New Weather Pattern and Storm Chances

If you want more information about the terms used here, check out these websites:

https://climate.ncsu.edu/climate/patterns/nao

https://www.dtn.com/what-is-the-eastern-pacific-oscillation/

Well, there's a new weather pattern. And if you are a snow lover, or just generally a winter lover, it's pretty good for you. We are going to see very cold air, from an arctic outbreak. That part is guaranteed. It's even been confirmed by Phil! However, are we going to see moisture to match it up? If we do, we could see lots of all snow events, and just in general, lots of snow. I will go into more detail at the end of the post.

The European ensemble shows below average air on the weekend of February 5 to February 7. This shows an arctic outbreak leaking from the polar vortex and giving us frigid air.

The Climate Prediction Center(CPC) shows an active storm track for the month of February as a whole, and the whole DMV is in the darkest shade(on the map) of green(this means above-average precipitation). While this doesn't explicitly mean more snow for us, it definitely helps our chances. In terms of temperatures, it shows normal temps (for the entire month, not just one specific part).

 

This image shows much below-average temperatures(high chance of below) for the next 6-10 days. It also shows slightly below-average precipitation for that time period too, but we still have an active storm track.

This image is for the time period of 8-14 days, it shows slightly below-average precipitation and much below-average temperatures.

The EPO(Eastern Pacific Oscillation) is slightly negative at the moment and will remain slightly negative at least for the next ten days. It may turn neutral again, in the next 10-15 days. What does this terminology and weather geek language mean for me? This means that the polar jetstream will be to the north of Alaska, which helps pull down very cold air into North America. A risk of an arctic outbreak during this time period is high. Some models show temperatures in the single digits while the EPO is negative. And the Arctic Oscillation(AO) and North Atlantic Oscillation (NAO) are strongly negative, meaning that storm tracks for the east coast, in general, seem to be good for the next 2 weeks or so. There is the kind of things we need for good snow. And the models do have a bias of underestimating these kinds of patterns, in the sense that they show (blocking) patterns tapering off and breaking down very quickly. Because of this, I wouldn't be surprised to see the models show the NAO remaining negative throughout the whole month.  

There are already many storm chances. There is a chance for some light wintry precipitation on Friday. It's snow to rain event, but it should be light for the most part. I will make an update tomorrow about it, but I don't expect it to be anything to worry about. "We can watch for a light snow or mix at sunrise, followed by rain. This all may end by the end of the day," said Justin Berk.

But there's ANOTHER chance on Sunday. If this threat was to materialize, it would likely be more significant than the precipitation on Friday. The European model has been bullish with this storm, except for the runs today. We have to wait until tomorrow to see if the storm is truly gone, or if it is just a blip. Models will be jumpy this far out. And there is another possibility on Wednesday, but it's so far out that I probably won't be saying anything about it until maybe Sunday-Monday.

There is a slight winter threat for the entire region, for the time period of Sunday-Monday.

The winter storm threat for Friday-Saturday. There is a slight threat for the Piedmont/Shenandoah Valley and Allegheny Front, but no threat for the I-95 Corridor.

Summary: The weather pattern right now is suitable for snow. Very cold air from the Arctic is going to move into North America and just the general USA. The risk of an arctic outbreak has significantly increased due to the cold air. Single digits and lower are possible on some days. Meanwhile, the east coast will have an active storm track, increasing the chances of seeing more storms and just in general more snow. There are already many storm chances for the east coast, and snow chances for the northeast. These patterns may last longer than the models show, perhaps into the rest of February. Winter is far from over. It is just getting started.