Teleconnections Coming Back

Ahh, the other alphabet soup aside from the numerical forecast models. I'm talking NAO, AO, PNA, and EPO, common teleconnection patterns helpful in forecasting behavior of winter patterns.

Despite the impressive cold shots recently, all of the teleconnections I recommend have shown no lasting chill and wintry conditions hanging around.

The Arctic Oscillation (AO), a major player in the winter time, has really been a non factor thus far. Let me explain.

The AO has been in its positive state for a while now, since the beginning of the month. So, one would expect a milder pattern overall for our region. "Not so fast my friend" in the words of Coach Corso.

An unusual or anomalous October snowpack in Siberia and Eurasia as a whole combined with a rather weak polar vortex had contributed to the very cold air here in our region. The disruption to our weather patterns because of the above combination looks like it has finally run its course.

Therefore, we can get a truer, more accurate look at how the AO will now behave over the next few weeks. Used in tandem with the other teleconnections above, cold and snow chances should be more definable, and forecast models might do a little bit better in predicting future outcomes.

Right now...forecasts show:
AO Positive, trending downward to neutral or slightly positive over the next two weeks.

NAO Positive, trending downward to neutral or slightly negative

EPO Positive, trending downward to negative

PNA neutral/negative to remain more negative

Right now, as of today, none of the teleconnections favor a snowy outcome. However, forecasts at least show the NAO and EPO wanting to support a wintry pattern over the next 10 days or so.

But, the AO is still expected to remain positive, and the PNA negative favors a trough west, ridge east scenario. At the very least, a warmer southwest wind will mitigate snow chances unless very cold air is in place. Which we have seen leads to higher ice chances than snow chances.

Remember to keep your eye on the AO index. Some of the best snowfall I have seen here during the last few years have occurred when the AO was negative trending upward.
Right now, we don't have a negative AO yet. A negative EPO helps as well. Team those together and we could be looking at a higher chance for snowfall. Of course, other variables come into play that might blow your mind. If you want to, research the QBO and the MJO to see how their effects may influence our pattern as well.

MS