Mid to Long Range Discussion ~ 2023

[buckeyefan1]

16 minutes ago, Upstate Tiger said:

OK.  Added thread.  Maybe Buckeye or someone can pin it...

Pinned    Letssssssssssssssss gooooooooooooooooooooooooooooo!

[Upstate Tiger]

Not that I am hedging my bets or anything.... but still a signal for something to follow next weekend in case ya'll try and run me out of town this weekend.

 

[NorthHillsWx]

30 minutes ago, Upstate Tiger said:

Not that I am hedging my bets or anything.... but still a signal for something to follow next weekend in case ya'll try and run me out of town this weekend.

 

There’s been a signal for something in the 17-19th timeframe along with some actual cold air unlike with this weekend’s system 

[GaWx]

 The 12Z EPS has a gradually developing -AO starting ~Feb 22nd. The 12Z GEFS is similar. Monday's weeklies also had something similar along with a full fledged -AO/-NAO getting established by the first few days of March. That's what I'm going to be looking for starting around then in response to the upcoming SSW.

[Met1985]

7 minutes ago, GaWx said:

 The 12Z EPS has a gradually developing -AO starting ~Feb 22nd. The 12Z GEFS is similar. Monday's weeklies also had something similar along with a full fledged -AO/-NAO getting established by the first few days of March. That's what I'm going to be looking for starting around then in response to the upcoming SSW.

How do things look currently with the SSW?

[GaWx]

24 minutes ago, Met1985 said:

How do things look currently with the SSW?

 An increasingly high chance at a major peaking in at or just over a week. Now that the progged warming peak is only 7-8 days away and the start of the rapid warming is only 4 days out, the chances of it not happening are dropping rapidly as we're now within a pretty forecast-able timeframe.

[Met1985]

1 minute ago, GaWx said:

 An increasingly high chance at a major peaking in at or just over a week. Now that the progged warming peak is only 7-8 days away and the start of the rapid warming is only 4 days out, the chances of it not happening are dropping rapidly as we're now within a pretty forecast-able timeframe.

Good stuff. Keep us updated about it. It's been very interesting following your posts about this major SSW.

[NorthHillsWx]

Gfs keeps the 17th-19th window open at 18z. There is also a signal on the GEFS for this timeframe 

[Upstate Tiger]

Nice

 

[NorthHillsWx]

26 minutes ago, Upstate Tiger said:

Nice

 

EPS has a different look but GFS is definitely trying to press the cold at the end of the month. Hopefully it settles further east but at range it’s a very good look.

I still think we have a small shot of something during the 17-19th period followed by a warmup and then the final week of the month will need to be watched. 

[GaWx]

 It is now near a certainty that the SSW of next week will be a major. Supporting this are today's Euro weeklies, which show 100% of the 51 members now having the 60N 10 mb winds go below 0 m/s (westerly).

 The mean gets down to an impressive -12 m/s, down from the prior run's -10 m/s. Also, the new run's mean switches to westerly on 2/16 and stays that way for 3 weeks! The old run's mean was westerly only for one week.

 Consistent with this is the transition of the Arctic's H5. After the next 13 or so days of continued solid +AO/NAO and above normal H5 in the E US, which is not unusual near and somewhat after a SSW, a transition toward a -AO/NAO begins during the week of 2/20 although the E US stays mainly mild. This transition starts several days earlier than the prior run.

 On ~2/25, it goes to -AO and ~2/27 it goes to -NAO with both quicker than the old run. H5 hts rise along the west coast. The NE US cools to BN near the end of Feb and the SE NN. There's a full fledged -AO/-NAO for all of March, similar to the old run but starting a few days sooner. The E US is BN to NN the entire month, vs NN on the old run.

 In summary, the Euro weeklies are even more on board for a downward propagation of the major SSW into the troposphere getting started late month. That's what the greater than 40 mb Scandinavia-Greenland dipole of early this week had suggested.

 

[SnowDawg]

Three cheers for the death of La Niña!! 

 

[Met1985]

56 minutes ago, GaWx said:

 It is now near a certainty that the SSW of next week will be a major. Supporting this are today's Euro weeklies, which show 100% of the 51 members now having the 60N 10 mb winds go below 0 m/s (westerly).

 The mean gets down to an impressive -12 m/s, down from the prior run's -10 m/s. Also, the new run's mean switches to westerly on 2/16 and stays that way for 3 weeks! The old run's mean was westerly only for one week.

 Consistent with this is the transition of the Arctic's H5. After the next 13 or so days of continued solid +AO/NAO and above normal H5 in the E US, which is not unusual near and somewhat after a SSW, a transition toward a -AO/NAO begins during the week of 2/20 although the E US stays mainly mild. This transition starts several days earlier than the prior run.

