Season's First Significant Snowfall Forecast Fairly Well
Max Snowfall Under Forecast
The first significant snowfall of the 2022-2023 winter season, for at least the western half of the forecast area, is now behind us and it is time to offer a critique of the Eastern Mass Weather forecasting effort.
It is apparent from the comparison below between the Eastern Mass Weather Final Call and actual snowfall totals that the forecast for the majority of the region was very accurate.
However, what is also apparent is that there was in fact one glaring weakness with respect to the forecast map. And that is that the area of maximum snowfall over western Mass and NW Connecticut was positioned slightly too far to the north, but more importantly was too light. A forecast range of 5-9" would have been more representative for this area than the 3-6" forecast range. There is a reason why Eastern Mass Weather did not go quite so heavy with respect to totals in this region.
Trust the Soundings
There was model support for a period of significant snowfall that would accumulate very proficiently throughout much of western New England.
The annotation above is a forecast sounding from the NAM model for Bradley International Airport, which is located in Winsdor Locks, Connecticut. What is very apparent is the well defined "crosshair" signature on the sounding for last night. A cross hair signature refers to when there is ample lift and moisture co located perfectly within the center of the snow growth zone, which is the area between -12 and -18 degrees Celcius that is ideal for the genesis of snow flakes. Immaculately developed dendrite accumulate much more efficiently than poorly developed once, which significantly impacts accumulations. This is why the forecast of 3-6" within that max zone was slightly heaver than some of the model guidance, which forecast no amounts of 6" or greater. However, not all guidance had a signal this emphatic, so the forecast remained relatively conservative. In hindsight this was clearly a mistake, especially since the location of the sounding, Winsdor Locks was not even in the area of heaviest forecast amounts. Thus the forecast soundings over the Berkshires were at least as impressive and likely featured an even more pronounced cross hair signature. It is with this in mind that the forecast obviously
should have been more aggressive in this area.
FINAL GRADE B-