken and scaly. Neither is directly responsible for bringing rain or snow, but they do usually precede an approaching front, so sailors should expect increased winds and rougher seas. The “never long wet, never long dry” refers to the westerly winds associated with mackerel skies, which blow frontal systems rapidly from west to east, so the rain bands usually do not last for more than a few hours. Mackerel skies following a cold front indicate an unstable atmosphere which equals showers. They may not form instantly but are likely to appear before long.
“When the wind backs and the weather glass falls, prepare yourself for gales and squalls”
A backing wind is one which changes direction in an anticlockwise manner, often starting in the west and then changing through southwest, south and then southeast. A backing wind usually indicates the approach of a low pressure system from the southwest. The “weather glass” refers to an early barometer. When it falls, it indicates lowering of atmospheric pressure, warning of an approaching storm system. A similar rhyme appropriate for sailors reads, “When the glass falls low, prepare for a blow; when it rises high, let all your kites fly”.
“If clouds move against the wind, rain will follow”
Clouds that are moving in a different direction from the wind create a condition known as wind shear. This often indicates the arrival of a cold front which will probably bring rain.
“If woolly fleeces bestow the heavenly way, be sure no rain will come today”
Scattered cumulus clouds looking like fluffy sheep are a sign of settled weather and are often known as “fair weather clouds.
These well-known sayings are perhaps not a reliable substitute for the good old weather forecast. On the other hand, you might have forgotten to tune in to the shipping forecast at 5am, and they only relate to the conditions in your immediate locality, not many miles away. Finally, I must admit I do admire people who glance up at the sky and then tell me what the weather will do, even if they are making it up. I remember a very good farmer friend of mine surveying the sky and forecasting the forthcoming weather very knowledgably. “How can you tell that?” I asked. “Oh I listened to the weather forecast this morning”, was the reply.
Author – Dee White