Winter Cloud Tops

In a previous article, "O. Sami Saydjari" said:
What are the typical cloud tops at for winter flying--if there is any
such thing as typical. I would venture to guess that tops are below
10,000 ft 80% of the time. I am talking here about mid-west and east

I'm curious as to the answer to that as well, especially as regarding lake
effect snow off the Great Lakes.


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