Pattern Change for Northern Hemisphere Early-Mid December

There is high confidence in a significant pattern change happening for North America, bringing a much colder airmass to the central and eastern US. In this thread, I will explain the specifics of why.

Firstly, the storm on the 28th will bring in the Arctic airmass after it moves out, which will be coming from Siberia due to the -WPO/-EPO. This is accompanied by ridging in western NA building due to an equatorial jet extension.

Next, let's focus more on Asia. An +EAMT event is predicted, which indicates a jet extension, and we can see this from the AAM spiking. This jet will also be more equatorial rather than poleward, so as a result of this, the jet will speed up into the north-central Pacific, with lower heights expected downstream from Japan to north of HI. 

Due to the equatorial shift -> extension, not only is downstream ridging built over western North America, but blocking is set up north of the jet across the far north NPAC, forcing strong blocking over the high latitudes; Siberia/Asia to Alaska/N America(-WPO/-EPO), which forces an arctic airmass into the mid-latitudes of North America. Furthermore, because of the western ridge, it specifically goes into the central-eastern US.

Looking at the MJO, the MJO is very weak and slow-moving over the MC, showing that teleconnections are overriding the MJO. The jet is in the right place; with the +AAM being strong enough to extend the jet to a favorable position but not strong enough to overextend the jet. This, along with the slow-moving and weak MJO is good for maintaining this pattern in general, though I'd expect a small reset at some point as we reload again(mid December?).

This pattern is also going to cool the warm pool off of Japan and warm the GOA and West Coast, so we should expect to see the PDO rise. It will not flip this winter but we should see some significant rises given how sustained this pattern looks to be.

As for the NATL, although we have an -NAO, I don't expect anything sustained in response to the wave reflection in the NPAC(-EPO); it will probably be replaced by a Hudson Bay vortex. In my opinion, while we probably will have -NAO at times in this pattern, it will be happening because of wavebreaking/intensifying 50/50 lows - so more shortlived. Generally, I'd favor a neutral NAO for the upcoming time period, but I'd assume after the next reload that we start seeing more HB vortex. 

After the Arctic airmass moves in, the eastern US will have significantly well below normal temperatures. A tall western ridge will create split flow, with the NS going through the northern portion of the ridge and the southern stream undercutting the ridge. However, the first part the pattern will be cold and dry as the baroclinic zone gets suppressed well to the south and there isn't any room for NS waves to amplify or southern stream disturbances to bring moisture up. This holds from the very start to ~Dec 5-7, but this will set a very favorable and cold antecedent airmass in place for when the trough lets up a bit and there's more legroom for waves to properly amplify, with a taller/stronger +PNA that looks to connect more with the WPO/EPO ridge, providing a more amped pattern. I'd say Dec 5 to the start of mid-Dec is the most viable time period for snow in the mid-Atlantic/Northeast.

The Alaskan ridge will retrograde westward into Siberia eventually, which will retract the jet(reload), but with the continuing +AAM, I doubt we switch to a canonical Nina pattern rather than just a small reset. Thus, the Aleutian trough will back away eventually as it loses momentum from this week's +EAMT/jet extension, but I'd assume we get the AK ridge to move poleward again with another small jet extension that brings cold air eastward again. MJO will enter WPAC which will regenerate westerly momentum again.

Overall, a cold pattern will take place for the central-eastern US, and will have legs for most of December due to the favorable atmospheric conditions in place.

Winter Outlook 2023-24

full 36 page read/analysis: https://tinyurl.com/223zv9ec

Analogs:

Top ENSO analogs: 1957/1965/1991*

MEI Analogs: 1986/2009

Top Pacific Analogs: 1965/1972/1995

Polar Analogs: 1957/1965/1987/2009

EMI/Orientation Analogs: 1982/1991*/2015

1957/1965/1972/1987/2009 are my highest weighted analogs

DJF Weighted Temp/Precip Composite

The ENSO will likely end up as a basin-wide(with more of a western lean like 1957/65 as Nino 4 warms and Nino 1+2 cools), with periods of Modoki forcing. I do not think that this is a wall to wall cold and snowy winter, but rather bouts of favorable patterns/timeframes, with most of the bulk being in the second half of the winter(Feb). I think we overall end up N-slightly AN for the winter, with Feb being BN, and Dec slightly AN, with Jan being around N. There’s too much variability and unpredictability to pinpoint specific temp anomalies for those specific months, but I still think we overall end up N-slightly AN.

