Don't think of centuries as culturally isolated from one another. It's just a convenient way to tell time, nothing more. So the 14th century is not a cohesive unit of time that has cultural similarity within itself, and thus distinguishes itself from the 13th or 15th centuries. Rather, cultural changes happen on their own time, and often happen over the span of decades, not centuries. That was a really long way for me to say that styles change rapidly within one century and are not the same or even similar throughout
Anyways... for the beginning of the 14th century you're looking at a long ankle-length surcoat like this:
In general, during the middle of the century, you're looking at the surcoat getting shorter (just above knee length) like these:
By the later parts of the 14th century, the Germans, much like the French and English have gone to the Jupon, which is still a 'surcoat' but it's very tightly fitted and very short (ignore the cape he has on):
The 'Cyclas' style surcoat, or the short in the front, long in the back style doesn't really seem to be a thing in Germany, but it was definitely big in England during the 1340's.