NAO
The NAO remains negative. The forecast shows it staying negative, at least though the beginning of November. A negative NAO usually locks cold air in place along the East Coast, but other factors, like the MJO can affect this. Anyways, snow/cold lovers want a negative NAO, for a good winter. This winter looks like a relief compared to last year, for those of you who are snow/cold lovers, along the East Coast. This is because the NAO has been primarily through summer, and is likely to continue it's negative trend, through winter.
AO
The AO is also negative. The difference between the NAO, is that the AO has been primarily positive, since summer. The recent dip negative in the beginning of October, might be starting a new trend. The AO is also expected to stay negative though the beginning of November, as the NAO is. What's been weird about the AO is that the past few months it hasn't had a strong correlation with the NAO, while it usually does. The past couple of weeks, however, you can see that the AO has been correlating better with the NAO. The question is if this will last into the winter, for if the AO will continue it's positive trend again. If the AO does happen to continue this recent negative trend, expect Arctic air to plunge south, more often, this winter. If the AO goes positive again for the winter, this would mean more of the time the frigid air will bottle up, well to our north.
PNA
After a quick peak positive, several days ago, the PNA is once again negative. The PNA has been primarily negative, since summer. By early November, there's a chance of the PNA coming positive again. For an even better winter for snow/cold lovers on the East Coast, you want a positive PNA. This would mean ridging in the West. At this point, I don't believe it is very likely that the PNA will be primarily positive, this winter.
