7+ inches of snow: Why did the storm hit so hard?

Gene Myers | NorthJersey

Show Caption Hide Caption North Jersey snow on Rt 46 in Totowa North Jersey snow on Rt 46 in Totowa

NORTH JERSEY — It was a heavy storm that hit harder than expected — a storm that puzzled experts as North Jersey dug out on Friday.

"It will go down in the annals as one of the more notable November snowstorms," said state climatologist David Robinson of Rutgers University.

On Thursday afternoon, the National Weather Service changed its Winter Weather Advisory to a Winter Storm Warning for parts of Bergen and Passaic counties as it realized North Jersey was about to get dumped on.

Weather models had predicted just 2 inches of snow and a tenth of an inch of freezing rain as recently as Wednesday night, according to Joe Pollina, a meteorologist with the National Weather Service.

But by 12:30 p.m. Thursday afternoon Pollina said the picture had changed and forecasts called for 4 to 8 inches of snow.

“We had some heavy precipitation move in yesterday afternoon and into the overnight hours as a low-pressure system approached from the southwest,” Pollina said Friday. “The precip was a little heavier than forecasted at the time. That was a factor.”

Other factors meteorologists take into account include wind strength, ground temperature and air temperature.

“It looked like there was going to be more precipitation at the onset of the storm while the cold air was still in place,” said Pollina.

That pushed accumulations closer to the top of the projected range, Pollina said. Hawthorne ended up getting 7 inches of snow. Westwood saw 7.8 inches and Franklin Lakes got a total of 7.2 inches.

Robinson said his numbers are still preliminary, but Tenafly got 6.6 inches. Seven inches of snow landed in Palisades Park and some places, like Randolph in Morris County saw as much as 10 inches, Robinson said.

“The amount of snow that fell this early in the season was definitely atypical,” said Pollina.

To put it more bluntly, Robinson said, "to get a plowable snow this time of year, all of the stars have to align."

A look ahead: First snow storm is over, but what will the rest of the winter be like in New Jersey?

Column: New Jersey commuters wanted snow plows, Phil Murphy gave them excuses

Snowstorm NJ 2018: Here's how Thursday's commute turned into complete chaos

A heavy burst of precipitation that came quickly and fiercely was key.

"The snow came with such an intensity that it was self-perpetuating. It kept the air cold all throughout the atmosphere down to the surface," Robinson said.

Pollina said the storm will be studied in the days to come.

“Maybe it was a little too late but we did catch on to what we were seeing,” Pollina said.

Other notable storms include one that followed Superstorm Sandy in 2012 and a storm that "gave us a white Thanksgiving in 1989," Robinson said.

Robinson added that having three fall snowstorms in the last decade is an unusual occurrence, but it doesn't indicate a trend.

The story continues below the gallery.

The National Weather Service likes to “give a heads up to the public 24 to 36 hours beforehand with a winter storm warning" whenever there is more than 6 inches of snow predicted.

Thursday's predictions gave “a little less than 24 hours notice” because most models showed higher temperatures and lower precipitation, according to Pollina.

“It wasn’t until Thursday night model runs that they were hinting at how much snow we could see,” Pollina said.

Wind gusts in the area were between 30 and 40 mph with the strongest winds peaking at 41 mph at 10:46 p.m. Thursday night. Winds as strong as 61 mph were recorded along the coast.

Meteorologist Melissa Dispigna, also with the National Weather Service, said that outside of power outages in Hudson County, she hasn’t received many damage reports from New Jersey. However, as many as 1,500 trees were downed in New York City.

"It was a heavy, wet snow and the trees down are partly due to the wind we had and also the leaves are still on the trees, so that adds to the weight," she said.

Email: myers@northjersey.com