"Take unusually warm Atlantic ocean surface temperatures (temperatures are in the 70s off the coast of Virginia), add a cold Arctic outbreak (something we’ll continue to get even as global warming proceeds), mix them together and you get huge amounts of energy and moisture, and monster snowfalls, like we’re about to see here," said Michael Mann, a climate researcher who directs Penn State University's earth systems science center. Mann said the ocean temperature anomalies of 5 to 6 degrees Fahrenheit above average would yield more than a 20% increase of the moisture content of the air overlying that layer of ocean waters. That air, in turn, "is getting entrained into the system to produce the heavy snowfalls," he said in an email to Mashable. Mann said it isn't clear how big of a role climate change might be playing, though, compared to other factors.
But...Ryan Maue, a meteorologist with the private weather firm WeatherBell Analytics, said on Twitter that the process of forming a rapidly intensifying coastal storm involves much more than just higher-than-average sea-surface temperatures.