Some on here famously wondered if a Dec 2008 or Feb 2019 was still possible before they happened...
Gotta remember that January 1950 was incredibly anomalous not only for that era, but even going back to the 1800s no month came close for that combo of snow/cold for a very long time.
Once the cold onshore flow is snow at sea level then the totals can really pile up. We saw the models try to accumulate snow in that scenario last winter but it wasn't realistic.