Não tenho certeza se poderia haver uma resposta definitiva para essa pergunta.
The ways of the centaur are shrouded in mystery. They are generally speaking as mistrustful of wizards as they are of Muggles and indeed seem to make little differentiation between us. They live in herds ranging in size from ten to fifty members. They are reputed to be well-versed in magical healing, divination, archery, and astronomy.
Fantastic Beasts and Where to Find Them - page 6 - Scholastic - An A-Z of Fantastic Beasts
Reputação significa que é suposto ser , por isso é possível que haja nenhuma previsão específica para apontar no cânon que é por um centauro. Se eu encontrar algo, vou editá-lo.
ETA: não consigo encontrar nada que seja um bom exemplo. Em Pedra Filosofal , diz:
‘Good luck, Harry Potter,’ said Firenze. ‘The planets have been read wrongly before now, even by centaurs. I hope this is one of those times.’
Philosopher's Stone - page 189 - Bloomsbury - chapter 15, The Forbidden Forest
Firenze não diz o que está vendo nos planetas, então não sabemos o que estamos procurando como previsão. Parece óbvio que isso tem a ver com Harry e Voldemort, com Harry não favorecido ao triunfo. Então, em Ordem da Fênix , Firenze observa o seguinte:
‘In the past decade, the indications have been that wizardkind is living through nothing more than a brief calm between two wars. Mars, bringer of battle, shines brightly above us, suggesting that the fight must soon break out again. How soon, centaurs may attempt to divine by the burning of certain herbs and leaves, by the observation of fume and flame ...’
Order of the Phoenix - page 532 - Bloomsbury - chapter 27, The Centaur and the Sneak
Eu não acho que isso seja uma previsão por si só; na época da Ordem da Fênix , que outra guerra de feiticeiros era iminente era completamente óbvia. Se Firenze tivesse dito isso em Filosofal Stone , eu poderia olhar de outra maneira. Finalmente, em Ordem da Fênix , Firenze observa, basicamente, que a adivinhação deve ser tomada com um grão de sal.
Firenze told them to look for certain shapes and symbols in the pungent fumes, but he seemed perfectly unconcerned that not one of them could see any of the signs he described, telling them that humans were hardly ever good at this, that it took centaurs years and years to become competent, and finished by telling them that it was foolish to put too much faith in such things, anyway, because even centaurs sometimes read them wrongly. He was nothing like any human teacher Harry had ever had. His priority did not seem to be to teach them what he knew, but rather to impress upon them that nothing, not even centaurs’ knowledge, was foolproof.
Order of the Phoenix - page 532 - Bloomsbury - chapter 27, The Centaur and the Sneak
Acho que a coisa mais próxima de uma previsão é que nada é infalível.