It’s really coming down to intensity and how mid-levels act. Euro is just a bit more organized, mitigating any warm air intrusion beyond the south coast, while the GFS brings that further inland about 30 miles.
Last 5-6 model cycles, the trend has been for a flatter solution. Does not mean that holds or continues. We have seen countless times where we see those last 24-48hrs where things come in more amplified.