What's ECMWF and GFS?
blonde here...LOL, and it's early
The ECMWF is a European weather model. The GFS is the primary American weather model, which runs 4 times a day, rather than twice as the ECMWF.
The GFS is know for "flopping around" (changing its solution) often.
A large number of private meteorologists consider the EC far superior to the GFS, though I think that superiority may be somewhat overblown.