Birds flying low
Birds flying low often signal that rain is near: as humid air moves in, the insects that swallows hunt drift lower, and the birds follow them down. Observers from England to Madagascar noticed the same thing.
What it may mean
Swallows skimming a few inches above a field or a pond often signal rain on the way, and people noticed it in many places. Willsford's Nature's Secrets, as Brand quotes it, said swallows flying low and touching the water with their wings presage rain; in Germany, a 1903 encyclopedia says, low swallows foretold a storm, and in Madagascar, rain. The birds are not forecasting anything. As humid, unsettled air moves in, the small insects they hunt drift lower, and the birds come down to where dinner went. They do not hold out at their usual height out of pride. People find that move harder. When the work, the friends or the energy that feed them shift to a lower, less impressive level, many keep circling where things used to be. The swallow over the wet grass has already followed the food.
Depending on how you saw it
Gnats hanging low over the path
In Persia, a 1903 encyclopedia says, gnats flying low were a sign that rain was coming, and the birds that eat them follow close behind. Small things move first. What tells you to change your plans for the day before the forecast does?
Sparrows close to the ground
In Bohemia, sparrows flying close to the ground counted as a rain sign, along with worms coming up and lizards hiding. Working near the ground for a while is no defeat for a bird. Where are you working closer to the ground than usual, and is that so bad?
Then the birds disappear
Just before a storm breaks, the low-flying birds often vanish into hedges, barns and eaves, and the air goes still. They know when feeding time is over. Where do you take cover when you feel the pressure building?
Why it happens in nature
Before rain, humid, unsettled air and weaker updrafts keep many small flying insects closer to the ground, so swallows, swifts and martins that catch insects in flight hunt low over fields and water. On fine, sunny days, rising warm air carries the same insects higher, and the birds feed high overhead.
What folk beliefs say
England
Brand quotes Willsford's Nature's Secrets: swallows flying low, and touching the water often with their wings, presage rain.
Source: John Brand; Henry Ellis (ed.), Observations on the Popular Antiquities of Great Britain, vol. 3 (1849), vol. 3, p. 194. View the page
Germany
When swallows fly low above the ground, a 1903 collection says, it is a German sign of a storm.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 706. View the page
Madagascar
In Madagascar, when the swallow flies low, it will rain.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 707. View the page
Persia (Iran)
In Persia, when gnats fly low, rain is coming.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 637. View the page
Bohemia
In Bohemia, sparrows flying close to the ground were among the signs of rain.
Source: Cora Linn Daniels; C. M. Stevans (eds.), Encyclopaedia of Superstitions, Folklore, and the Occult Sciences of the World, vol. 2 (1903), vol. 2, p. 972. View the page
To reflect on
Where has the thing that feeds you moved lately, and have you followed it there?