Snowfall:
 

The range this winter is extremely large, with the maximum high-end potential being a top 5 winter or another horrible, low-snow winter. Strong+ ninos tend to be very boom or bust winters. With the exception of 1994/95, every analog year I had was either under 10” or over 30”. As I mentioned before, the main thing that will determine the fate of this winter is the polar domain. With the -QBO/++AMO, as well as bouts of favorable forcing setting up at times, the polar domain is looking good for this winter. While we have a -PDO, the strong El Nino will win out and override the state. The warmest anomalies being over and east of the dateline is a very good thing and very different to the forcing we’ve been seeing over the past few years. The active STJ should provide us with plenty of storm opportunities and ample moisture, snow or rain regardless. Thus, this is also the best chance since 2016 for a HECS/KU. Even if we don’t get a KU, the active STJ provides many opportunities for multiple SECS/MECS. 

That is why I went well AN for snowfall for this year. I doubt we see a near-normal year; either much BN or much AN. There is a lot of potential this year, and as of now, things seem to be looking good. The warm Atlantic will also provide extra moisture for storms. Going around the mid-range this year for snowfall doesn’t appear to be a good idea. This year definitely won’t be that cold overall, but we don’t need extreme back-to-back cold anomalies to get snowfall. All we need is one wave to time up right. With a Nino, the Pacific shouldn’t be too much of a problem this year. ENSO influences PDO, not the other way around; especially at this strength. 

I also went for a more N/S gradient in my map than a W/E gradient. The big nino years here had a more north-south orientation for the gradient than a west-east(obviously being more west still favors more). Although we’ll see some CAD storms, especially earlier in the season, I don’t think we’re going to be seeing too many of them overall. I think the PNA this year will average out to be neutral-slightly positive, with the western ridge flexing at times, increasing in frequency as the winter progresses. This should favor more Miller A/C type storms, which generally aren’t as W/E gradient oriented. 

Given how things appear to be progressing, and the best-looking year in several years, I believe that going bullish on a high snowfall winter is the right decision to make.

Summary:
 

Overall, I am sold for a well AN snowfall winter for the Mid-Atlantic and SE, and BN for NE. The strong Nino and STJ should heavily favor the MA/SE, and lead to suppression issues not much further north. ++AMO favors further S blocking, which in turn favors a further southern displaced track. Along with the STJ and other factors, the main focus of this winter on the EC will likely be the MA.

 

December, although not favored by Nino climatology, doesn’t look that bad anymore, and might be AN in snowfall, with a -NAO setting up for the early part of the month, and forcing returning to favorable phases by mid-late month. Although I expect it to still end up slightly AN, there’s definitely the possibility of the month ending up near normal. We should have a generally transient warmup in mid-Dec before returning to a favorable period later in the month. Although climo before mid-Dec is at best dubious, it is certainly possible to get some events, especially with the pattern setting up. For the month, I could see us getting a few minor events, and maybe even a moderate event. The very end of the month seems to be the best time period for something. I do not expect the PNA to be overall positive, but we could get a few transient +PNA flexes, along with HL blocking around this time. HL blocking setting up in December; and an -NAO is a very good sign for the winter and for higher-magnitude blocks to set up later in the winter. 

 

January looks to be alright, with the favorable forcing from late Dec continuing into the early part of the month. As stated previously, this month will generally be transitional, but the pattern at the start of the month will remain favorable. Thus, after early Jan, it appears to be quiet for a bit, until the end of Jan, where the pattern will become favorable again and continue into Feb. This is also when peak climo starts. Again we might see some +PNA flexes, but it should remain generally variable throughout the month. We should end up around N for this month temp-wise, and snowfall.

 

February will easily be the best part of this winter, with everything lining up: frequent +PNA flexes, favorable forcing setting up, HL blocking, active STJ, and overall peak climo should make Feb exciting. This isn’t too much of a surprise though, as Nino climatology heavily is backloaded and protrudes Feb as the coldest, snowiest month. We should definitely end up BN for this month in temps and AN in snowfall.

