As of Tuesday, North America is covered by the third-highest amount of snow this late in the season since records began in 1966, according to NOAA’s U.S. National Ice Center. Only 1969 and 1978 had more snow cover at this point in the year, according to Sean Helfrich of NOAA’s National Ice Center. This data includes both the U.S. and Canada, reported New Jersey state climatologist and Rutgers University geography professor David Robinson. “Given that the vast majority of Canada is snow-covered at this time of the year (except in a very mild early March), the signal is virtually entirely a function of snow extent variations in the lower 48,” he said in an e-mail.