Another La Nina Incoming for the 2024-2025 Winter

[tron777]

Hate that we’re already in MJO watch mode . But we know we’re getting to the time of year its influence is significant . Your worry about the -PDO squashing its progression is a concern. Along with that progression, I think it needs to stay strong as well to really shake the 500mb pattern up

Agreed... The MJO is the only chance we've got at the moment. Cheering for the Euro especially.

[tpweather]

Great Posts folks. If the same pattern over the past couple of months continue then what you are seeing is no doubt a milder winter though offset by some decent cold attacks because the cold should build up quite nicely in much of Canada imo. I agree that you can take some items that happen during many of the La Nina's but not everything because there are many things besides the cooling of ocean water around the equator that end up telling us what may happen. I do believe the jet stream will be near us during the winter which I do believe will give us plenty of rainfall and hopefully some snowfall. How mild we get though and we know this from the past is snow cover and when you get little to no snow cover in the central plains this can really cause some warm days in mid-winter for that area and that will try and push northeast and another reason I believe the air masses will collide a few times this season. Problem of course is do we get some of these warmer air masses that bully their way into the Ohio Valley and if so how far north before they meet their demise. I agree with Bgoney about long term forecasts and almost anyone can bring up a model and this model will say this and another will say that but you must dig much deeper imo. Remember sometimes you can't see the forest for the trees.

[tron777]

My normal SST anomaly source from NOAA isn't updating so I will use Tropical Tidbits for this post. Anyway, if you look at the current SST anomalies below by clicking on this link:

https://www.tropicaltidbits.com/analysi ... obal_1.png

You will notice something that is sticking out like a sore thumb. Note the colder waters over the Bering Sea, Aleutians and into the Gulf of Alaska. Then, look south of there at the warmer waters off of Asia / Japan on towards the West Coast of North America. This SST configuration is a by product of the recent storminess that's been pounding Alaska and the -PDO. This should act to enhance storminess and the Pacific Jet over the next month. I expect November to start getting active with snow cover continuing to build in AK and Canada, For the CONUS, we should start to see more cold and snow over the Rockies and Western US with ridging in the Central states nudging into the East from time to time as well. Rainfall amounts for the OV TBD, but overall, I do expect on avg for us to remain on the mild side.

Now with that being said... as we've discussed recently, the MJO may also have its say with this whole thing. If the amplitude of the current wave can hang on and remain strong into Phase 7 by Nov and (God willing) make it into the colder phases 8, 1, etc etc.... then we could certainly see a colder and stormier pattern develop sometime in the second half of Nov into early December which would give winter a nice early start for us.

In the what can go wrong dept... the MJO wave could weaken as we have said thanks to the severely -PDO and the above SST configuration. We have seen this happen time and time again, haven't we? However, if it does hold on, what kind of change to the overall pattern, the La Nina, and -PDO could the strong MJO wave induce? The MJO in my opinion is a wild card right now. If some of the modeling is right, we will be in for some interesting changes. If incorrect and this thing weakens, then the call of mild weather with below normal snowfall even for December would be spot on. If the MJO remains strong and gets towards 7 and especially 8... we have got a shot at an early start to winter.

In conclusion, I am going to start talking about the MJO more and more as time goes on because we really need to start paying more attention to it. You can see the models yourself here:

https://www.cpc.ncep.noaa.gov/products/ ... r_wh.shtml

Yesterday's Teleconnections from the GEFS that can also be found on the CPC site, again if correct, COULD start reflecting this change with the MJO. Look at how the majorly positive AO starts to drop. NAO drops a little but overall positive and the PNA starts to rise even though it still is negative.

https://www.cpc.ncep.noaa.gov/products/ ... ions.shtml


You can also monitor the MJO in real time using the Aussie data which can be found here


http://www.bom.gov.au/climate/mjo/


Kyle Macritchie's experimental MJO model forecast can be found here:


https://www.kylemacritchie.com/meteorology/mjo.php


Again folks, I would still go mild and snowless at this time. I truly would and you know how it pains me to type that! But at the same time, let's continue to keep an eye on the MJO to see if maybe, just maybe, we could see something break our way positively for a change for us snow lovers.

[tpweather]

Great Post Les and really nothing to add. I need to start working on my snowfall prediction and probably will be early next week. Heading to Wisconsin on Thursday and will be back Monday. That will give me a few days to make the prediction. The upcoming winter season is another headache and again sometimes giving a 3 month prediction is almost impossible especially if you localized that prediction. Not sure how to give out that forecast and may just give out 2 weeks at a time and see if that works better.

