The Pennsylvania State Climatologist works out of Penn State University, and publishes monthly updates or blurbs on significant weather events during that time. Their website is being worked on at the moment, but has plenty of information about past weather, current snowfall, and significant rain events.
One page has the top 30 twenty-four rainfall events across 10 stations. State College and Johnstown are both listed on this page, and show a significant rain event at the end of September/beginning of October 2010 associated with the remnants of Nichole. Johnstown airport received 2.73" rain on September 30th and State College saw 3.21" rain on October 1st.
Their website is one that you can spend an evening exploring, but there is some work being done on the site so you might find yourself clicking the back button every once in a while.
If you're moving to or are reading this in another state, the American Association of State Climatologists serves as a type of hub for all the climate offices in the U.S. Some states do not have a "Recognized State Climate Office," but you can still visit those pages or the regional page if the state does not have an office at all. Rhode Island and Tennessee are two states without state climate offices.