I don't remember if Harry is a Morning person or not, I feel like he is pretty grumpy
Well, I ended up writing about Harry's sleep habits in general since it was interesting to me, so you're getting a little more than you bargained for here.
Harry is often mentioned waking up early. He is probably used to it from the Dursleys and whenever he's excited or anxious even more so:
Harry woke at five oâclock the next morning and was too excited and nervous to go back to sleep. He got up and pulled on his jeans because he didnât want to walk into the station in his wizardâs robes â heâd change on the train.Â
Harry woke early on Saturday morning and lay for a while thinking about the coming Quidditch match. He was nervous, mainly at the thought of what Wood would say if Gryffindor lost, but also at the idea of facing a team mounted on the fastest racing brooms gold could buy.Â
Harry woke early next morning, wrapped in a sleeping bag on the drawing room floor. A chink of sky was visible between the heavy curtains: It was the cool, clear blue of watered ink, somewhere between night and dawn, and everything was quiet except for Ron and Hermioneâs slow, deep breathing. Harry glanced over at the dark shapes they made on the floor beside him.
When he's nervous or anxious he also struggles to fall asleep to begin with, and doesn't sleep a lot at all:
Harry went to bed with his head buzzing with the same question. Neville was snoring loudly, but Harry couldnât sleep. He tried to empty his mind â he needed to sleep, he had to, he had his first Quidditch match in a few hours â but the expression on Snapeâs face when Harry had seen his leg wasnât easy to forget.
A hundred and fifty points lost. That put Gryffindor in last place. In one night, theyâd ruined any chance Gryffindor had had for the House Cup. Harry felt as though the bottom had dropped out of his stomach. How could they ever make up for this? Harry didnât sleep all night.
âHarry, you â you look terrible.â
Harry hadnât gotten to sleep until daybreak.Â
He thought of the letter he had written to Sirius before leaving Privet Drive. Would Sirius have gotten it yet? When would he reply? Harry lay looking up at the canvas, but no flying fantasies came to him now to ease him to sleep, and it was a long time after Charlieâs snores filled the tent that Harry finally dozed off.
Feeling disappointed, Harry threw the book back into his trunk, turned off the lamp, and rolled over, thinking of werewolves and Snape, Stan Shunpike and the Half-Blood Prince, and finally falling into an uneasy sleep full of creeping shadows and the cries of bitten children. ...
Harry did not sleep well that night. He lay awake for what felt like hours, wondering how Malfoy was using the Room of Requirement and what he, Harry, would see when he went in there the following day
And he seems to get up and get ready immediately when he gets up, he doesn't dwindle in bed and struggles to wake up:
Harry woke on the last day of the holidays, thinking that he would at least meet Ron and Hermione tomorrow, on the Hogwarts Express. He got up, dressed, went for a last look at the Firebolt, and was just wondering where heâd have lunch, when someone yelled his name and he turned.
Even when he is startled awake by something happening:
Harry woke as suddenly as though heâd been hit in the face. Disoriented in the total darkness, he fumbled with his hangings â he could hear movements around him, and Seamus Finniganâs voice from the other side of the room: âWhatâs going on?â
Early next morning, Harry woke with a plan fully formed in his mind, as though his sleeping brain had been working on it all night. He got up, dressed in the pale dawn light, left the dormitory without waking Ron, and went back down to the deserted common room.
And he doesn't really sleep in late (unless he didn't sleep at all the night before, which happens a few times). At least not that I could find. The only time he seems to be sleepy and wants to stay in bed lazily I could find is when he is given a dreamless sleep potion:
Harry took the goblet and drank a few mouthfuls. He felt himself becoming drowsy at once. Everything around him became hazy; the lamps around the hospital wing seemed to be winking at him in a friendly way through the screen around his bed; his body felt as though it was sinking deeper into the warmth of the feather matress. Before he could finish the potion, before he could say another word, his exhaustion had carried him off to sleep.
Harry woke up, so warm, so very sleepy, that he didnât open his eyes, wanting to drop off again. The room was still dimly lit; he was sure it was still nighttime and had a feeling that he couldnât have been asleep very long.
It also seems that once he's awake (even if very early) Harry struggles falling back asleep:
Harry fumbled for his alarm clock and looked at it. It was half past four. Cursing Peeves, he rolled over and tried to get back to sleep, but it was very difficult, now that he was awake, to ignore the sounds of the thunder rumbling overhead, the pounding of the wind against the castle walls, and the distant creaking of the trees in the Forbidden Forest. In a few hours he would be out on the Quidditch field, battling through that gale. Finally, he gave up any thought of more sleep, got up, dressed, picked up his Nimbus Two Thousand, and walked quietly out of the dormitory.
And all of this makes sense. Trauma and PTSD can affect sleep very negatively. Since OotP, Harry has many uneasy, nightmare-filled nights:
Harry had a troubled nightâs sleep.Â
In the meantime, he had nothing to look forward to but another restless, disturbed night, because even when he escaped nightmares about Cedric he had unsettling dreams about long dark corridors, all finishing in dead ends and locked doors, which he supposed had something to do with the trapped feeling he had when he was awake.Â
After two nights of little sleep, Harryâs senses seemed more alert than usual.
Actually, the nightmares and restless nights are there prior to OotP too, this kid is so traumatized:
Harry wished he could forget what heâd seen in the mirror as easily, but he couldnât. He started having nightmares. Over and over again he dreamed about his parents disappearing in a flash of green light, while a high voice cackled with laughter.
As I mentioned, Harry doesn't sleep well when he's anxious, stressed, or excited, and for this kid, it's basically always. So, I think Harry tends to wake up on the earlier side of things and is capable of functioning decently (if angrier) on little to no sleep.
Since I was looking for info on Harry's sleep, apparently, depending on the position he falls asleep in, he snores, loudly:
Harry Potter was snoring loudly. He had been sitting in a chair beside his bedroom window for the best part of four hours, staring out at the darkening street, and had finally fallen asleep with one side of his face pressed against the cold windowpane, his glasses askew and his mouth wide open.
(As a general note, Ron and Neville snore too)