 

As for indices:

 

• PDO: slightly BN; -0.4 to -0.9

• AO: slightly BN; -0.2 to -0.5

• PNA: N-slightly AN; -0.1 to +0.3

• NAO: N; -0.2 to +0.2

• ENSO peak: 1.7-2.0(under super)

• ENSO Orientation: West-Tilted Basin-Wide
  
   

overall, should be a fun winter to track w/ the first real nino since 2015

 

Cold Front Moving Through Saturday for Average Fall Temps

Good evening! This week, and so far October in general has been really muggy, and unseasonably hot for fall! Fortunately, a break from the hot weather is coming soon. As a storm on Saturday moves through our region, a cold front moves behind it. By the time you wake up on Sunday, it won't be hot/muggy anymore outside. This will last for a bit too. Expect highs to be in the 60s and lows to be in the 40s/50s during this time period.

You can see around Saturday night/Early Sunday morning the blue/purple circle moves through our area. This is the cold front pushing in afterthe storm moves through our area. And it lasts for a couple of days too.

 

There really isn't much to say about this cold front other than that it will start to feel seasonal soon. However, long range models do suggest a stratospheric warming event around the end of October/start of November, bringing us some cold air(below-average temps) from the polar vortex. That is something to watch in the near future. Once November starts, all of the news stations will start to make their winter forecasts. This winter is going to be an interesting one.

Mid-March Weather Pattern Update

During La Nina winters, something usually comes up in March that is wintry-weather related, even if the winter that year has so far been not so good for winter weather(in terms of amount). Take the winter of 2016-17 and 2017-18 for example! Our snowiest days those years were in March. Well, we have something coming up in mid-March! This week will be the warmest week we will have SO FAR this year, but then it starts to get colder and temps will drop after Friday afternoon.

The CPC has below-average temps for the entire DMV during the time period of 3/14 - 3/20 and has a strong chance for below-average temps(>50%), and for the below-average temps to be more stronger(colder). The southeast ridge(warm air) seems to be losing. This outlook reflects the negative EPO, which is one of the most driving teleconnections in the weather. The negative EPO, as you might have guessed, brings a colder solution to the eastern US.

The CPC also predicts above-average precipitation for the entire region(except for western Maryland but that area is still in the "above-average precipitation" area), and it's not a small chance either(moderate to strong chance of more precip than normal, and for that quantity of precip to be more). This increases our chances of snow with the cold air in place and an active storm track, the chances for storms to produce wintry precipitation increase.

EPS(European Ensemble):

Now, the reason I zoomed it out so much to include all of North America is to focus mainly on Alaska and to see how it affects us. You see the orange in Alaska moving through there? That's a sign of a ridge forming there. What does that mean for us in the Mid-Atlantic and Northeast? It means that around next weekend, a negative EPO will form, pushing down cold air from the Arctic to us. This will cause a cold week from March 15-20, but models are trying to break it down by the end of that time period. Even then, I wouldn't be surprised if the models keep trying to delay the possible date of the -EPO breakdown further, since they have been doing that this year.

Also, today morning, Judah Cohen tweeted that the message from the American and Canadian ensembles is to not put the snow removal tools away yet and that starting next week, there is an increasing chance for snow. The more north you are, the higher chance you will see snow. He also shared some images that I will show.

This is the GEFS(American ensemble) for 3/13-3/17. It shows blue(the darker the blue, the higher the chances for snow and cold temps are, the darker the red, the lower the chances for snow and cold temps are) awfully close to MoCo, and for the western and NW suburbs of the DMV, the blue(more snow and colder temps) is present there!

This is the GEFS, and it shows blue for a lot of central and northern Maryland, with the highest chances of snow(darker blue) in the NE suburbs of the DMV. This is for the time period of 3/18-3/22.

This is the GEPS(Canadian ensemble) for the time period of 3/13-3/17 (same scale as the GEFS, darker blue = more snow and cold temps, darker red = higher temps and less snow). It shows blue for almost all of our county, and for the DMV, in our northern areas(not favoring west or east). It's mostly light blue, but it is still a good sign for snow lovers.

