We are now at a point where the pattern change is coming, we are now at the point that the pattern change is OCCURING. Right in front of our eyes , the weather pattern is turning from warm and benign to cold and stormy, slowly and gradually
What has happened in the stratosphere over the past 1-2 weeks is just amazing. First off it went from historically cold levels to now above average. Number 2 is, the warmest anomalies have shifted from Asia, to now coming into North America! As this continues to drop to the south and east, a trough will start to be carved out over much of the country.
Just remember the 7-10 lag period, so full impacts wont be felt until late December
The MJO is also becoming a significant player, it went through phases 2-3-4 , which was why we started December so warm , it has since circled back into the Circle of death and now it is moving into phase 1
Here are typical impacts, you see 3 – 6 favor warm pattern. But we are now heading into phase 1, that puts convection around the dateline, and arranges the pattern as such, to carve out a nice trough over the east , and cold air is able to flow freely right out of Canada and spill into the eastern US. Theres amazing agreement among models, that it will not only go into phase 1 but STAY in phase 1 for quite some time. This will raise heights in the west , and lead to low heights in the east.
We have already seen a shift to stormier conditions but it’s just the start, we have 2 storms to track , one this weekend and one early to mid-week next week, until then it will be quiet with temperatures around average . These 2 storms will help to pull down the Polar vortex and cold, arctic air . The models have finally begun to pick up on this
Starting out with Sunday, we see the first storm system I was talking about, this storm should not be anything too big, more of a nuisance. A weak area of low pressure will track towards the Great Lakes, it will run into a block in the north Atlantic , transfer its energy to the coast, most likely off of NJ and then move NE , impacting New ENgland more so than us, but still showers are likely Sunday and Monday, even some ice/freezing rain is possible in NE PA , but its the next storm that is catching my eye
I will go more into this in separate blogs in the coming days, but in short, a deep trough is expected to dig into the eastern US , a storm looks to form at the base and this storm could very well be a big one, that comes up the coast , could be a potential winter storm going into next week, but it’s too early for details now.
For the purpose of the pattern change subject , im more interested in what occurs after this
As the pattern change begins to show its face, a very deep trough is carved out over the east, nice ridging building in the west in response , AND we have some blocking (-NAO) to hold this in place, just in time for the holidays. It could be a VERY cold Christmas this year
In this type of pattern, constant storm threats will keep us on our toes
You see that band of clouds from the Pacific right through Mexico? That is the sub tropical jet stream becoming active, due to warm waters in ENSO regions 3.4 and 4 , this is where the stormy part comes into play.
So the pattern change ive been going on and on and on about the last few weeks is now occurring, and its effects will be felt full force , by late December.