As the ball drops in Times Square, so might snow across New York City.

Light snowfall is expected Wednesday night throughout the region, starting as early as 9 p.m., according to the National Weather Service. Most of it will happen between midnight and 5 a.m. Thursday, leaving up to a half-inch of snow, NWS meteorologist James Tomasini said.

“Because temperatures are really not warming up too much today, and then they're going to drop below freezing right after sunset, it's likely surfaces will actually be cold enough for it to stick, especially to any grassy surfaces,” he said.

This would be the first time the city has gotten snow late on New Year’s Eve since 2009, Tomasini added. He advised New Yorkers going out to celebrate the holiday to beware of slick spots on roads and sidewalks, particularly untreated areas.

Temperatures on Wednesday will hover in the low 30s during the day, then drop to the mid-to-low 20s in the evening, with wind chills making it feel as low as the upper teens, according to NWS. That’s around 10 degrees lower than normal for this time of year, Tomasini said, and temperatures are predicted to stay around that level for the next several days.

The snowfall and frosty temperatures are a result of a low-pressure system moving north of the city and a cold front moving through the area, he said.

New York City’s Emergency Management agency said a code blue for increased street outreach to homeless residents will take effect Wednesday until Thursday, so outreach workers will aim to connect them to shelter.

“If you are heading out, wear warm layers, a hat, gloves, and insulated footwear with good traction,” the agency tweeted. “Pack extra layers and keep your phone charged. Do not drink and drive. Plan a safe ride home, use mass transit.”

New Yorkers wanting to stay posted on weather and New Year’s Eve information from the city can sign up for official updates from the Notify NYC system by texting NEWYEARSEVE to 692692, or NOCHEVIEJA for Spanish.