Reviving this thread because I'm really curious what connection CLF has to northern styles. A lot of the northern styles have connections to each other, so I'd expect CLF to have a connection to one or more of them.
Tong Bei Chuan comes to mind as a northern influence because it has the swinging arm movements and quick-stepping of CLF and influenced many other styles.
https://www.youtube.com/watch?v=JAIo6S4ebe0
Also, anecdotally, my branch of Chen taiji actually incorporates some Tong Bei movements and they feel completely natural to me having done CLF for so long.