Another Snowpacalypse?

Andrew Sullivan —  Jan 26 2015 @ 10:31am

Those of us in the Northeast are watching the beginning of this week’s big blizzard, which will likely inundate 29 million people with up to three feet of snow and 55 mph winds. So far 4,360 flights have been cancelled and NYC’s public transit system could grind to a halt. The National Weather Service is calling the storm “potentially historic”. Harry Enten unpacks that possibility:

New York City is under a blizzard warning for 20 to 30 inches of snow. The biggest snowstorm to ever hit New York dropped 26.9 inches of snow on Feb. 12 and 13, 2006, according to data going back to 1869. The snowy wallop was caused by mesoscale bands that pivoted over the city in the overnight hours. …

If the National Weather Service is dead-on accurate (not a sure thing), the coming blizzard will make it into New York’s top six at a minimum. As long as a foot and a half of snow falls, this storm will be tied for the 10th spot with an 1872 storm none of us was alive to see. Boston is also under a blizzard warning for 20 to 30 inches of snow. According to data dating back to 1935, Boston’s top snowfall, 27.5 inches, occurred during the “President’s Day Storm II” in 2003. It’s quite possible this storm will top it.

But Andrew Freedman warns against that hype:

Don’t pay too much attention to the highest snowfall totals, or the fluctuating numbers. Instead, focus on the likely impacts of the conditions that you are likely to encounter. The big three are heavy snow, strong winds and, if you’re near the coast of New England, coastal flooding. Blizzard conditions require three criteria in order to be met, and they grind transportation of all forms to a standstill while threatening lives through low wind chills. …

Unfortunately, these mesoscale bands are hard to predict less than a few hours in advance. The National Weather Service anticipates several of them to form, including one in the vicinity of the New York City area, but pinpointing exact “jackpot” spots is impossible at this point. That’s why it’s best to prepare for 15 to 30 inches of snow, rather than getting hung up on the likelihood of breaking an all-time record.

Bob Henson breaks down what this means for the region:

Given the projected intensity of this storm, as well as the strong model agreement and the textbook nature of the overall pattern, it seems very plausible to expect widespread snowfalls from Monday night through Tuesday night of 12” to 24” between northern New Jersey and southwest Maine, with some areas in mesoscale bands getting 24” to 36”. Lesser amounts can be expected further to the southwest, with Philadelphia possibly getting a few inches on top of its Monday total. If the system moves more slowly than expected, it could add to the accumulations on the southern and western flank of the vast snow shield. Massive transportation impacts can be expected over the next several days, with reverberations to the air-traffic system nationwide. The high winds and snow could lead to large-scale power outages across New England.

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