One other symptom I believe we’re seeing of a warm Atlantic has played out in the MA and NE over the last week. They got a perfect track coastal storm and, other than a few bands where rates overcame BL temps, most areas struggled to accumulate. Boston was mostly rain from a storm traveling south of the 40/70 benchmark in mid February! You cannot tell me that the sst anomaly along the east coast wasn’t at least partly to blame for the outcome of that system in areas where the flow came off the water. Now for the flip side- this clipper that just went through. Without any coastal influences and no coastal flow, it was able to produce a stripe of snow from 8-14” from the Midwest to the coast. In fact, even areas outside the band were able to accumulate efficiently. I know the DC area got screwed but that was mostly due to the storm track and lack of precip in that area.
My point is this: both of those were borderline BL temp setups and one was far more efficient at producing snow than the other. Down here, EVERY event just about is borderline, and given the same setup as they experienced, that 2-3 degree coastal influence due to excessively warm sst can be the difference between what, given normal sst, would be a winter storm vs a rainstorm. Just pretty wild to see in many regards a clipper outperform a juiced up coastal in prime climo in NE