This is the GEPS for the time period of 3/18-3/23. It has blue for a lot of Virginia and Maryland, and the areas in the DMV that are the most into the blue would be our western and northwestern suburbs. This also includes the mountains!

As you can see, the ensembles are starting to have the confidence for more snow and colder temps for all of the region, and especially for our northern and western suburbs. This could be winter's last shot, but winter could extend all the way into April, and maybe even May to a certain extent. Winter isn't over yet as I think I can push above-average snowfall this year; all I need is 1.1 or more inches. We already have some good systems to track next week. For snow lovers, there's one last hope. This week is going to be very warm though. Highs will reach well into the 60's, and models are showing temps even getting into the 70's in some areas! Spring isn't here just yet though.

Spring is Coming... but Winter is Still Here...

Yesterday, we had very mild and nice weather. It felt like spring. And with temps expected to be warmer than the rest of February, some people are going under the unfortunately wrong thought that winter is mostly wrapped up. I know I already made a post about how winter wasn't over, and I still stand by that. I will be giving more data from more experts as well. 

Winter really had fun toying with us in February, cause it was the first time since 2015 that we had below-average temperatures. We also had 9 storms. However, we didn't really get that much snow from them. In theory, they should have gotten our snow totals much above average. La Nina doesn't really work out for us though, but this winter was still a good season, primarily for our northern suburbs and more inland areas. And we still have March to go.

Now March... you've heard the saying "March comes in like a lion, and out like a lamb". Yeah no, it will probably stay as a lion for a good part of the month. The European ensemble is showing some very interesting connections that need to be watched.

Credit to Justin Weather for this image

The AO is positive, except for March 5 alone, where it's neutral/slightly negative.  This is not good for snow, however, the time period of March 5-10 needs to be watched closely. Pattern fluctuations during this time period are possible, and even somewhat likely! Justin Berk says that "he does not see anything major before March 12 in the arctic oscillation", which is fair, considering that it's positive. However, it still needs to be watched very closely.

Credit to Justin Berk(Justin Weather) for this image

The NAO is slightly negative for the start of March up to March 6th, and that pattern supports snow. But from March 5-10, we need to watch the NAO. It goes strongly positive and then starts to go down to slightly negative/neutral. This is what I meant by pattern fluctuations. We need to watch early - mid-March, cause patterns are going to keep fluctuating rapidly.

Tweet from Judah Cohen:

Dr. Judah Cohen, an expert on the Arctic and how it can affect the weather here, has pointed out that the GFS is showing another arctic buildup during the 2nd week of March, where Greenland blocking returns and increases the risk for colder weather, including snowfall for Europe, and how it could possibly expand to us in the eastern US. Another person in the comments of this tweet(Michael Solomonides) stated that this pattern is also starting to show up on the long-range runs of the European model

Credit to Justin Berk

And just to add insult to injury, do you see the temperature fluctuations during early March. From down to up, and from up to down... There is a consistent cold after March 1st, and the trend seems to be going colder(European Model for Baltimore).

And you know how I was talking about La Nina? During La Nina winters, there's usually something that comes in March, even if the winter so far wasn't that great. During the winters of 2016-17 and 2017-18, IAD(airport closest to MoCo) had its snowiest March, due to Winter Storm Stella(2017) and Winter Storm Toby(2018). I don't think our snowiest month will be March, even with that being said, but the point is March cannot be underestimated. And for people who have lived here for a long time, I think you know that already. During the superstorm of March 1993, IAD measured 14.1 inches of snow! Heavy snow fell while temps were marginal(33-35)! 3 FEET of snow fell in Westminster, in Carroll County during that storm! March 2014 was the snowiest March since 1963 for IAD, where 19.3 inches of snow fell. All I want to say is that winter is not out of the game.

Is Winter Over Yet?

Next week, after Monday, there will be a warmup, with highs in the 50's and might even reach around 60! And if you are more on the technical side, we will also get out of the stormy pattern that's been hitting us constantly with winter storms. And now, some people are saying things like "Winter is fading out", or "Spring is coming in fast." 