 On ~2/25, it goes to -AO and ~2/27 it goes to -NAO with both quicker than the old run. H5 hts rise along the west coast. The NE US cools to BN near the end of Feb and the SE NN. There's a full fledged -AO/-NAO for all of March, similar to the old run but starting a few days sooner. The E US is BN to NN the entire month, vs NN on the old run.

 In summary, the Euro weeklies are even more on board for a downward propagation of the major SSW into the troposphere getting started late month. That's what the greater than 40 mb Scandinavia-Greenland dipole of early this week had suggested.

Great stuff! Thanks for the update.  Lot's of things are going on in the upper atmosphere.  Fascinating. 

[GaWx]

1 hour ago, Met1985 said:

Great stuff! Thanks for the update.  Lot's of things are going on in the upper atmosphere.  Fascinating. 

 Thanks and you're welcome. I forgot to add that the MJO will (as you probably already realize) on its own be favorable to get rid of the SE ridge/torch by late month and into March if model consensus is correct. That hopefully will help out the Pacific side.
 
 So, it appears that we may have a combo of a much improved Pacific thanks to the MJO and the end of La Niña in combo with -AO/-NAO from the SSW to make a cold March a very realistic possibility in the SE US. If that happens, it won't be out of the realm of possibilities for March to be the coldest one since at least 2013.

[NorthHillsWx]

Ouch, long range ensembles now mostly hold onto the SE ridge idea through the end of the month. Ugly doesn’t do it justice. Not sure if the fat lady has sung but she’s warming up, as we do too. 

[lilj4425]

12 minutes ago, NorthHillsWx said:

Ouch, long range ensembles now mostly hold onto the SE ridge idea through the end of the month. Ugly doesn’t do it justice. Not sure if the fat lady has sung but she’s warming up, as we do too. 

I think we’re all ready for Spring anyways. This Winter has sucked. If it isn’t going to snow give me 70 and sunny. 

[BooneWX]

1 hour ago, NorthHillsWx said:

Ouch, long range ensembles now mostly hold onto the SE ridge idea through the end of the month. Ugly doesn’t do it justice. Not sure if the fat lady has sung but she’s warming up, as we do too. 

At this point, I think I’m good with that. I had my evening jog in shorts and a t-shirt last night and it reminded me how taxing the early darkness and the endless rainy days have been. Give me 9 pm sunsets, mid 70s and towering thunderclouds.

[wncsnow]

4 minutes ago, BooneWX said:

At this point, I think I’m good with that. I had my evening jog in shorts and a t-shirt last night and it reminded me how taxing the early darkness and the endless rainy days have been. Give me 9 pm sunsets, mid 70s and towering thunderclouds.

Yep I'm pretty much done with this winter. This little diversion seems to be nothing more than a mirage in the endless sea of southeast death ridge

[eyewall]

18 hours ago, SnowDawg said:

Three cheers for the death of La Niña!! 

 

too little too late unfortunately but glad to see it go.

[SnowDawg]

2 minutes ago, eyewall said:

too little too late unfortunately but glad to see it go.

 I'm more or less just glad to see it go to perhaps be more optimistic going into next winter.

[GaWx]

 A midmonth major SSW is about to occur. It has been very well predicted by the GFS:
 

1. Something to keep in mind is that despite relatively high forecast skill in the strat out several weeks after a SSW (note dark colors in top of image below), the skill goes down quickly in the much more difficult to forecast troposphere (note the light colors on the bottom of the image below starting out only two weeks) in the aftermath of one and thus likely won't be clearly seen for quite some time:

2. A warm E US is actually pretty common during and for much of the two week period following a SSW. It is only after this period when any change to a cold pattern typically takes hold in the E US, if it is ever going to do so. So far, the jury is out, but long range signs remain promising for the start of a multi-week long significant -AO/-NAO (as per yesterday's Euro weeklies) around the last days of Feb and then dominating March. Also, the greater than 40 mb Scandinavian-Greenland dipole early this week is based on Simon Lee's studies usually an indicator that any SSW will propagate to the troposphere within a few weeks of it. Finally, MJO forecasts in combination with this remain favorable to end the SE ridge domination by early March.

