The whopper of a storm didn't rank high in history

20:58, Feb 12 2013
Winter Storm Nemo
A pedestrian and car make their way through heavy snow in Somerville, Massachusetts during Winter Storm Nemo.
Winter Storm Nemo
A woman walks her dog down a street in the Beacon Hill area of Boston, Massachusetts as heavy snow falls.
Winter Storm Nemo
Steve Young shovels snow from his sidewalk in Boston, Massachusetts, during Winter Storm Nemo.
Winter Storm Nemo
The skyline of lower Manhattan, New York, after Winter Storm Nemo passed.
Winter Storm Nemo
A child makes the best of the snow, sliding down a hill on a toboggan in Jersey City, New Jersey.
Winter Storm Nemo
Snow partially covers cars in a street in Jersey City, New Jersey.

The snowstorm that walloped the US northeast with about 91 centimetres in some places didn't add up to being that bad, federal statistics say.

Two National Oceanic and Atmospheric Administration storm-rating measurements initially ranked Friday's snowstorm as 16th in US northeast history by one scale and 25th by another.

The two storm measurement systems are similar in scale to the ones that measure hurricanes and tornadoes. They rank the weekend storm as a 3 and "major" on a 1 to 5 scale. It didn't rate a "crippling" 4 or "extreme" 5.

"I was a bit surprised; I thought it would have been a 4 or a 5," said National Climatic Data Center meteorologist Mike Squires. "The footprint of really heavy snow over populated areas was relatively small compared to other storms we have looked at."

Meteorologists look at the really big snow — measuring more than 76cm — and only 309 square kilometres populated by 49,000 people got that much. To be crippling or extreme, those numbers have to be much higher, Squires said. Only eight weather stations out of 1,365 had 76cm  of snow, he said.

The snowstorm measuring systems take into account the size of the snowstorm, the amount of snow and how many people were in its path. But they do not take into account high winds — some in this storm reached hurricane force — or drifting snow.

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On the older and more nationally oriented Northeast Snow Impact Scale, which looks at snow in the entire history of a storm, the weekend storm's total score was 4.35, ranking it 25th. That's far behind the No. 1 1993 Storm of the Century and the more famous 1978 blizzard that ranked 13th.

In the newer and more area-specific Regional Snowfall Index, this recent storm came in behind the No. 1 storm in 1969 and ranked a more respectable 16th with a 9.04 total score.

Some other statistics show more severe weather: Worcester, in Massachusettes, had eight hours of blizzard conditions, with seven other cities having official blizzard conditions for three or more hours.

On Saturday in Boston, 37.6cm of snow fell in one day, breaking the record from 1994. Portland, Maine, got a record 81cm of snow, smashing the old record by nearly 12.7cm. Snow records were also set in Bridgeport and Hartford in Connecticut. There is a still-to-be-resolved question about the quality of snowfall data in Portland, and most of the nearby stations aren't over 76cm, Squires said. 

AP