Winter 2025 - 2026 final thoughts!

 I've been posting these thoughts on the upcoming winter just about every week or so for the last couple of months. I've been trying to keep you up-to-date on how the pattern is evolving heading into the upcoming winter. Let me know if you like how I went about doing it, And what else you think I could do in the future to make it better.

This is likely going to be my last post on how I think this upcoming winter is generally going to unfold. I will touch on the areas that have been changing slightly that I think are important. I will also place at the end of the post details on how I think the individual parts of our region are going to generally fair. Including the general temperature profiles as well as impacts of the predominant storm tracks and how I think those are going to impact various parts of our region, including an overall feel of the snow amount possibilities for various parts of the region.

Remember seasonal forecast and outlooks can't really show any exact details on what's going to happen week to week. But they do show how the overall pattern looks to unfold. In past outlooks I have gone into perhaps too much detail as far as temperature profiles and how snowfall amounts broke down for several parts of the Northeast and northern Middle Atlantic. Looking back I think that added and caused more confusion than was intended when people were reading the outlooks. So this time I'm going to try to keep things more general.

Snowfall and Arctic ice extent

The snow extinct over Siberia had been growing at a very quick rate. But over the last 7-10 days The snow extent has slowed way down.  Where there's snow in Siberia it is very deep. So there's plenty of cold air locked up over Siberia. The snow extent in the Northwest Territories of Canada is more spotty than it was at this time last year. We still have time to see if the snow extent grows at a quicker pace and moves into the areas that are lacking.

Arctic sea ice extent had been growing quickly over the Arctic Ocean and extends down very close to the north shore of Alaska. But the Bering Strait remains ice free. The ice extent north of Alaska is much further south than we saw last year at this time. Looking at the ice extent in the Chukchi Sea near Russia and into the Bering Strait it's looking about the same as it did at this time last year. Until we can get the ice bridge to build between Russia and North America; the cold air that is bottled up over Siberia will have a tougher time moving into  Alaska and into the Northwest Territories and eventually into the United States.

 Looking at ice extent on the Atlantic side. There is virtually no arctic sea ice. If that remains the case going forward the polar vortex is going to be very weak this year.

Long range anomalies and what it could mean!

Looking at the ECMWF long range temperature anomalies over North America. We can see the low pressure that is in the Northeast Pacific and low pressure sitting over the Southeast US. This is a result of the evolving winter pattern. This setup means we have the jet stream looping up into Alaska over into the Northwest Territories, then it dives down into the northern Rockies and Plains, then heads east ending up arching back up over the  Southeast US and exiting over the Middle Atlantic region.

This is looking out 10-14 days, So we will have to see if it verifies. If it does we could be talking about the possibility of some kind of snowstorm in the Northeast around November 10 to around November 14. But that's not really the point I'm trying to make. This pattern that is setting up is a result of what's going on in the Pacific Ocean. I've been talking about the impacts of these teleconnection patterns for months And I believe this pattern is going to be persistent as we move through winter 2025/2026. And I think it's going to set up the predominant  storm track pattern; that I will go into greater detail about later in this post.

Sea surface temperatures (SST)

We can see the SSTs in the North Pacific are still well above average. I have talked about this area of the pacific a lot (Perhaps too much) and how it's going to impact the jet stream and the overall pattern for the winter. I still think this is going to be the prime driver for the overall winter time pattern.

La Nina:

Over the last several weeks I have been talking about the La Nina quite a bit. There is no change in what I've been saying, that the La Nina is going to be very weak.

I've talked about the El Nino Southern Oscillation  and it's regard to El Nino and La Nina many times. But I just want to touch back on the fact that -0.5 °C and up in Nino region 3.4 is considered a weak la Nina, a moderate La Nina Is considered - 1.0 °C and up, with a strong La Nina considered -1.5 °C. and up.

When we look at the current SST anomalies. We can see that only regions 3.4 into region 3 are barely in weak La Nina thresholds, with the other two regions being considered cold neutral.

Looking at the subsurface temperature anomalies in the eastern equatorial pacific we can see they barely support la Nina conditions.

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Again looking at the subsurface water temperatures. We can see the warmer temperatures are quickly rising towards the surface and will override those cooler surface SSTs as we move forward.

All of these observations support the idea I've been talking about, that this will be a weak La Nina and very short lived. With the La Nina so weak it means that the La Nina is not going to be the main driver of the winter pattern. This will allow other teleconnections to take over the pattern. 

This is going to be weaker than last year's La Nina. So the region should see slightly colder temperatures than we saw last winter. The La Nina is going to be so weak that it is going to create a lot of forecasting challenges as we go through winter.

In these post I've been talking about how the La Nina will be sticking around for the first half into the middle part of the winter. Then we're going to see the La Nina fade to neutral during the second half of this winter. So winter could start out a little earlier than we've seen in the last few winters; becoming active during December, January into around mid February. As the la Nina fades We should still have some lingering winter type events heading into March. But overall  the first 2⁄3 of the winter should be the most Wintry.

The Quasi Biennial Oscillation (QBO) is negative (easterly)

As I said this will increase the odds of a weaker polar vortex, more in the way of high latitude blocking. Along with increased odds of Stratospheric warming events.

Polar Vortex:

The chart shows the ECMWF and 100 ensemble members, showing the zonal mean  winds in the stratosphere at 10HPA. 