While I would like mild temperatures and warm weather, the answer is no. Winter is not over, and won't be any time soon. Tomorrow and Sunday are going to frigid; likely the coldest air of the season. Lows will drop into the teens and highs will struggle to get above freezing. A massive refreeze is coming, and you should be prepared for icy spots tomorrow. Wind chills will make it feel 10-15 degrees colder than it is, and will be in the teens all the way into the single digits at times.

Although the warmup will happen, and from there, temps won't be too cold, we have a good pattern coming into March; one that we haven't had this winter: a negative NAO and a positive PNA. Early March is going to interesting, and we will likely have many threats. Those are all good patterns for snowstorms. I think we will see at least another 1-2 inches of snow areawide(maybe not DC though) before this winter is actually done. You can quote me on that if it doesn't happen.

The European ensemble shows a positive PNA for early March. This makes atmospheric and surface temperatures below average. Research shows that positive PNA produces more winter weather events, and the number of them is above average. 

The European ensemble shows a negative NAO for early March. A negative NAO means colder temperatures for Northern America, and they linger. It sets up a blocking pattern for the Atlantic. During the winter of 2009-2010, the NAO was strongly negative during that time, which caused dumps of snow and frigid weather.

We already have 2 threats to watch in the upcoming week: one on Monday and another one next Friday. Monday looks like snow to a cold rain event, but this event should generally be small. Friday is too far out to discuss details, for now, let's just say it's an all rain event because the models have been so bad this year. We have a little bit of agreement for some wintry precipitation Friday, so I will watch it closely. Expect it to be a bust if it materializes, as with almost every winter storm this year.

The NWS shows a slight threat of a winter storm for Monday-Tuesday.

In conclusion, winter is not over. Although we will see a warmup midweek, our pattern is favorable for early March, and a positive PNA has not happened in this winter; and a positive PNA is favorable for snow and colder temps. Tomorrow and Sunday will likely be the coldest temps of the year, with temps in the teens and wind chills in the single digits at times. We have threats on Monday and next Friday, Monday seems to be a snow-rain event, but Friday is too far out to discuss details. I hope you are ready for more winter, cause it's not going anywhere soon.

Saturday Storm Update and Some Other Storm News

 Well, snow lovers love a good snowstorm. Others hate it. But, the type of storm coming up on Saturday is something both snow lovers and snow haters hate: an ice storm. Sure, a little bit of freezing rain that causes a glaze on surfaces is pretty, and not much is done. But once you get over a quarter inch, that's where instead of looking pretty, it becomes devastating and catastrophic, with injuries and even sometimes fatalities occurring. We have 3 storm threats in the next week or so. The first one is on Saturday. The second one is on Monday to Tuesday(may linger onto Wednesday) and the third one is on Friday to Saturday. Thankfully(I say that because it's ice, not snow), this storm does seems to have less moisture than the next 2 ones. However, as it stands, the next two ones look like ice storms too. And just to show you how active this pattern is, let me show you something.

Well, there's something you don't see everyday! Winter storm threats for the northern regions for the entire time period the NWS' "Winter Storm Threat" covers! I have literally never seen this before. This is insane! There is an enhanced threat for the entire region I forecast for, on Saturday(high confidence, "low" impact). A lot can change though. Besides the crazy pattern that can easily be compared to the historical, record-breaking(in terms of snowfall) winter of 2009-2010, let's focus on our first threat: Saturday. Watches have been issued JUST south of us for Saturday's threat. I assume they will be extended northwest soon enough. You know it's a little bit wacky when D.C is the most northern zone in a watch; or any alert for that matter!

European Model:

The European model shows moderate-heavy freezing rain falling the whole time this storm, with rain far south of our county and snow far north of the county. It doesn't show any sleet either. It shows the system starting on Saturday evening/night and shows it getting out of here by Sunday.

Now, the European model has been very bullish with the ice, showing over a HALF inch for the entire county(image courtesy of Justin Weather) Once there is over a half-inch of ice, widespread power outages occur, and severe tree and power line damage is done. Not to mention travel is literally impossible. Although this is a lot, even half of this would cause major issues. The European does not seem to be backing off. Temps will be much below freezing on the ground the entire time, so any ice should accumulate.

