On March 14th, 2017 a major winter storm, blizzard for some locals ,crushed parts of the Northeast USA. While the big cities, such as Philly, NYC, Boston missed out on the tremendous snowfall, that wasn’t the case across the interior where up to to 2-3+ feet accumulated from parts of the Poconos, Catskills , Central New York State over to the Green Mountains of Vermont. Wind gusts to Hurricane Force slammed the coastline of Massachusetts.

There were a few jackpot totals of over 40 inches of snowfall inbetween roughly Binghamton & Utica, NY. Speaking about Binghamton: this was the most snowfall in a 24-hour period ever as 31.3 inches was reported at the airport. Oddly, enough that was about the total snowfall for the entire season last year winter (2015-2016).

Heavy snowfall/blizzard conditions with 1-2 feet were predicted in the NYC area, but it did not come to fruition, as about 8 inches fell in Central Park with a thick layer of sleet atop that snow.

What happened in NYC?
The most reliable computer model output, only 12 to 24 hours prior to the onset of the winter storm, had the mixed precipitation band(sleet/freezing rain, rain) by the New Jersey shoreline or about Belmar vicinity to the Long Island area, and with that input, meteorologists had more snowfall for NYC and much less mixed precipitation, or at least a later onset time for the mixture to occur. However, the final outcome of what’s referred to as a “warm tongue” or where warmer air aloft(few thousand feet above surface) changes the snow to sleet and/or freezing rain, or even plain rain, actually verified some 40 miles further north & west than originally forecasted. Therefore, this mixture worked into the metro NYC area by daybreak (quicker than forecast) with just some alternating snowfall into the afternoon as that was the end of the heavy snowfall accumulation for the day. Very often the case, once you hear those first pings of sleet, it’s awfully hard to get back to all snowfall.

This warm tongue only made it to the nearby suburbs of NYC since many areas from northern NJ to Rockland county into interior CT, still received at least one foot of snow and just a 20 mile difference resulted in a remarkable 12 inch difference of accumulation as for example, a total of 8 inches in Yonkers (Westchester) to 20 inches in Stony Point, Rockland County.

As for the historic snowfall in upstate New York particularly Central New York State, we believe it was a one, two punch! Very deep and strong coastal low pressure (main culprit) was assisted by an upper level low pressure in the Great Lakes, and this feature aided and/or prolonged the deep vertical ascent for heavy snowfall adding insult to injury (as for excessive snowfall). To be less technical, low pressure creates rising air/ascent, resulting in precipitation, while high pressure provides subsidence and drying.

A lesson learned from this winter storm is that no computer model is perfect and even regarded as one of the top performers, known as the “European” don’t always nail it. I do give credit to the forecast models with the correct timing, overall strength of the system as that was on target several days prior. It was the thermal profiles that was off (not terribly enough on a grand scale) but just enough to preclude NYC /Boston in the remarkable snow totals.

With this storm in the books and now Spring here, I still find it rather odd to see this much snow /ice on ground considering the longer March days and stronger sun angle. Ironically, this will go down as the longest stretch of time with snow on ground surfaces in the NYC area… all winter. Typically that would be more reserved for January or February, not after March 15th!

At least one positive aspect from this event is that no complaints on the upstate reservoir levels being low this spring!

Met BZ

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