The science of weather forecasting is sharpening in accuracy at a steady pace, with a five-day forecast now as accurate as a two-day forecast was 20 years ago.
Despite this scientific progress, you’ll still hear the fond recital of weather folklore to predict tomorrow’s weather.
‘Red sky at night, shepherds’ delight. Red sky in the morning, shepherds’ warning’: This is probably the most popular of weather folklore, the substitution of ‘sailor’ for ‘shepherd’ is actually an American take on the same notion; a red sky during the evening heralds good weather for tomorrow, whilst a red sky in the morning heralds bad weather in the coming day.
‘Red sky’ merely refers to cloud that is lit-up red by the rising or setting sun. It is often high cloud that gives the most stunning displays, as it remains illuminated long after the sun has set below the horizon. High cloud often precedes, and follows, large bands of cloud and rain known as fronts.
Frontal rain clouds often gather in the west then move eastwards across the country. If you can see the setting sun in the west, the chances are there are no frontal clouds there to obscure it.
If this setting sun is illuminating high cloud above us, this cloud may well be associated with a band of rain clearing to the east. So, a red sky at night gives an indication of a nice day tomorrow and much delight for British shepherds.
Alternatively, if the rising sun in the eastern sky is lighting up overhead cloud, this may well be associated with fronts gathering in the west, bringing rain later and ruining the shepherds’ day.
So there is scientific support for this folklore, though it doesn’t always work.
We also consult the animal kingdom for alternative weather predictions. Seagulls sitting in fields away from the sea, or cows facing the same way with their backs to the wind, is a prediction of bad weather, apparently. In reality, they’re probably confirming that the weather is already bad as, much like humans, cows aren’t fans of wind and rain-blasted faces and seagulls prefer not to weather-out storms in the air or on the open water.
Some people believe their pets can predict the onset of thunderstorms with changes in their behaviour. As someone who often suffers mild headaches in the hours before a thunderstorm, I can believe there may be something in this.
It may be due to increased static build-up or an increase in humidity, or it may simply be that my over-excitement when storms are due is unhealthy for me.
Whether you believe in weather folk-lore or not, we’re looking at a change in the weather over the next few days. After what has been a very showery week, it looks like tomorrow, Friday and Saturday should be mostly dry with sunny spells. The cloud may thicken to give the odd isolated shower and it will certainly be colder than recently with daytime highs of only 11 or 12 degrees.
Aylesbury Vale gardeners should be aware that night-time temperatures will fall low enough for grass frost.