GFS:

The GFS mainly shows scattered freezing rain showers instead of an ice storm. It shows them lasting from late Saturday night and shows them stopping after very early Monday morning(1-3 AM Monday).

The GFS shows much less ice than the European model, with only 0.05 to 0.15 inches of ice(Phew!). This will still cause disruptions though.

CMC:

The CMC shows the storm starting as an icy mix(sleet and freezing rain) before turning over to heavy freezing rain and then eventually going off to the ocean. More sleet would lessen the impacts of this storm, as sleet is less disruptive than freezing rain.

The CMC shows 0.3 inches - 0.5 inches of total accumulated precipitation. If most of this is ice, we could have a pretty disruptive problem on our hands.

Temps on the ground will be below freezing the entire time. Plus with the snowpack we have right now, ice will accumulate on any untreated surface, and will wash away pre-treatments if not put out regularly. This freezing rain shouldn't melt completely once the storm is done, it should be staying here for a while.  I won't be showing the other storms until this storm is done. Why? This storm will set up the next storm from Tuesday to Wednesday. And the Tuesday to Wednesday storm WILL set up the next Friday - Saturday storm. And besides, we are very far out. I don't think it's a good time to talk about them, because they will be changing rapidly. They could be major winter storms for us(the storms next week). They should be either snow or ice due to an arctic high and cold air in place. The latest storm(this Saturday) does seem to be trending towards being weaker, which is good. After the next 2 weeks, winter does seem to be weakening its grip a bit(we could still see some good snow after the next 2 weeks). Travel will be very dicey and difficult; impossible at times on Saturday evening - Sunday. Please avoid any unneeded travel unless absolutely necessary, and make sure to stay slow and careful on the roads; don't make any sudden movements or breaking. What appears to be wet surfaces is most likely ice. I will release another call tomorrow and my final call on Saturday.

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.

It's going to get much colder...

 As you might have heard already, we are in a favorable pattern for snow. However, we still haven't gotten any snow at all, even in the favorable pattern for snow. However, this means that if we get a good potential for a good storm, the chances of it happening increase. But, as you read by the title, its going to get colder. 

As you can see by the image above, there is indeed going to be colder temperatures in the next 6-10 days, and chances are leaning towards being colder than normal. We have sufficient cold air for the time period of 1-22-2021 to 1-26-2021. This means that any precip potential could easily give us a snowstorm. But that's not all.

Now this one shows a much stronger and higher chance for cold air! This means that any precipitation in the period of 01-24-2021 to 01-30-2021 is probably going to be snow. Expect temperatures in this period to be much, much colder than the temperatures we have now. But there's even more. 

Now, this thing really puts a good scenario for snow in our area. Why? Precipitation(not snow, just all precipitation in general), is supposed to be above average during the time period of 01-24-2021 to 01-30-2021. With the much colder air, this could easily bring us some snow. For the first image I showed you, the precipitation is supposed to be barely below average for half of the county(eastern side). However, we can still get some good snowstorms in that period too. 

This image from Justin Berk, a meteorologist, shows that after Friday the 22nd, the temperatures start to plunge and become colder. But, it's not just one cold push. The cold is going to be sustained, from the last part of this month to the beginning of February. That is good for snow, because it gives a good period of time for some snow to fall.

In conclusion, we will start to see colder temperatures after this week, and the cold air will be sustained, while we are in a favorable pattern for snow, giving us a good chance for snowstorms. The likeliest time for significant snowstorms is between 01-24-2021 to 0-30-2021, as we get more data.

Small Pattern Update

 So you know that pattern I was talking about at the very, very beginning of the year? Well, there's been a slight change, and I am going to make a small update on it.

As this tweet from Mike Thomas shows, the NAO in the very upper part of the world is going to get very negative, and the blocking will relax. That will allow the storm track to go up north to us! As I and a lot of other people have said, after the 13-16th, a winter storm threat will become more serious and likely. When the block relaxes, and "breaks down", this is when we have seen some of our better snowstorms in our area. The next week will be warmer than usual, but when we get to the end of this month and the beginning of February, we might see some cooling and get some decent cold air. That's all for now.

