Arctic Air To Invade Next Month
The Arctic air will be shut off for the rest of December, giving us a pretty nice mild month. However, don’t get too comfortable with the idea that winter isn’t coming. Winter will arrive soon enough, possibly with a bang. It will certainly seem nasty compared to the gorgeous month that we’ve been having.
For the past month or so, the North American vortex has been stalled up over the Arctic. Looking at the 10MB level temperatures for the past 30 days, you can see this with a large area of very cold temperatures across the extreme northern edges of the North American continent. However, looking at the 10MB temperature charts you can see what could force the vortex down out of the Arctic in January, bringing all of that cold air with it. The feature to keep an eye on here is an area of increased warming over the northern Pacific, which is heading Northeast and is aimed right over the top of the Arctic. This type of pattern has been correlated as a precursor to major Arctic outbreaks into North America. Once this feature tries to force it’s way into the northern Arctic, it will try to muscle out that cold air, pushing it south right over the top of us.
Another sign to look at is the 500 MB heights over the northern hemisphere over the last month or so. Examining a loop of them will show a strong circulation center located very near the North Pole. You will notice that the center has started to shift slightly southeast over the past month or so. What this could end up doing is splitting into a couple smaller circulation centers, which would be a good setup to pump all of that cold air south towards us.
The other thing pointing towards this breakdown of the strong single center is the weakening of the El Nino that has been occurring. The El Nino, which started off weak to begin with, has shown signs of breaking up with the warmest water already west of the International Date Line.
Given, this theory could be completely wrong, but I think that the subtle signs of a change are there. Long-range forecast expert Joe Bastardi has been hinting at this for a little over a month now, and I’m confident enough in the signs now to pass it on to you.
So, enjoy the lovely mild weather while it lasts, because we could really see winter kick into gear to ring in the New Year!
Here are some of the charts that we’ve been discussing:
