NATIONAL MARITIME HISTORICAL SOCIETY

Whether it’s cold or whether it’s hot;
We shall have weather, whether or not!

Long before we had satellites and weather radar, websites, TV forecasters, and smart phones to tell us what the weather is going to be the next day, people have been predicting the weather by studying what’s happening in the sky. How the clouds are changing and where the wind direction is shifting can tell you a lot about what’s to come if you know a few things about meteorology.

If there is anyone who needs to be adept at predicting the weather, it would be the mariner. Out at sea, changes in weather mean changes in sea conditions, wind strength and direction, and the sailor who does not pay attention to the signs might find him- or herself in a very dangerous situation.

To remember what to look for and what the signs mean, people made rhymes to help them. Some expressions about weather have come down through the ages, but do any of them work? Let’s take a look at some of the most common.

 

Red sky at night, sailors delight. Red sky in morning, sailors take warning.

This is likely the most well-known of all weather lore. Way back in 1593, William Shakespeare wrote about it in his poem “Venus and Adonis”—

Like a red morn, that ever yet betoken’d
Wreck to the seaman, tempest to the field,
Sorrow to shepherds, woe unto the birds,
Gusts and foul flaws to herdmen and to herds.

So, was Shakespeare telling the truth? In fact he was! We see colors in the sky when rays of sunlight split into the different colors of the spectrum as they pass through the earth’s atmosphere. A high pressure system will trap dust and vapor in the atmosphere, scattering the blue light and leaving only the red. High pressure systems are generally associated with good weather.

In the US, most weather systems move from west to east. When the sun is in the west at sunset, a red sky indicates that a high pressure system is moving in from the west, bringing good weather with it. A red sky at sunrise, however, shows that the high pressure system has already passed to the east and away from the observer. A low pressure system will follow, bringing with it bad weather.

 

Mares’ tails and mackerel scales make tall ships carry low sails.

True or False?

True! “Mares’ tails” are high cirrus clouds that have been shaped by strong winds in the upper atmosphere and often signal an advancing front. “Mackerel scales” are cirrocumulus clouds—cloud formations that look like fish scales in the sky. Cirrocumulus clouds often form ahead of a warm front. The approaching front will cause the wind direction to shift and ultimately brings rain and high winds to the region.

 

If there is a halo round the sun or moon, then we can expect rain quite soon.

True again.

The halo around a bright celestial object is caused by the refraction of the light passing through the ice crystals that make up high cirrus clouds. Cirrus clouds are often the first to form ahead of a front.

Weather lore can give us reasonable clues to forecast the weather in our immediate area, but the predictions are short-term, not long. Sorry, Punxsutawney Phil, but there is no scientific explanation for your famous six-week weather prediction made on Groundhog Day each year.