Below is a look at how history might suggest the midweek storm would unfold for New England, but for a look at my complete write-up from the here and now, click here.
Although every weather situation is different, and therefore each outcome unique, I believe there is always value in looking to history. After all, through an unbiased examination of history, we can find similar patterns, and learn from what transpired in those situations in the past. We can find these patterns in weather, human behavior, the economy and more - truly, our past foretells our future, and the question at hand is: have we learned from our past, and can we adapt for the inherent fact that even similar situations are not exact replicas.
So...when making a forecast, one regular stop for me is to determine the outcome of similar previous storms. I don't always share these comparisons, as there is danger in singling out specific storms, and I surely don't base forecasts entirely on these comparisons. That said, it's interesting to note that when matched against history, mean snowfall amounts in New England with storms similar to our midweek storm were on the order of four to six inches for the vast majority of Central and Southern New England. That said, a lot of detail can be lost in the "mean," or average; for instance, some similar storms brought nothing, others over 18" of snow. Through all of this garble, we can derive probabilities - based solely on history and similar storms, here are is the chances of various accumulations verifying somewhere in Central and Southern New England:
- 2" of snow: 80%
- 4" of snow: 50%
- 6" of snow: 45%
- 8" of snow: 40%
- 12" of snow: 30%
- 18" of snow: 15%
- 24" of snow: less than 10%
Putting all of this together, it becomes clear that an event with average amounts of greater than 8" is far less likely - not impossible, but sharply less likely - than an event of less than 8" of snow. Historically, the greatest amounts were found in the higher terrain of Southern Vermont, Western MA and Southwest NH, with a secondary, lesser maximum in the Worcester Hills. Interestingly, another secondary maximum shows up over Southeast MA and Cape Cod, likely owing to the storms that produced heaviest precipitation there while sliding southeast.
Though this won't be the final forecast, it's always helpful to see where history suggests we'll fall.