[tron777]

Great Post Les and really nothing to add. I need to start working on my snowfall prediction and probably will be early next week. Heading to Wisconsin on Thursday and will be back Monday. That will give me a few days to make the prediction. The upcoming winter season is another headache and again sometimes giving a 3 month prediction is almost impossible especially if you localized that prediction. Not sure how to give out that forecast and may just give out 2 weeks at a time and see if that works better.

Hope you have a safe trip Tim (and a great time also)! The MJO, Tellies, etc are difficult to predict past 2 weeks as you know so that maybe a good way to go using a 2 week prediction instead of 3 or 4 months. For the snowfall contest, we can't do that so we submit our guesses there and hope for the best. You know how it works around here. One storm can make or break a season and that's just how it goes with our latitude.

[Bgoney]

CPC latest winter forecast attempt. About as good as it gets (temps) imo for a large section of central and Midwest parts of the country(for cold) , compared to recent winters, I know that’s not saying a lot. Honestly, I think NOAA has done better than any of the internet people and companies, as far as winter forecasting the last several years

IMG_2476.jpeg

[tron777]

Assuming the above maps are correct, with the way the temp forecast lines up, it should be active for us with above normal precip. You can of course get snow in a warm pattern, but luck becomes more of a factor unfortunately. To be honest I have seen much warmer looks from other models so we should probably take the CPC and run!

[Bgoney]

Assuming the above maps are correct, with the way the temp forecast lines up, it should be active for us with above normal precip. You can of course get snow in a warm pattern, but luck becomes more of a factor unfortunately. To be honest I have seen much warmer looks from other models so we should probably take the CPC and run!

No doubt, a near normal temp regime would seem like a very cold winter for many

[tron777]

The MJO (per the Aussies) is currently in phase 5, getting closer to 6. It'll still be another 7-10 days before we know for sure if it's going to make it into 7 or even get close to 8. The bigger news of the day is that the +AO is breaking records for October. As of yesterday, it was at +4.8 which is a record for October. The previous record was +3 point something so it has been smashed! This means that the PV is going to be gaining strength very quickly and the cold is going to stayed locked up tight for the foreseeable future.

[tron777]

It appears that they are getting rid of wind chill watches / warnings and advisories and it is being replaced by extreme cold watches and warnings. What the heck is this? The criteria has also changed. Check out the below graphic from the boys:

https://www.weather.gov/images/iln/2024 ... iteria.png

[Bgoney]

It appears that they are getting rid of wind chill watches / warnings and advisories and it is being replaced by extreme cold watches and warnings. What the heck is this? The criteria has also changed. Check out the below graphic from the boys:

https://www.weather.gov/images/iln/2024 ... iteria.png

Anything to get schools, and businesses and government to get more days off .

[tron777]

It appears that they are getting rid of wind chill watches / warnings and advisories and it is being replaced by extreme cold watches and warnings. What the heck is this? The criteria has also changed. Check out the below graphic from the boys:

https://www.weather.gov/images/iln/2024 ... iteria.png

Anything to get schools, and businesses and government to get more days off .

I also hate the fact that everything continues to get dumbed down for the general public. Drives me nuts!

[Bgoney]

No November thread yet so I’ll post this here . EU ensembles look to me like the first few days of possible rains and a Swesterly flow will be short lived as we go right back into a NWesterly mid level flow . That PAC pattern is in full beast mode and like we talked earlier the MJO is going to have perform majorly to really shake things up

[tron777]

No November thread yet so I’ll post this here . EU ensembles look to me like the first few days of possible rains and a Swesterly flow will be short lived as we go right back into a NWesterly mid level flow . That PAC pattern is in full beast mode and like we talked earlier the MJO is going to have perform majorly to really shake things up

Yep and it's certainly not slam dunk ether that the MJO will come through. I still think the tropics have a trick up their sleeve yet also. I will get the Nov thread started here in a bit.

[tron777]

The MJO is in Phase 6 now and per the modeling, it is expected to go thru Phase 7 later this month and into Nov, and eventually Phase 8 during the 1st week of the new month. Then models diverge. The Aussies and GFS want to keep it going and into Phase 1 by the 2nd week of Nov. The Euro wants to weaken the MJO and through it into the COD from Phase 8, so the wave dies and it never makes it into Phase 1. Due to the developing La Nina and especially the severe -PDO, it is going to be tough for the MJO to take a tour through those colder phases 8, 1, and 2. We have seen that play out time and time again over the past several winters. This is why I am focusing a lot of attention on the current MJO wave to see how far it can make it. We will need another week or two to see how this shakes out.

