I went back to the historical data from our weather station there and for the last four years, the last freeze was:
2017 - 5/12
2018 - 5/11
2019 - 4/16
2020 - 5/11
It’s about four to six weeks between locations I’d say. While trees are starting to leaf out in late April/early May, they aren’t fully leafed until the last week of May. It’s really quite stark driving from Frostburg crossing into Garrett County in early/mid May.