Long Islanders started their morning commute Thursday expecting perhaps a dusting of snow during the day. Their evening commute, however, had them brushing up to 6 inches of snow off their cars, driving at a crawl along roads choked with snow and traffic, and pulling into driveways that needed shoveling.
On Friday, many of these folks — along with New York City Mayor Bill de Blasio — were a touch upset, and felt that weather forecasters had some explaining to do.
The mayor blamed Thursday night's lengthy and chaotic commutes on the National Weather Service's initial forecast, which he said had called for just a few inches of snow.
"I think the domino effect of that was huge," de Blasio said.
Joe Pollina, a weather service meteorologist on Long Island, acknowledged that "our storm totals were a little off" and he attributed that to the "uncertainty inherent with meteorology."
That uncertainty can be even more pronounced on Long Island because it is almost surrounded by the Atlantic Ocean, and measuring all that is happening out in the water is challenging and not always perfect, he said.
Forecasters did not see early on Thursday that the cold air would remain so long over Long Island, which kept the snow falling longer than expected, Pollina said.
Pollina offered a timeline of how the weather service's forecast evolved over the day. For the service's 3:49 a.m. report, officials did not even issue a winter weather advisory for Long Island, as they expected no more than 3 inches of snow would fall..
By 12:30 p.m., the service issued a winter weather advisory for Nassau County, believing that some western parts of the county could see up to 5 inches of snow. Meteorologists saw that as the coastal storm developed, the cold high pressure system to the north was stronger than first anticipated, he said. That cold air feeds the snowstorm.
"We had forecast that it would be precipitating all day. The big question was whether it would be snow, a wintry mix or rain," Pollina said.
The cold air stayed longer over our area, he added. Much depends on what the wind coming off the Atlantic is doing, since the ocean is the source of the warm air that would keep the precipitation falling as rain.
At 2:23 p.m., the service said it expected a heavier band of snow, and the Island could see 1 to 2 inches of snow falling every hour.
By 5:38 p.m., the weather service ratcheted up its forecast to say Islanders could see up to 2 to 3 inches of snow falling per hour for the next hour or two.
Pollina said the weather service not only looked ahead to forecast the weather, but sometimes reviewed its previous forecasts to learn lessons.
"This will be a storm we look back on," he said.
News 12 Long Island Chief Meteorologist Bill Korbel said in a statement Friday morning that "the storm developed more quickly and no one caught it until shortly after noon. . . . As good as we have gotten, things like this will occasionally happen. The perfect forecast is not possible now or for the foreseeable future.”
Craig Allen, the chief meteorologist for WCBS 880 radio, said he had a bad feeling from the start about this storm, but held off going out on a limb.
"I didn't want to pull the bread and milk cord," he said, meaning that he didn't want to create a storm panic.
Instead, he offered some hints early on in the morning that he was nervous about the storm and that he thought the evening commute was going to be a bear.
By 1 p.m., Allen told his listeners that the Island could get up to a 6-inch snowfall.
"I felt it in my stomach," he said.
With Matthew Chayes