Regardless of the amplitude, I expect some cold weather from the SSW most likely in eastern North America and Northern Asia. However, if the predicted SSW is relatively minor with a quick recovery in the stratospheric AO, even possibly becoming strongly positive, would favor a positive tropospheric AO. Then an extended mild to very mild period across the NH mid-latitudes could ensue from late December through much of January. I would expect at some point another PV disruption that would reverse the weather to colder but by then an overall mild winter would be almost a certainty.
Thanks Sebastiaan, bad news for coming winter then.