The thick blue line is the model ensemble mean, with the thick red line showing the model mean. The thin red lines are the 10th and 90th percentile. For the vortex to be considered very strong you want the thick blue line to be above the thick red line. The closer the thick blue line  is to the top thin red line (90 percentile) , the stronger the vortex is considered to be. On the otherhand, the closer that thick blue line is to the bottom thin red line (10th percentile) the weaker the vortex. So looking at the chart we can see that right now as the vortex is establishing itself, it is fairly strong. But looking out over time we can see that the vortex is forecast to trend weaker. Over these last 6-8 weeks. I've been talking about how the polar vortex will likely be on the weaker side this winter. The model is supporting the observations I've been talking about.

Over the last couple of months I've been talking about the The Pacific Decadal Oscillation,  Tropical Northern Hemisphere (TNH) pattern and other teleconnections, how they would have impacts on the winter pattern. So I really won't go into any more on those. If you want to know what I thought about them you can go back and read about them in the past post.

Details on winter 2025/2026:

Storm Tracks:

All of these things are going to lead to certain types of storm tracks.

Here is a link to a post I did quite some time ago that talked about the types of winter storms we can get here in the Northeast.

We could see a lot of storms this year originate in and around the Texas Panhandle then work their way towards the Tennessee valley.  This would set up the possibility for a primary low to move into the Ohio Valley and lower Great Lakes then do an energy transfer to a new low along or off the Mid-Atlantic coast. This type of storm is called a Miller B Nor'easter.

Miller B Nor'easters are going to be one of the predominant types of storms we see this winter or at least for the first 2⁄3 of the winter. We might not see any Miller A type Nor'easters during the entire winter. But if we do it would most likely be towards the end of the winter when the La Nina is reverting back to a neutral ENSO state.

Another major storm track type we're going to see this year, will be disturbances that will drop down out of the northern Rockies Then move into the central plains and then cut back up into the Great Lakes. These type of storms are called Great Lake cutters. Lake Cutters depending on how much cold air is in place along with the actual storm track, can cause a variety of precipitation types across our region.

The orientation of the North Atlantic Oscillation (NAO)  will be a major determining factor on if a storm will be a Miller B or a Lake Cutter. A negative NAO will increase the odds for a Miller B. Where as a positive NAO will increase the odds for a Lake Cutter.

The other type of storm we could see quite a bit will be the storms that drop out of central Canada down into the United States and then cut towards the Ohio Valley, some of these end up tracking over New York State, back into Canada or over northern New England. But others will end up reforming off the Middle Atlantic Coast. This type of storm is called an Alberta Clipper. These are typically fairly weak but will allow very cold air displaced from up north to move into the region. Most of the region would see light to moderate snow amounts out of these Clippers. But they could end up being major Lake Effect Snow events leeward  of the Great Lakes.

Generally what can we expect for winter 2025/2026.

For this winter we are going to be dealing with a weak La Nina. This means it won't have a lot of influence on our weather over the winter. So other teleconnections like the PNA, QBO , NAO and Arctic oscillation (AO) will be in the driver's seat and overall being a major factor in how the winter will unfold.

The setup that looks to be developing supports the idea that the Northeast and northern Middle Atlantic will  generally be north of the primary storm track this winter. If you're a cold and snow lover this is a good thing. As this would place us on the  colder side of the storm track, increasing the odds for more snow events.

The vast majority of Pennsylvania and much of Maryland and Delaware. As well as New Jersey the eastern half of New York State and all of New England. Can expect temperatures to generally be average to below average. Generally precipitation will end up above average over the winter. Y'all can expect at least some snowstorms that are significant, while other events will range from smaller snow storms. But  depending on the amount of cold air in place and the individual storm tracks, there will be the chance for mix and ice and possibly even rain events at times 

For southern Maryland, southern Delaware, far southern New Jersey, Delmarva and the rest of the Middle Atlantic region, y'all will be close to or on the warm side of the storm track. So your overall temperatures look to be average to above average. Due to this you look to see above average precipitation through the winter; with a predominance of your storms being either rain or mix events, along with a chance for more than a few thunderstorms.

A general breakdown for the major cities along and near the I-95 corridor.

Washington DC, Baltimore over to Atlantic city  look to be under the main storm track. As the storms evolve and redevelop along the coast, y'all could end up dealing with a lot of warm air mixing into this region. This would mean you would see a lot of mixed events That result in the possibility of little snowfall. Generally You should see around average temperatures with average to below average snowfall.

For Philadelphia, Newark, New York City, Providence up through Boston. This area should end up with some mixed events, But you will have a greater chance for snow events as well,  some of these snow events could be significant. This area also looks to see generally average temperatures, with average to above average snowfall being a good possibility.

What about the rest of the region?

Lake effect snow is looking like it could be a big deal this year in the snowbelts. Overall this area should see below average temperatures. Last winter saw well above average to record snowfall amounts across many areas downwind of Lake Ontario and Lake Erie. Winter 2025/2026 looks to be more of the same, with Northwest Pennsylvania, Western half of New York State into northern New York State seeing well above average to in some cases epic snow amounts throughout this winter.

The bottom line is, while this winter won't end up being historic for much of the Northeast and Middle Atlantic. There is a lot of potential in the pattern to end up with a generally decent winter across a large part of the region.

That's it please tell me what you think and how you feel my approach went involving winter 2025/2026.