Last winter’s East Coast blizzard has set another record, in New York City, while a record in Newark, New Jersey, was deleted, the National Oceanic and Atmospheric Administration said Thursday in a report prompted by questions about the accuracy of snowfall measurements.
The review also found that widely reported suspicions about a 17.8-inch measurement at Reagan National Airport near Washington were unfounded. Although substantially lower than readings within the District of Columbia, the number was close to totals from nearby sites in northern Virginia, the agency said.
The blizzard Jan. 22-23 dropped more than 40 inches of snow in some areas and broke many records. It also underscored a known problem of some weather observers failing to follow standards established by the National Weather Service, the report says. So NOAA, which includes the weather service, established a “snow measurement team” that reviewed data from eight locations from Washington to New York.
The agency said the 26.8-inch total reported by the National Weather Service for New York’s Central Park will be changed to an all-time record 27.5 inches. The error stemmed from miscommunication between the Central Park Conservancy, which correctly measured the snowfall, and the weather service’s New York forecast office, the report says.
“Snow measurements are extremely difficult to take because precipitation is inherently variable, a problem compounded by strong winds and compaction during a long duration event,” National Weather Service Director Louis Uccellini, said in a statement. “Still, it’s important that we scrutinize questionable measurements and reject those that scientists deem invalid to ensure the public’s continued confidence in the U.S. climate record.”
The report upholds the long-approved practice of measuring snowfall with 2-foot-square white boards, checked every six hours. But it recommends adding flags to the boards so they can be found even when buried in snow, as happened at Reagan National.
Checking the boards too frequently can inflate the measurement. The report says that’s what happened at Newark Liberty International Airport, where contract weather observers took hourly measurements and reported an all-time record of 28.1 inches. The review team found that weather observers there may have been measuring snowfall improperly since 1996.
“A separate team will investigate the best course of action to determine the accurate snowfall total and, as appropriate, amounts may be changed,” the report says. Meanwhile, the Newark observers have been re-trained on the proper procedures, the agency said.