[Met1985]

2 minutes ago, GaWx said:

 A midmonth major SSW is about to occur. It has been very well predicted by the GFS:
 

1. Something to keep in mind is that despite relatively high forecast skill in the strat out several weeks after a SSW, the skill goes down quickly in the  much more difficult to forecast troposphere (note the light colors on the bottom of the image below starting out only two weeks) in the aftermath of one and thus likely won't be clearly seen for quite some time:

2. A warm E US is actually pretty common during and for much of the two week period following a SSW. It is only after this period when any change to a cold pattern typically takes hold in the E US, if it is ever going to do so. So far, the jury is out, but long range signs remain promising for the start of a multi-week long significant -AO/-NAO (as per yesterday's Euro weeklies) around the last days of Feb and then dominating March. Also, the greater than 40 mb Scandinavian-Greenland dipole early this week is based on Simon Lee's studies usually an indicator that any SSW will propagate to the troposphere within a few weeks of it. Finally, MJO forecasts in combination with this remain favorable to end the SE ridge domination by early March.

Great stuff Larry! I love your updates on this. Keep them coming brother. Thank you.

[GaWx]

3 hours ago, Met1985 said:

Great stuff Larry! I love your updates on this. Keep them coming brother. Thank you.

You're welcome. Glad you like them!

 I'm now going to repost an image put together by Weather Desk with temperature maps from some past SSW cases that shows that it is often warm in the SE US for the 15 days starting with the SSW followed by sharply colder on days 16-30. Some good examples with that pattern shown below: 1/2/19, 2/12/18, 1/7/13, 3/24/10 (to an extent), 1/21/06, and 2/11/01 (to an extent). 

 So, of these 9 recent cases, 4 are strong examples and 2 others are modest examples. Of the recent La Niña examples shown here, 2/12/18 and 1/21/06 are 2 of the strong cases and show very well the warm SE 1-15/cold SE 16-30. Those two La Niña SSWs, like the current case, had 40 mb+ Scandinavian-Greenland dipoles prior to an SSW and later were downward propagating (they're the only 2 of these 9 cases like that). In the current case, days 1-15 would likely be either 2/15-3/1/23 or 2/16-3/2/23. So, days 16-30 would likely be either 3/2-16/23 or 3/3-17/23. I suppose they may even call the SSW date 2/17/23. These are just guidelines, of course, as the timing of effects of no two SSWs are exactly alike:

[Met1985]

16 minutes ago, GaWx said:

You're welcome. Glad you like them!

 I'm now going to repost an image put together by Weather Desk with temperature maps from some past SSW cases that shows that it is often warm in the SE US for the 15 days starting with the SSW followed by sharply colder on days 16-30. Some good examples with that pattern shown below: 1/2/19, 2/12/18, 1/7/13, 3/24/10 (to an extent), 1/21/06, and 2/11/01 (to an extent). 

 So, of these 9 recent cases, 4 are strong examples and 2 others are modest examples. Of the recent La Niña examples shown here, 2/12/18 and 1/21/06 are 2 of the strong cases and show very well the warm SE 1-15/cold SE 16-30. Those two La Niña SSWs, like the current case, had 40 mb+ Scandinavian-Greenland dipoles prior to an SSW and later were downward propagating (they're the only 2 of these 9 cases like that):

Fascinating Larry! And you can definitely see the big shift in the last two from very warm to absolutely frigid.  I really think that is where we are headed especially with the favorable mjo coming along towards the end of this month. Great stuff again! Im definitely looking forward to seeing how all this plays out.

[StantonParkHoya]

If anyone outside of the mountains sees snow this dreadful winter, I will eat my hat. It’s time for spring.

[Jmoon]

22 minutes ago, StantonParkHoya said:

If anyone outside of the mountains sees snow this dreadful winter, I will eat my hat. It’s time for spring.

I hear ya but when has it not been spring weather the entire so called winter this year.

[NorthHillsWx]

25 minutes ago, StantonParkHoya said:

If anyone outside of the mountains sees snow this dreadful winter, I will eat my hat. It’s time for spring.

Watch us get some crap white rain event in mid March that leads to 25 pages of posts and then some whitened mulch. That would send this winter out in the style it deserves 

[kvegas-wx]

28 minutes ago, StantonParkHoya said:

If anyone outside of the mountains sees snow this dreadful winter, I will eat my hat. It’s time for spring.

Pre-emergent is down.  Fertilizing end of Feb and I'll be mowing by mid March.  Bank it!! 

What an absolute dud of a winter.

[tarheelwx]

My blueberry bushes look like they’re ready to pop open.  They’ll probably open and then we’ll get a couple weeks of solid winter in March. 
TW

[Grayman]

7 minutes ago, tarheelwx said:

My blueberry bushes look like they’re ready to pop open.  They’ll probably open and then we’ll get a couple weeks of solid winter in March. 
TW

Please report to the sanitarium.