I'm not as concerned about the La Nina though. I still believe that the severely -PDO is driving the pattern again. That promotes a +EPO and keeps the cold to the north with a faster Pacific jet flooding Canada and the Lower 48 with mild Pacific air. The only hope we have is if we can get periods of a -WPO to force the North Pacific high to be more poleward with would in turn, get the EPO negative to allow for Canada to fill up with cold and hopefully get it into the Central and Eastern US versus only the Western US like what is happening now.

[Phr0z3n]

The PDO seems to be weakening a little bit this week.

IMG_0318.jpeg

I’m hoping beyond hope that continues. Throughout the years I’ve always liked our chances with a -EPO scenario more than with a -NAO. IMO our winters have done better especially downwind of the lakes with that scenario. We can even have a -PNA -EPO which is alluded to this winter when looking at cfs,canspis,and even euro weeklies are picking this up. With the MJO becoming stronger I’m wondering if the Nina will even reach weak status, but as Tron has indicated in other posts I also agree 100 percent we are at the mercy of the PDO.

[tron777]

The PDO seems to be weakening a little bit this week.
IMG_0318.jpeg
I’m hoping beyond hope that continues. Throughout the years I’ve always liked our chances with a -EPO scenario more than with a -NAO. IMO our winters have done better especially downwind of the lakes with that scenario. We can even have a -PNA -EPO which is alluded to this winter when looking at cfs,canspis,and even euro weeklies are picking this up. With the MJO becoming stronger I’m wondering if the Nina will even reach weak status, but as Tron has indicated in other posts I also agree 100 percent we are at the mercy of the PDO.

So nice to see you posting again, Phr0z3n! I think the Nina will be weak / cold neutral. But it's strength is really not of a concern to me. It's the -PDO. That thing has been driving the bus for our last several winters more so then any other atmospheric indicator (IMO). If it can weaken then we may indeed have some very good wintry periods. But if it doesn't, the mild call will end up unfortunately being right. To me, it all boils down to it. It is a big reason why the MJO waves keep dying and never take a tour through the cold phases. We keep seeing phases 4-6 and that is due to the -PDO (some thanks to the Nina and IOD too I suppose) I also wonder about the high solar activity. It's off the charts high! That can't be good either although my knowledge in this area is lacking.

[tpweather]

Great Posts above this one and no doubt the PDO is the main driver. Can that change and to some point yes but we need more storms to end up off the east coast of Asia and love to see them in November and December. This pdo has been so strong that the northern hemisphere this October has been warmer than normal for most places and finally we are starting to see that change but no doubt a later than normal time for the cold to start and build up. Sure a few cold shots here and there and yes early frost for us but overall a milder Oct for many. Les I have no reason to point to the solar activity because my knowledge on that subject is so low and something I don't use with forecasts because of that reason.

[tron777]

Great Posts above this one and no doubt the PDO is the main driver. Can that change and to some point yes but we need more storms to end up off the east coast of Asia and love to see them in November and December. This pdo has been so strong that the northern hemisphere this October has been warmer than normal for most places and finally we are starting to see that change but no doubt a later than normal time for the cold to start and build up. Sure a few cold shots here and there and yes early frost for us but overall a milder Oct for many. Les I have no reason to point to the solar activity because my knowledge on that subject is so low and something I don't use with forecasts because of that reason.

I try to use solar somewhat Tim but my knowledge is also lacking. The +QBO continues to strengthen too, but the main concern I have is no doubt the -PDO. Let's keep an eye on that as November rolls on.

[Phr0z3n]

I’m thinking this La Niña is never going to make it. There is another MJO wave to monitor

IMG_1022.gif

Looks a lot stronger also than the one we just encountered. This makes sense as the IOD just went negative.

IMG_1024.png

You can also see in the upper ocean heat content anomalies that this current MJO wave is propagating around 140E.

IMG_1023.gif

Propagation means La Niña will weaken. The latest plot shows us entering phase 7

IMG_1025.gif

And it’s almost a match for todays euro run

IMG_1026.png

So I guess what I’m trying to say is a lot of people blindly forecasted this winter on La Niña like conditions, but what happens when those conditions never develop? I’m not sure how this will affect if at all our winter, but at least we can monitor MJO waves for favorable phases in these next few months.thoughts anyone?

