WEEKEND SNOWSTORM STRIKES THE NORTHEAST CORRIDOR
CLASSIFIED AS A CATEGORY 3 "MAJOR" STORM

The weekend snowstorm that struck the eastern seaboard and brought airlines and roadways to a standstill in some of the nation’s biggest cities was classified as “Major” or a Category 3 storm on the new Northeast Snowfall Impact Scale, or NESIS, scale, according to NOAA’s National Climatic Data Center in Asheville, N.C.

This is a preliminary classification based on the snowfall observations available at this time. NESIS, which NOAA made operational this winter, ranked this Northeast storm as having the 20th biggest impact out of a sample of 32 storms that have occurred between 1956 and 2006.

NESIS ranks the severity of an East Coast snowstorm based on snowfall amount and the population of the affected areas. NESIS allows scientists to quickly assess a snowstorm’s potential impact, compare it with a storm of the past and assign it one of five categories: Notable, Significant, Major, Crippling or Extreme.

Near-blizzard conditions prevailed in the Northeast over the weekend, with winds gusting more than 50 mph along the coastal areas. The strong winds produced snow drifts more than four feet high and made snow measurements difficult. Review and quality control of the reported snowfall amounts are required before these reports are officially accepted as new snowfall records, NCDC officials said.

According to preliminary reports, new single-storm and 24-hour snowfall records were established in some locations. In New York City’s Central Park, where record-keeping began in 1869, 26.9 inches of snow fell between 4 p.m. Saturday and 4 p.m. Sunday, breaking the previous storm total record of 26.4 inches set during a December 26-27, 1947 storm. In Hartford, Conn., a total of 21.9 inches broke the old storm total record of 21 inches set in 1983. These high amounts tend to occur in isolated locations or within narrow bands, and were surrounded by reports of 10 to 20 inches.

More than six inches of snow fell across a large region from the Appalachians of North Carolina to the most heavily populated areas of the Northeast. Reports of more than 12 inches were widespread across the region, and the highest snowfall amounts fell from New York City to Connecticut. Other snow storms of the recent past, such as the 1993 Storm of the Century (NESIS Category 5) and the January Blizzard of 1996 covered areas throughout the eastern U.S., while also bringing heavy snowfall to interior regions. However, the development and movement of this storm off the Atlantic coast produced the highest storm totals along the coastal corridor, while missing areas from western Pennsylvania to northern New England.

NESIS was jointly developed by Paul J. Kocin, a winter storm expert at The Weather Channel and Dr. Louis W. Uccellini, director of NOAA’s National Centers for Environmental Prediction in Camp Springs, Md. Thomas R. Karl, director of NOAA’s National Climatic Data Center in Asheville, N.C., led the effort to compute NESIS starting with this season’s snowstorms.

NOAA, the National Oceanic and Atmospheric Administration, an agency of the U.S. Commerce Department, is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of our nation’s coastal and marine resources. Through the emerging Global Earth Observation System of Systems (GEOSS), NOAA is working with its federal partners and 60 countries to develop a global monitoring network that is as integrated as the planet it observes.

On the Web:

NOAA: http://www.noaa.gov

NOAA’s National Centers for Environmental Prediction: http://www.ncep.noaa.gov

National Climatic Data Center: http://www.ncdc.noaa.gov