Strong winds could weigh down the 16 large character balloons.
There's organized chaos on West 77th Street. A small army known as the Macy's inflation team is in position. Flatbed trucks brought in sandbags.
"What's the coolest part so far?" asked CBS2's Vanessa Murdock.
"Watching them blow up," said 11-year-old Ava Hearn. "Yeah, it's cool."
"It's getting earlier and earlier every year, because it gets so busy," said Upper West Sider Sarah Greig. "It's just magical to see them go all the way from the ground into the air."
"I like seeing the balloons blow up," said 5-year-old Farrell.
"I like the turkey one," said 4-year-old Ellie.
"It already feels like the holiday already. Christmas is coming. It's around the corner," said spectator Luis Raygada. He came for the first time with his 7-year-old son to get a behind-the-scenes look.
For those who live on the street, every year they have a front row seat to seeing the Macy's Thanksgiving Day Parade come to life.
"It's exciting. It's really cool. All the balloons and all of the people. It's special, I think," said Upper West Sider Jennifer Butchem.
This year, high winds may impact if the balloons make their debut at all. The NYPD plans to make the call tomorrow morning. The department will use weather instruments placed along the route and work closely with parade officials.
"These sergeants are well trained to read the anemometers to identify the height of where we can allow the balloons to go up. The balloons can actually go up to 55 feet in height, but if it comes to a situation where there is a public safety we will bring them down to ten feet," said NYPD Chief of Patrol Rodney Harrison.
WATCH: NYPD Officials Discuss Preparations For The Parade
The balloons cannot fly when sustained winds exceed 23 miles per hour with gusts over 34 miles per hour.
The only time they were grounded for bad weather was back in 1971. Safety is paramount, especially after past incidents left spectators injured.
WATCH: Macy's Creative Director Explains What To Expect From This Year's Parade
In 1997, four people were hurt when the Cat in the Hat balloon whipped around, snapping a light pole. One woman spent a month in a coma.
In 2005, an M&M balloon also snagged a pole, and the pieces fell on two sisters from Albany.
"That gives the pilot an opportunity to see – depending on what the wind pattern would be – where they need to place their handlers or have them raise up or pull down," John Piper, vice president of production for Macy's Parade Studio, told CBS2.
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