December 2021 Weather Discussion

[tron777]

Everyone needs to save this awesome site in their bag of tricks.

https://www.meteonetwork.it/models/mjo/

It shows you MJO phases based on the ENSO state. So for this winter, we're using the MJO phases for a La Nina. It's in French but easy to figure out. In the first block you have the ENSO state: Nino, Nada (neutral) and Nina. Then across the top in French you have the months of the year. So for MJO phase 7, look at the DIC box (DIC is December) then click on Nina 7. MJO Phase 7 in a La Nina for December. You'll get the following look:


nina_7_dic_ok.png


That shows a gradient pattern so good for overrunning events if you're on the correct side of the baroclinic zone. The biggest take away is a massive -EPO which should stick out like a sore thumb on this composite image. That should get some cold into the Lower 48. How far south is a question because you still have the SE ridge to deal with as well. It's definitely an active pattern for sure.

Great site! Thanks for sharing. Oddly enough, here's phase 6 in December for a Nina.

No +PNA at all right now so IMO what that tells us is the MJO is not driving the pattern. The amplitude is too weak. If we can get a stronger wave in the West Pac, the GFS / GEFS should start showing a cooler look as what we're seeing on the foreign models.

[tpweather]

Everyone needs to save this awesome site in their bag of tricks.

https://www.meteonetwork.it/models/mjo/

It shows you MJO phases based on the ENSO state. So for this winter, we're using the MJO phases for a La Nina. It's in French but easy to figure out. In the first block you have the ENSO state: Nino, Nada (neutral) and Nina. Then across the top in French you have the months of the year. So for MJO phase 7, look at the DIC box (DIC is December) then click on Nina 7. MJO Phase 7 in a La Nina for December. You'll get the following look:


nina_7_dic_ok.png


That shows a gradient pattern so good for overrunning events if you're on the correct side of the baroclinic zone. The biggest take away is a massive -EPO which should stick out like a sore thumb on this composite image. That should get some cold into the Lower 48. How far south is a question because you still have the SE ridge to deal with as well. It's definitely an active pattern for sure.

Great site! Thanks for sharing. Oddly enough, here's phase 6 in December for a Nina.

No +PNA at all right now so IMO what that tells us is the MJO is not driving the pattern. The amplitude is too weak. If we can get a stronger wave in the West Pac, the GFS / GEFS should start showing a cooler look as what we're seeing on the foreign models.

Les if the Aussie's are correct that wave has started and is much stronger than anything in the past few months.

[tron777]

No +PNA at all right now so IMO what that tells us is the MJO is not driving the pattern. The amplitude is too weak. If we can get a stronger wave in the West Pac, the GFS / GEFS should start showing a cooler look as what we're seeing on the foreign models.

Les if the Aussie's are correct that wave has started and is much stronger than anything in the past few months.

I sure hope so Tim! Having to wait 2-3 weeks for a pattern change (if you believe the GFS) sucks! Hopefully the foreign models have the right idea. A - We won't be waiting as long B - A possible wintry chance next week and C - What they are showing is not a torch at all like the GFS has.

[Bgoney]

Everyone needs to save this awesome site in their bag of tricks.

https://www.meteonetwork.it/models/mjo/

It shows you MJO phases based on the ENSO state. So for this winter, we're using the MJO phases for a La Nina. It's in French but easy to figure out. In the first block you have the ENSO state: Nino, Nada (neutral) and Nina. Then across the top in French you have the months of the year. So for MJO phase 7, look at the DIC box (DIC is December) then click on Nina 7. MJO Phase 7 in a La Nina for December. You'll get the following look:


nina_7_dic_ok.png


That shows a gradient pattern so good for overrunning events if you're on the correct side of the baroclinic zone. The biggest take away is a massive -EPO which should stick out like a sore thumb on this composite image. That should get some cold into the Lower 48. How far south is a question because you still have the SE ridge to deal with as well. It's definitely an active pattern for sure.