[tron777]

Wonderful post Phr0z3n! My only thoughts to counteract a favorable MJO phase is the extremely -PDO and the -IOD. Despite the La Nina either staying cold neutral / weak... wouldn't those two factors still allow the majority of the MJO forcing to be in Phases 4-6 which we know are the kiss of death in winter? If the -PDO would weaken that would really allow for something else to drive the pattern and then yes... the MJO could get into those favorable phases of 8, 1, and 2. Like you said in a previous post, we are at the mercy of the -PDO. That has been my reasoning all along for going mild with below normal snowfall. I was never once concerned about the La Nina getting out of hand. The last several winters IMO the ENSO state hasn't mattered. The PDO being so strongly negative has dominated the Pacific pattern.

[Phr0z3n]

Wonderful post Phr0z3n! My only thoughts to counteract a favorable MJO phase is the extremely -PDO and the -IOD. Despite the La Nina either staying cold neutral / weak... wouldn't those two factors still allow the majority of the MJO forcing to be in Phases 4-6 which we know are the kiss of death in winter? If the -PDO would weaken that would really allow for something else to drive the pattern and then yes... the MJO could get into those favorable phases of 8, 1, and 2. Like you said in a previous post, we are at the mercy of the -PDO. That has been my reasoning all along for going mild with below normal snowfall. I was never once concerned about the La Nina getting out of hand. The last several winters IMO the ENSO state hasn't mattered. The PDO being so strongly negative has dominated the Pacific pattern.

I might just be grasping here but I think that’s a really good sign the warmer waters made it to 140E. To me that means the anomalous La Niña 850 winds are flipping and allowing the warmer waters move to more favorable phases. My other thought is the strength of the emerging MJO wave could be enough to jumble up things with how global circulation works. Maybe the MJO wave could churn up enough sea water to disrupt any warming that might be transported poleward through Hadley and Pharrell cells outside of the Nino regions that might be fueling some warming in the PDO regions. I’m not sure how much it will help but I’m hoping that it might.

[tron777]

Wonderful post Phr0z3n! My only thoughts to counteract a favorable MJO phase is the extremely -PDO and the -IOD. Despite the La Nina either staying cold neutral / weak... wouldn't those two factors still allow the majority of the MJO forcing to be in Phases 4-6 which we know are the kiss of death in winter? If the -PDO would weaken that would really allow for something else to drive the pattern and then yes... the MJO could get into those favorable phases of 8, 1, and 2. Like you said in a previous post, we are at the mercy of the -PDO. That has been my reasoning all along for going mild with below normal snowfall. I was never once concerned about the La Nina getting out of hand. The last several winters IMO the ENSO state hasn't mattered. The PDO being so strongly negative has dominated the Pacific pattern.

I might just be grasping here but I think that’s a really good sign the warmer waters made it to 140E. To me that means the anomalous La Niña 850 winds are flipping and allowing the warmer waters move to more favorable phases. My other thought is the strength of the emerging MJO wave could be enough to jumble up things with how global circulation works. Maybe the MJO wave could churn up enough sea water to disrupt any warming that might be transported poleward through Hadley and Pharrell cells outside of the Nino regions that might be fueling some warming in the PDO regions. I’m not sure how much it will help but I’m hoping that it might.

You could easily be on to something here for sure. We've been so jaded by the PDO at the same time, that it is hard for me to let that idea go. All trends must come to an end though since nothing lasts forever in weather. I am interested to see what the October reading will be. The Sept reading from NOAA was a ridiculous -3.54 which is record breaking. There is a website that gives you a daily PDO reading too (has a chart) but I can't find that site right now.

[Phr0z3n]

Current 7 day ssta anomaly map shows cooling in the pdo region. Let’s hope this continues

IMG_1046.png

I also noticed the polar vortex is nice and strong at 10mb

IMG_1047.png

I’m also liking how operational and ensembles are picking up on a potential cold shot/first lake effect snows the week of the 18th. Just random thoughts on a Saturday…

[tron777]

Good morning Phr0z3n! I agree with the cold shot coming around the 20th but I think it maybe short lived. IMO the MJO wave is weakening from 7 / 8 and it will head into the neutral circle. Then later this month and into December, the MJO might make another run at Phases 4-6, If so that'll be warm thru mid December. Hopefully we would then line up for a colder surge again for Christmas. The timing would be nice if it worked out like that. I'm still pretty concerned about the -PDO since it actually got stronger in the October reading -3.84. I'm not sure how sustainable any blocking would be with such a hostile Pacific. There are signs of an incoming -NAO which gets us back to more seasonable air but there are also indications that it may hook up for a time with the SE Ridge. We'll see I guess.