Harry Potter: Professor Trelawney's Predictions Were Actually Right...?

In the Harry Potter films, and even more so in the books, seer Sybil Trelawney made several seemingly ridiculous predictions and two real prophecies, of which she blacked out while making, but at a closer look, Trelawney was right almost all the time.

Despite being known as a fraud, Professor Trelawney is actually [almost] always right, even if the Seer cannot usually (or always) translate what she Sees properly. Here are some of her predictions starting with the 3rd book, Prisoner of Azkaban, where Trelawney's character is first introduced:

PRISONER OF AZKABAN

“The Grim!” Trelawney sees a big black dog around Harry and in his tea leaf dregs in divination, which Trelawney perceives as the dark omen known as "The Grim." The Grim takes form as a large black dog and is a sign of the subject's (Harry, in this case) untimely death. However, she isn't necessarily making this up; what Trelawney is seeing is not the Grim but actually Sirius Black, an animagus who can transform into a large black dog and who is trailing Harry at this time.

Neville's Gran

“'You, boy,' she said suddenly to Neville, who almost toppled off his pouffe, 'is your grandmother well?' 'I think so,' said Neville tremulously. 'I wouldn’t be so sure if I were you, dear,' said Professor Trelawney." Neville’s grandmother is never revealed to be ill, but what Trelawney was likely seeing was in relation to Lupin's boggart lesson, which occurs shortly after this prediction. When the boggart in Defense Against the Dark Arts class sees Neville, it transforms into his worst fear, Snape, before Neville defeats it by transforming it in turn into something "Riddikulus"--Snape in Neville’s grandmother’s clothes.

"Beware a Red-Haired Man!"

“'By the way, my dear,'” she shot suddenly at Parvati Patil, 'beware a red-haired man.'” Parvati glares at red-haired Ron, but Ron doesn't think he is to whom the red man refers. However, the next year, Parvati’s identical twin Padma goes to the Yule Ball with Ron, who shows her a truly awful time.

“And Around Easter, One of Our Number Will Leave Us Forever.”

While the class and Trelawney assume this means one student will die around Easter, this likely refers to Hermione, who, right before Easter Break, walks out mid-class, and never returns to that classroom for the remainder of the series.

“Thank You, My Dear. Incidentally, that thing you are dreading – it will happen on Friday the sixteenth of October.” Lavender later thinks this prediction refers her rabbit Binky dying, as she receives the news on the 16th of October. But, and this is a stretch, it may refer to what all the students feared—Sirius Black. On October 31st, he breaks in to Gryffindor Tower... Could Trelawney have mixed up these events that would both affect Lavender? It's possible, at best.

“If you must know, Minerva, I have seen that poor Professor Lupin will not be with us for very long. He seems aware, himself, that his time is short.” Well, you know. Lupin, like all Defense teachers, leaves Hogwarts by the end of the school year.

“I dare not, Headmaster! If I join the table, we shall be thirteen! Nothing could be more unlucky! Never forget that when thirteen dine together, the first to rise will be the first to die!” At the Christmas feast, Trelawney sees 12 seated at the dinner table in The Great Hall, and after she sits, making their number 13, Ron and Harry stand first at almost the same time, so one of them must be the first to die. However, Ron has Peter Pettigrew/Scabbers in his pocket. So 13 were already seated before Trelawney sat down, and the first to rise before she sat was Dumbledore when he stood up to greet her. Dumbledore dies before any other character seated at that table.

“I have decided to introduce the crystal ball a little earlier than I had planned. The fates have informed me that your examination in June will concern the Orb.” This appears silly, as she is the one who plans the exam. However, she was actually seeing something. During the final exam, she gives the second of her two real prophecies (not predictions), this time about Peter Pettigrew rejoining The Dark Lord.

Prophecies are stored in orbs.

GOBLET OF FIRE

“I was saying that Saturn was surely in a position of power in the heavens at the moment of your birth… your dark hair… your mean stature… tragic losses so young in life… I think I am right in saying, my dear, that you were born in midwinter?” What Trelawney is seeing here isn’t Harry, but the part of him that is the horcrux—Voldemort. Tom Riddle is dark haired, had a tragic young life, and was born December 31st.

“Death, my dears. Yes, it comes ever closer.” Aaaand then Cedric dies.

ORDER OF THE PHOENIX

“I — but — but — wait! I… I think I do see something… something that concerns you… Why, I sense something… something dark… some grave peril… I am afraid… I am afraid that you are in grave danger!” She says this a lot, but this is to Umbridge, who is later carried off and nearly killed by a herd of centaurs, saved only when Dumbledore convinces them to free her.

HALF-BLOOD PRINCE

“'Two of spades: conflict,' she murmured, as she passed the place where Harry crouched, hidden. 'Seven of spades: an ill omen. Ten of spades: violence. Knave of spades: a dark young man, possibly troubled, one who dislikes the questioner. . . . lightning-struck tower. . . . calamity and disaster.'” The two of spades refers to Draco, who is deeply troubled in his orders from Voldemort to kill Dumbledore. Later, a battle breaks out at Hogwarts where a Death Eater is killed and Bill Weasley is bitten by the werewolf Fenrir Greyback. During this battle, Dumbledore arrives on top of The Astronomy Tower with Harry, the latter under his invisibility cloak, where Dumbledore meets and questions Draco... for quite a while, I might add.

When Dumbledore is killed minutes later, it is in the chapter named “The Lightning Struck Tower”--the name of the final Tarot card Trelawney pulled.