Winter Forecasts 2020-2021

 These are the winter forecasts for this winter! This post got delayed by a long time, and I sincerely apologize for that. I have been working on this post since November, but never decided to finish it. Now it's 2021, and the first significant winter snowfall has fallen already (4 inches of snow w/o sleet, 4.25 inches with some ice). However, other than that there has been nothing. These maps can still somewhat hold up. I hope you enjoy! Sorry if it seems rushed, I tried to wrap everything as fast as I could.

WUSA 9:

Most of MoCo is in the 10-20" snow range, and the most northern is in the 20-30", and the very southern part is in the 2-10" snow range. They predict a below-average snowfall season this year. However, places more north and west will see snow totals close to average snowfall. The reason why they think this is because this year its a La Nina. This is not good for snow lovers because this is what a La Nina does(in their own words):

"The northern branch of the Jet Stream, the storm track, is forced north of the Mid-Atlantic taking the storms to our west, which draws up warm air from the south resulting in rain and not snow. Snowstorms must track south and east to hold in the cold air."

For Bethesda, they predict 13" of snow(avg = 19"), and for Dulles(closest to the amounts the northern part of the county gets), they predict 18" of snow, when the average is 23". So their range is 11-22 inches of snow for the whole county. That's below average. However, they are saying we WILL get more snow than last year. They also predict above-average temps as well. We will still get arctic outbreaks time to time though. They predict that the first measurable snow will be on Dec. 16. 

FOX 5 DC:

The Fox 5 map shows 12-24 inches of snow for the upper half of our county, while the lower half is in the 7-17 inches of snow range. This means that even if you are in the 7-17 inches of snow range, you could potentially see more snow than someone in the 12-24 inches of snow range(unlikely though), because you could see 17 inches while they could 15 inches, for example. Like the other forecasts, they predict a snowier winter compared to last year's, but still below average, and above average temperatures.

NBC 4:

NBC 4 predicts a below-average snowfall this year. They say that we will have above-average temps this year, and the main reason we aren't getting as much snow as we used to, is because of climate change and the warm winters. In Maryland, winter is the season that is warming the most, according to NBC 4. They also said that we will have a La Nina winter, which is not a good setup for snowfall. The southern part of MoCo(1/3 of MoCo) is in the 4-10" snowfall range. The other parts of MoCo are in the 7-15" snow range. For MoCo, according to this map, I would say its range is from 5-15 inches of snow.

"Over the last 20 winters, 13 have had below-average snow levels," says Doug Kammerer. "The truth is, we are just getting less and less snow around here due to climate change and warmer winters," says NBC 4. NBC 4 says for some actual snow, we need cold air, but its all locked up in the north.

ABC 7:

ABC7 is forecasting below-normal snowfall this year. About 2/5 of the county(southern part) are in the 3-13 inches of snow range, while the other 3/5 are in the 8-18" of snow range. For our county, I would say we will be seeing 6-14" of snow this year. They also predict a La Nina, which is not great if you want an average amount of snow.

If you look at the chart closely, you can see that after 2010, the annual snow in D.C has been reducing by a lot. There are spikes here and there, but for the most part, they have been starting to go down. The main reason for that would be of warming temps during winter. For temps this year, they predict it to be above average. They see an season cold snap which will make December the coolest month compared to the average temps during winter. This increases the chance of having a white Christmas in Maryland/MoCo/DC (8-20% through MD). They don't expect low temps to go in the single digits or lower, for DC at least. They expect 11-14 degrees to be the coldest of the season, if we even get there. Personally, I feel the northern side of MoCo might be able to touch the surface of single digits, if it even gets that cold. 

My Prediction:

So what do I think? I personally agree with all of these maps, and predict a below-average winter, in terms of snowfall. I also think that it won't be too much below average, so like 1-3 inches below the average snowfall, and there will be more snowfall than last year. Temperatures will be above-average, this has been a trend for the past 5 years. Don't expect the most wonderland-like winter, but also don't expect a barren winter, where it's mostly dry of snow. 2021 Update: With the new pattern that has gotten the weather community on the east coast hyped for some crazy winter weather, I actually predict an above average winter, in terms of snowfall. We haven't seen this type of pattern in quite a while. Read more about it here: https://mcpsweather.blogspot.com/2021/01/winter-forecasts-2020-2021.html. I think that we can see some good winter storms this year, but you never know. Also, I am thinking, from next year onward, to create my own winter forecast maps, so comment on what you think of it! Should I make them, or should I do something else? Let me know. Thank you always, for the incredible support you have given. It really helps me to make the best posts I can.

