Photo via NewscomJoan Jett will perform in the Macy’s Thanksgiving Day Parade Thursday on NBC.

So what if Christmas decorations popped up on store shelves before Halloween? The season officially begins Thursday morning with the parade.

Yes, this is one of the few things in life so famous that it can be referred to that generally. Specifically, it is the Macy’s Thanksgiving Day Parade.

For those keeping track, this is the 87th parade (it began in 1924 but was suspended 1942-44 during World War II). For three hours on NBC Thursday morning, it’s a fair bet most people are watching “Today” regulars Al Roker, Matt Lauer and Savannah Guthrie chat about the lineup that includes the cast of “Duck Dynasty,” Cirque du Soleil and Florida Georgia Line.

Jimmy Fallon and the Roots jam with the cast of “Sesame Street.” The Rockettes will high-kick in front of the landmark 34th Street store, and casts from Broadway’s “Motown: The Musical,” “Matilda” and “The Sound of Music Live!” are scheduled to perform.

To mark the 75th anniversary of “The Wizard of Oz,” a 47-foot-high hot-air balloon emblazoned with the film’s characters debuts. Look closely in the balloon’s basket — a young woman is trying to get back to Kansas.

Some 50 million are expected to watch at home, while an anticipated 3.5 million will line the parade route.

“That’s what everybody does that day,” says Kellie Pickler, who will perform her new single, “Little Bit Gypsy.”

“Every kid that watches the parade thinks that it would be fun to be there and see the parade in person,” Pickler says. “Sometimes the best seats are the ones at home on your couch. I am sure it will be crowded like it is at New Year’s. I was there to help with Dick Clark’s New Year’s, and New Year’s Eve is insane.”

Pickler is preparing to be in her first parade, as is Joan Jett, who’s performing from her new album, “Unvarnished.”

Jett, who lives in New York, was supposed to be on a float from South Dakota because that state’s secretary of state, a major Blackhearts fan, invited her. But her committed stance against eating meat infuriated South Dakota ranchers, so she was being moved to another float, which was not yet known at this writing.

Though the parade usually features country, pop and Broadway, Jett was pleased to bring a punkier sound to the party.

“When we play around the country, in all sorts of places, I am always pretty astounded by the variety of audience we attract playing our kind of rock and roll,” Jett says. “All ages, all stripes of political persuasion. Music transcends a lot of those barriers, which is what I think music is supposed to do. It is supposed to bring them together rather than pull them apart.”

That’s precisely what this parade does. While so many parades that wend through Manhattan celebrate specific cultures, the Thanksgiving parade embraces all. Plus, it just makes people happy. Witness John Piper, vice president of Macy’s Parade Studio.

“How could you not be excited?” he asks.

Interviews with Piper over the years reveal a man genuinely thrilled by the mechanics of balloons and floats and making it all magical. Balloons are inflated the day before, and that process has become such an attraction, the work is spread throughout the day and evening so it’s not too crowded near the American Museum of Natural History, where deflated balloons are trucked in from the parade’s New Jersey studio.

And a bit of parade humor: What’s the difference between inflating and blowing up a balloon? “About one second,” Piper says.

Among the new attractions this year is a giant spinning dreidel. The eight-night festival of Hanukkah begins Wednesday.

There’s also a new Snoopy balloon. He’s flying with his buddy Woodstock. And there’s a new SpongeBob SquarePants balloon, topped with an enormous red Santa hat that has a 6-foot-wide bell.

Toothless from “How to Train Your Dragon” joins the parade and is a rather majestic 72 feet long. His wings are folded in, otherwise they would spread over Central Park, Piper says.

“He will be peeking in quite a few windows,” Piper says. “For those who have not seen ‘How to Train Your Dragon,’ we may have a few people surprised. He is a night fury dragon. He is a wonderful, very, very dark bluish-black color with scales and fluorescent green eyes.”

As always, the parade’s numbers are impressive. This year features 15 giant character balloons; 37 smaller, but still large, novelty balloons; 30 floats; 1,600 cheerleaders and dancers; 900 clowns; and 11 marching bands.

“There is never a year when there doesn’t come a time and I am in the golf cart, and I may be on my way to check on a float, and (handlers of) one of the balloons does their cheer, or someone on a float waves to the crowd, or Texas or Ohio or Michigan or Wyoming breaks into a fight song, and everybody on the parade route turns into a kid,” Piper says. “And they just exude so much happiness, and it just flows, and if you are there, you are just caught up in it that moment. That is what it is all about.”