Boy, I wish it were that simple. There are so many variables I'd like to plug into that. The very first one , is how does a raging -PDO factor in?

[tron777]

Everyone needs to save this awesome site in their bag of tricks.

https://www.meteonetwork.it/models/mjo/

It shows you MJO phases based on the ENSO state. So for this winter, we're using the MJO phases for a La Nina. It's in French but easy to figure out. In the first block you have the ENSO state: Nino, Nada (neutral) and Nina. Then across the top in French you have the months of the year. So for MJO phase 7, look at the DIC box (DIC is December) then click on Nina 7. MJO Phase 7 in a La Nina for December. You'll get the following look:


nina_7_dic_ok.png


That shows a gradient pattern so good for overrunning events if you're on the correct side of the baroclinic zone. The biggest take away is a massive -EPO which should stick out like a sore thumb on this composite image. That should get some cold into the Lower 48. How far south is a question because you still have the SE ridge to deal with as well. It's definitely an active pattern for sure.

Boy, I wish it were that simple. There are so many variables I'd like to plug into that. The very first one , is how does a raging -PDO factor in?

I agree. The composite is showing if the MJO is driving the pattern in a La Nina in December with the MJO Phase being Phase 7. That is typically the look you'd see. It's not factoring in other things like the -PDO, -QBO etc etc. Nothing is weather is that easy as we all know, and it never will be. Just another tool that's all. We can never take anything as gospel. The -PDO is definitely a contributing factor as well as the GOA Low. There is no doubt about it. Those two working together have been driving the pattern. No doubt about. We have to hope for something else to take over as the pattern driver. Otherwise we won't have a winter this year if the same thing keeps repeating the next 3 months. Luckily in weather, other things can and do take over as the pattern driver. If the MJO can somehow do its thing, than the GOA Low will be shoved eastward into Canada. If it doesn't happen then we'll see more days like today. 65 degrees imby right now and that just isn't right in December.

[Microburst]

Looks like our next chance of precip comes on Sunday, per the 12z EURO.

[tron777]

Hey Daniel! Nice to see you posting. Sun late afternoon and Sun night is a rain maker for sure. Models vary on amounts but a half inch is possible. Then around the Tues night and Wed period that is when some snow is possible unless the GFS is right then it's a cutter and all rain.

[tpweather]

The one theme starting Sunday is a much more active pattern. Will this be rain/mix or snow and I believe we are looking at a mess next week with 3 systems between Sunday and the following Saturday. There is cold air to grab hold of but how much can we grab. Sort of strange with the Euro and GFS because the GFS is holding energy further back to the west while the Euro is keeping things moving right along. I am with the Euro on this as this is how I thought next week would go with several systems but again not a slam dunk by any means. I believe Joe made a great point the other day about the barometric zone and how it looks to set up near us. If this happens then tons of moisture available and the gom should be wide open much of the week. Just happy to see some action to follow.

[MVWxObserver]

Great to see you, Daniel!

Currently 50 here in Greenville and progged for the low 30s Fri morning.

[Bgoney]

Busy day, November dryness makes for perfect planting conditions, so if you want to plant shrubs perfect ti.e to do it before the wet weather next week. On To the models , kind of a battle going on , marginal cold EU vs slightly warmer GFS next week . Really not a pattern change as the warm, cold ,warm etc continues. But like we've said same pattern into December could bring slightly better chances for wintry precip. Still, I think the GFS will be closer to reality. Mentioned a few days ago for the tues/we'd period A few flurries possible along with a miserable mix for a time . Still a ways out so things can change.. Then where does the front stalls after that will determine who gets more heavy rain . OV/Tenn Valley/SE states are possibilitys.

[tron777]

18Z GFS tonight took a step towards the flatter unphased solution for next week. Looks pretty wet Sun night upcoming as well.

[Bgoney]

Just another day in Siberian paradise....



A low of -55.7C (-68.3F) was observed in Delyankir on December 1.


