Sick White Pine Trees
I have a numerous white pine trees on my property near Centre Hall. Last year I noticed one tree with groups of needles (on the ends of the branches) that turned brown. This is very different in appearance from the annual needle drop. This year the first tree is looking much worse and other trees in the line now seem to be impacted. I have attached photos to better demonstrate what I am trying to describe.
White pines are very sensitive to their environment. There is a condition called white pine decline that matches your description. Here is a complete description of this condition by Vicki Motz from eXtension.
White pines also get fungal diseases that cause them to drop their needles. If you look closely and see lesions in current-year needles beginning as spots that develop into brown and yellow bands that continue to expand, you should take a sample to your local Penn State Extension for analysis and recommended action.