Northeast blizzard sets records as experts call it a “classic” bomb cyclone

The nor’easter smacking much of the Northeast with nearly 3 feet of snow in places intensified quickly into what meteorologists said was a “bomb cyclone,” bringing thundersnow and lightning to an event that also ranked among the most intense storms on record in the region. Meteorologists described the storm as classic in its power and, at least among weather experts, as a rare convergence of conditions that favored extreme snowfall. While the storm paralyzed travel and threatened residents along the Eastern Seaboard, the weather itself also drew awe for its intensity and unusual electrified characteristics.

Meteorologists said the storm qualified as a “bomb cyclone” as it rapidly strengthened, noting that storm strength is measured by the atmospheric pressure at the storm’s center and that lower pressure signals greater intensity. Owen Shieh, warning coordination meteorologist at the National Weather Service’s Weather Prediction Center in Maryland, said the nor’easter dropped 39 millibars in 24 hours—passing the 24 millibars per day threshold used to classify “bombogenesis” or a “bomb cyclone.” Jeff Masters, co-founder of Weather Underground and now a meteorologist at Yale Climate Connections, said the setup reflected the strongest ingredients for extreme outcomes, and he compared the storm’s intensity to “a hurricane with snow.”

Shieh said Providence, Rhode Island, set an all-time snowfall record at 33.5 inches (85.1 centimeters) by about midday Monday, beating the previous record set in 1978, as the snow was still falling. The highest total reported so far, meteorologists said, was in Warwick, Rhode Island, which barely passed 3 feet at 36.2 inches (92 centimeters). The National Weather Service office in Boston also reported substantial totals elsewhere, including Islip Airport in Long Island, New York, and Somerset and Berkeley, Massachusetts, all at 31 inches (78.7 centimeters). According to preliminary weather service calculations cited by AP, at least 19 weather stations in five states recorded 2 feet (61 centimeters) or more, while Central Park in New York City had more than 19.1 inches (48.5 centimeters) and Philadelphia reached 14 inches (35.6 centimeters).

The storm’s snowfall rate and intensity were tied to a “Goldilocks” temperature range that favored wet, heavy snow, meteorologists said. Shieh said the “Goldilocks situation” meant the temperature was just right so precipitation could fall as snow—adding that warmer conditions would have reduced how much fell as snow, while colder conditions would have limited moisture available to feed the snowfall. Experts also described the storm’s track as close to optimal, saying that slightly different positioning would have changed where the heaviest totals developed by altering access to ocean energy.

Shieh and others also emphasized public caution as crews and residents worked to clear heavy snow. Shieh warned that wet, heavy snow often triggers heart attacks and told people who would be out shoveling to take frequent breaks. “Just a word of caution for those who are going to be out shoveling the snow, that this will be easy to overexert yourself on,” Shieh said, adding, “So take frequent breaks.”

Meteorologists said the storm’s rapid intensification reflected an atmospheric setup driven by contrasts between cold air over land and warmer, moist air over the ocean, along with heat energy from the seas. Masters said the ingredients made it “about as intense as you can get,” and he said the storm’s lowest pressure of 966 millibars would have corresponded to a Category 2 hurricane if it were tropical. Masters said the storm also stood out as a classic in terms of both snowfall rates and overall storm intensity, while meteorologist Louis Uccellini—who had written meteorological textbooks on winter storms—said, “It was just an amazing storm system.”

Experts pointed to larger-scale patterns that set the storm up before it hit, including changes in the polar vortex. MIT’s Judah Cohen said a stretched polar vortex—when ultra-cold air that usually stays near the North Pole pushes further south—started just before the storm and was a factor, and he cited separate prior study findings that these polar vortex stretches are increasing with a warmer Arctic. Another meteorologist, Ryan Maue, said he was “always been fascinated about how Mother Nature figures out how to put all the pieces together in order to maximize the most extreme outcome,” adding that he thought “you could make a pretty good case that this is on par with some of the most impressive blizzards in history.”

In addition to heavy snow, the storm brought thundersnow and lightning—phenomena that Masters said you “only see in the most intense winter storms.” Weather Channel meteorologist Jim Cantore reported live from Plymouth, Massachusetts, when lightning struck nearby, describing it in a scream on camera: “Holy smokes. We got it again baby,” and adding, “In the same place. Unbelievable.” Meteorologist Matthew Cappucci, who grew up in Plymouth and said he yearned for thundersnow, rhapsodized about the electrified event, describing it as “really cool,” and meteorologists said the storm also produced lightning that was visible beyond Plymouth, including to a New York City skyscraper and wind turbines off the Massachusetts coast. Shieh said the weather service did not have reports of thundersnow in New York.

Weather experts also compared the storm’s appearance on satellite imagery to a tightly coordinated system, describing it as fitting “exactly what a nor’easter should look like.” Shieh said it looked “almost too good, like something from a disaster movie,” and he added, “It almost looks like CGI (computer generated image),” as forecasters described how the storm’s features appeared to line up across multiple atmospheric components.