In addition, Delyankir’s high for the day reached only -48.2C (-54.8F) — a new record low-max.

Schools in the region have been cancelled –as is the law whenever temps drop below -50C– , “one of the earliest occurrences of frost below -55C in the region in history!”


Elsewhere, Oymyakon reported a minimum temperature of -54.4C (-65.7F) in the early hours of Wednesday morning; Yurty hit -54.3C (-65.7F); and the infamous Verkhoyansk registered -50.1C (-58.2F).

[tpweather]

Just another day in Siberian paradise....



A low of -55.7C (-68.3F) was observed in Delyankir on December 1.


In addition, Delyankir’s high for the day reached only -48.2C (-54.8F) — a new record low-max.

Schools in the region have been cancelled –as is the law whenever temps drop below -50C– , “one of the earliest occurrences of frost below -55C in the region in history!”


Elsewhere, Oymyakon reported a minimum temperature of -54.4C (-65.7F) in the early hours of Wednesday morning; Yurty hit -54.3C (-65.7F); and the infamous Verkhoyansk registered -50.1C (-58.2F).

Good Morning Bgoney, several days ago the extended forecast had temps in the -70 range so looks pretty accurate to me. This is another example of Mother Nature balancing the earth as regions in the Antarctica have been well above normal and its late spring for them. Except for Northeast Asia and Alaska it was a late start to colder temps but again Mother Nature is making up for lost time.

Looking at all the fog advisories from south central Texas to western Florida along the gulf states. This tells me that moisture is gathering and all we need is something to ignite that area and we see that coming starting later Sunday. Going to be a wet 7 days starting Sunday an will we be able to pull enough cold air south to have some of the precip in the form of snow. The NWS in many areas are hedging their bets and going with the forecast of a chance of rain and snow and at this point I understand where they are coming from.

The QBO fell again and has been going trending that way since last November except a minor rise in March. I believe that has hit rock bottom and with the set up in November my guess is that number was lower early in the month and is rising. If that number would continue to fall in December that is something we will need to pay attention too.

[tron777]

Good morning all! Here is the QBO index reading info. This is at 30 MB. We went from -16.56 for Oct down to -19.14 for Nov. Still in a moderately -QBO phase. It's not driving the pattern yet obviously. La Nina is clearing driving the bus along with the -PDO which is common in Nina's. So the cold stays locked up north or out west and we deal with mild weather and the SE ridge here. That looks to be the case going forward unfortunately.

Look for a good soaking Sun late afternoon and esp Sun night. 1/2 to 1" of rain is expected. Could even see some t-storms with the frontal passage early Mon morning. Mon will feature rain ending early with windy conditions and falling temps. Cold Tues in the 30s. Then for Tues night into Wed the next one moves in with the kitchen sink possible. Another system moves in by late next week / next weekend too. Snow chances are there but the warm air is lurking so it's going to be tough to get an all snow system. You hear that term thread the needle often, that rings true for next week.

[cloudy72]

Could even see some t-storms with the frontal passage early Mon morning.

Overnight Euro agrees with your thinking, Les! And me as well!

[tpweather]

Usually when I see an elevated threat for thunder in December that usually means some heavy rain. Sure we could hear a clap of thunder but this is usually a stronger sign of some heavy rainfall. Believe we will continue to see amounts go up on the models for the period late Sunday and Monday. There will be a cutoff of the heavy rain and probably near the river is my guess at this point.

[tron777]

Could even see some t-storms with the frontal passage early Mon morning.

Overnight Euro agrees with your thinking, Les! And me as well!

GFS looked like it was showing it also. Probably why the QPF totals have gone up to like 1 to 1.5". I'm going with 0.50-1" since not everyone will get those heavier totals. But some will get amounts higher then what I am forecasting for sure.