A new year, a new pattern, and a new storm potential!

Read the summary down below if you don't want to read the whole article; this weather news impacts people as far south as Florida and Texas. The first part is for DMV readers, though.

Happy new year to everyone! Hopefully, we can put back 2020 and move on. As the new year has come, we also have a chance of some snow, on Tuesday, and then something else to watch, during the time period of January 8th.

This tweet from the Capital Weather Gang says the chances for over an inch of snow (SPI) is 1/10, and the chances are rising. The Tuesday snowflakes part of the tweet is nothing too crazy to look forward to, but it is the last part of the tweet that is interesting, "next week as the pattern becomes friendlier for snow." 

This is the part that is for all readers, including the ones that aren't located in the DMV.

The pattern is important for winter weather, as it can decide how much moisture or cold air we get. Last year, we had the moisture but were just lacking the cold air. In the past 5 years, we haven't really gotten any storm that was crazy(With the exception of the 2015-2016 winter and maybe the 2018-2019 winter). This winter, for the entire U.S(as far as I am concerned), is a La Nina winter, which isn't good for snow in our area, because of the warm waters RIGHT next to the Atlantic. When the moisture comes(precip), there is warm air in place and there is rain. Right after, there is cold air, but no moisture. However, we can still see some above-average snowfall, even in a La Nina.

This map shows the pattern that will be coming in the next few days(Credit to Nikhil Trivedi for getting this picture, the picture was taken from his tweet.) If you don't understand this at all(like I do), the blueish colors represent the cold air. Due to anomalous ridging(which means that all of the warm air is in the Arctic air, or at least I think so), the cold air gets displaced and put to the south(Mid-Atlantic and interior southeast), which means we get cold air(certain about the pattern bringing cold air to us).  This means that places like Florida and Georgia could see some significant snow and winter weather! This is the same type of pattern that occurred during the epic and awesome winter of 2009-2010, where D.C alone almost measured 5 feet of snow and is the winter where we got the most snowfall recorded. (The interior Northeast didn't get much snow though that year). We got big, huge snowstorms and blizzards, that occurred next to each other(These storms were close to as big as the blizzard of 2016!). This could finally bring us the winter that we snow lovers in the Mid-Atlantic and Southeast have been waiting for for a long time. These kinds of storms and patterns could close schools, even through virtual learning! This is one of the most exciting things about winter weather I haven't seen in a LONG time. I know I am hyping this too much, but we have everything in place! Now... we just wait. The potential storm on January 8th is the first storm in this pattern. 

This picture, taken by Matthew Cappucci(a meteorologist for the Capital Weather Gang), explains this pattern much better. This shows that in the Northeast + Mid-Atlantic(most of it), there is increased winter potential for some good storms, and as the picture above also shows, cold air locked into most of Pennsylvania and down to include most of the southeastern and central USA. In the interior southeast(Georgia, Arkansas), there is also an increased severe weather potential for you guys(thunderstorms, tornadoes, etc.). And in the west coast, and the upper Midwest, the temperatures will be above average. There's also an active storm track coming, which is why we have a good bet on some good winter weather. Our area is above the storm track, which is good, since it means that we will be in the storm track. I will be watching that Jan 8-9 storm, and making posts about it soon.

Summary:

If you didn't read the entire article and just want a summary, there's a pattern in place for our area that will lock in cold air for the Mid Atlantic, the Southeast, and a good chunk of the central US. There will be increased winter potential for the Northeast and increased severe potential in the interior Southeast. The upper midwest and west coast will see above-average temperatures. The DMV could see some snowflakes on Tuesday, and there's a bigger storm on Friday-Saturday that will be the first storm of this new pattern. Right now, snow lovers around the east coast are rejoicing. Thank you for reading!