Cat crying at night
A cat crying at night is most often two cats negotiating a boundary, or a female in heat and the males who answer her. Old Irish lore heard trouble in the sound; the cats themselves are working hard to avoid a fight.
What it may mean
The sound that makes people sit up in bed, a wail like a baby's from the dark yard, is usually two cats negotiating. Toms meeting at a boundary, or a male answering a female in heat, can yowl at each other for twenty minutes without touching. The noise is the point: each cat is trying to win without a fight, because a real fight costs both of them. Old Irish lore heard that cry as a warning of trouble, which is easy to understand at three in the morning. The cats themselves are doing something quite sensible, putting all their effort into sound so they can skip the scratches. People could do worse. A disagreement stated loudly and clearly is often the one that never has to turn into a real fight. For many cat owners, the noise is simply the price of an open window.
Depending on how you saw it
A wail that sounds like a baby
A female cat in heat calls loudly and repeatedly for several days, and in season it can come back every few weeks. The sound carries far on still nights. When something cries out again and again near you, how do you tell distress from plain noise?
Two cats facing off in the yard
Rival cats stare, puff up and trade long, rising yowls, and most standoffs end with one cat slowly walking away. The loser keeps its dignity and its fur. Where would a clear "this is my line" save you from a real fight?
Your own cat crying at the door
Cats that cry at a door at night want out, want in, or want company, and they quickly learn which call gets an answer. A routine often settles it. Which request repeated every night in your home deserves a real answer instead of a sigh?
A scream that turns out to be a fox
Red foxes scream on winter nights during their mating season, and the sound is easily taken for a cat, or even a person. Seeing the fox ends the mystery at once. What noise around you turned out to have a different source than you assumed?
Why it happens in nature
Unspayed female cats call loudly and often when in heat, and males answer and challenge one another from dusk until dawn. Yowling between rival cats is a standoff that often ends without contact. In many areas red foxes also scream on winter nights in their mating season, a sound easily mistaken for a cat.
What folk beliefs say
Ireland
Irish belief held that when cats in their quarrels kept up for days that peculiar cry which sounds like a baby in distress, disaster and death were close at hand for the one who heard them.
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. 592. View the page
England
An English book of popular questions, the Supplement to the Athenian Oracle, quoted by Brand, said that common people took the crying of cats on rooftops at night, like that of ravens, as a sign of death for the sick.
Source: John Brand; Henry Ellis (ed.), Observations on the Popular Antiquities of Great Britain, vol. 3 (1849), vol. 3, p. 188. View the page
To reflect on
Which disagreement of yours could be settled by saying it clearly, before it turns into a real fight?