[tron777]

Usually when I see an elevated threat for thunder in December that usually means some heavy rain. Sure we could hear a clap of thunder but this is usually a stronger sign of some heavy rainfall. Believe we will continue to see amounts go up on the models for the period late Sunday and Monday. There will be a cutoff of the heavy rain and probably near the river is my guess at this point.

I agree Tim... Cincy on south looks to be the best area for elevated instability at this point.

[tron777]

SnowTalk! https://www.wave3.com/2021/12/03/snowta ... pdate-123/

[cloudy72]

I know we talked about the winds later Sunday into early Monday. Here is what the 12z 3km NAM says - looks like potential advisory criteria north of the river.

[tpweather]

SnowTalk! https://www.wave3.com/2021/12/03/snowta ... pdate-123/

I hope most folks tune into Brian's videos. He does such a great job but he explains on this episode why folks in the weather world are having troubles with the upcoming pattern and how folks are in different camps and why that is happening. I believe on here many of us are looking at things in somewhat a different way and those outcomes are big when it comes to the forecast each one of us throws out. He talks about how tough the upcoming pattern is and why he is leaning one way but not full scale in and that is how I have been touting this pattern for at least a week.These are fun when trying to forecast and you must read between the lines no matter what data you look at and it is very time consuming. Sometimes when the weather gets active I will spend 8-10 hours just looking over everything and then checking it again and again. We all want to throw out the most accurate forecast possible and there are going to times when the baseball looks like a beach ball and you can't miss and other times it looks like a ping pong ball and almost impossible to hit. Everyone on here has different strengths and that is what makes it such a great forum. The good thing is we all care and love the weather and why I spend much of my time studying especially during times of more interesting weather.

[tron777]

I know we talked about the winds later Sunday into early Monday. Here is what the 12z 3km NAM says - looks like potential advisory criteria north of the river.

Exactly why I am doing the last leaf grinding of the season today and tomorrow.

[tron777]

SnowTalk! https://www.wave3.com/2021/12/03/snowta ... pdate-123/

I hope most folks tune into Brian's videos. He does such a great job but he explains on this episode why folks in the weather world are having troubles with the upcoming pattern and how folks are in different camps and why that is happening. I believe on here many of us are looking at things in somewhat a different way and those outcomes are big when it comes to the forecast each one of us throws out. He talks about how tough the upcoming pattern is and why he is leaning one way but not full scale in and that is how I have been touting this pattern for at least a week.These are fun when trying to forecast and you must read between the lines no matter what data you look at and it is very time consuming. Sometimes when the weather gets active I will spend 8-10 hours just looking over everything and then checking it again and again. We all want to throw out the most accurate forecast possible and there are going to times when the baseball looks like a beach ball and you can't miss and other times it looks like a ping pong ball and almost impossible to hit. Everyone on here has different strengths and that is what makes it such a great forum. The good thing is we all care and love the weather and why I spend much of my time studying especially during times of more interesting weather.

Awesome post Tim! As Brian said (and we all agree here) that there are conflicting signals. Does the warm win out because of La Nina and the -PDO or can the MJO wave be strong enough to get us into Phase 7 for a better chance at wintry weather? We shall see as usual.

[tron777]

Nothing much to report change wise from the 12Z OP GFS and GEFS. The OP GFS is still showing cutter city with most systems and the GEFS still has a shot at wintry weather next week. CMC and UKMET too.

[tpweather]

Les the two major things I have been looking at with the first being the strong system heading into western Alaska. Many times these are true pattern changers and especially with all the cold that has stored up in Alaska and getting a system to move that cold eastward is key. Second is the lower 48 is finally getting stormy and yes more of a mid-late November type of pattern however we are able to tap some of the cold air in Canada. The past two weeks the cold has continued to build in northern and central Canada. With the uptick in weather systems and I still believe a parade of storms instead of one big storm we are able to tap some of the cold but with the systems moving quickly makes it hard to warm up before the next system rolls in. Already seeing the weather service in southern parts of central Canada lower their temps for early next week by at least 10 degree since a few days ago and this tells me the cold is on the move.