Note: Comparing the boarder of southern PA with northern Maryland, they don’t match.
I trust the snow measurements of 30 to 40 inches in northern Baltimore, Carroll, and Frederick Counties. But in Adams and York Counties in PA the numbers are shown in the upper 20s. This should be 30 to 40 inches per year.
Among the highest totals reaching well over 100 inches, are located in the northwest corner. This is from Lake Effect Snow off of Lake Erie.
The very highest snow zone is near Somerset by Seven Valleys Ski Resort. These mountains enhance the Lake Effect Pattern and reach 152” of snow in an average year.