El Nino 2023-2024

[40/70 Benchmark]

16 hours ago, 40/70 Benchmark said:

Not true.

https://www.researchgate.net/publication/349616356_Defining_El_Nino_indices_in_a_warming_climate

"In a warming climate. changes in tropical rainfall and even the intensity of tropical cyclones are more sensitive to changes in relative SST than to background warming (Johnson and Xie 2010, Ramsay and Sobel 2011). That is, the pattern of mean SST warming is important because the largest increase in rainfall will occur in the regions that warm the most relative to the tropical mean, referred to as the warmer-get-wetter paradigm (Xie at al 2010). Uniform surface warming in the tropics will thus not act to appreciably change the local stability and hence precipitation telconnections associated with ENSO".

I'm sure you will quote your on research and we can continue to have this literary sword fight, or simply wait to see who is right...we should know in about a month.

 

 

 

1 hour ago, bluewave said:

Through the rich get richer mechanism. The WPAC warm pool is one of the regions that sees an increase in tropical convection with warming SSTs. The paper you mentioned discussed subsidence regions in other areas of tropical oceans with warming. The previous papers I posted about the WPAC show increased convection there with rising SSTs and stronger MJO phases. 
 

https://www.pnas.org/doi/full/10.1073/pnas.0601798103#:~:text=The “anomalous gross moist stability,because of enhanced moisture convergence.

The “anomalous gross moist stability” or “rich-get-richer” mechanism (12) hypothesizes that the upped-ante differential moisture increase will yield increased precipitation within the convection zones because of enhanced moisture convergence. This mechanism also contributes to drying outside the strong convection zones and likewise should yield an approximately fixed spatial pattern whose amplitude grows in time with the tropospheric warming.

Among these are drying regions in Central America, the Caribbean, equatorial South America, and along the Atlantic intertropical convergence zone. Precipitation increases tend to occur inside the convection zones, including increases in the Southeast Asian summer monsoon. Increased precipitation also occurs in the equatorial Pacific, associated with changes in the dynamics of the equatorial cold tongue and local sea-surface temperature increase (15–18).

The pieces are saying the same thing. I haven't read your article, but the one that I presented, which involves RONI, simply specifies that this "rich get richer" and "warm get warmer" dynamic applies specifically to ENSO attributed warming RELATIVE to the mean background warming. You seem to be arguing more that its the background warming that is the driver. I hypothesize that that may be true when ENSO is not prominent, as was the case over the summer and into the early portion of the fall. This is why the forcing was displaced so far west when SST anomalies were biased well to the east during and shortly after the event's inception. Notice that said convective forcing has navigated slightly to the east since el Nino has taken over more...I know @snowman19 has pointed that out.

[GaWx]

 The latest EPS extended (bc) MJO forecast is quite encouraging if you want the best chance for BN cold to dominate the E US, especially mid-Atlantic south, late month into Jan from an MJO perspective because it shows weak MJO:

 Keeping this EPS weak MJO forecast in mind, look at the amplitude of the MJO when there were E US cold events during DJF: almost entirely weak

 

[mitchnick]

6 minutes ago, 40/70 Benchmark said:

Yea, funny that after all of that bickering we essentially agreed. Just a neurotic display of out passion that why focus and argue over the most subtle of details.

Some/Most won't believe contrary views unless someone of like thinking says/agrees with it. Happens in more than just weather, which goes without saying. 

[40/70 Benchmark]

45 minutes ago, GaWx said:

 The latest EPS extended (bc) MJO forecast is quite encouraging if you want the best chance for BN cold to dominate the E US, especially mid-Atlantic south, late month into Jan from an MJO perspective because it shows weak MJO:

 Keeping this EPS weak MJO forecast in mind, look at the amplitude of the MJO when there were E US cold events during DJF: almost entirely weak

 

I am with you on the cold being mainly mid Atlantic and south....I think any true arctic air holds off until February, once the SSW manifests. January will probably be near normal to slightly above in the NE...just cold enough to snow.

[GaWx]

 The latest AAM forecast (CFS ens) is dominated for the next month by a pretty robust +GLAAM, which is typically associated with El Niño:

[bluewave]

25 minutes ago, 40/70 Benchmark said:

 

The pieces are saying the same thing. I haven't read your article, but the one that I presented, which involves RONI, simply specifies that this "rich get richer" and "warm get warmer" dynamic applies specifically to ENSO attributed warming RELATIVE to the mean background warming. You seem to be arguing more that its the background warming that is the driver. I hypothesize that that may be true when ENSO is not prominent, as was the case over the summer and into the early portion of the fall. This is why the forcing was displaced so far west when SST anomalies were biased well to the east during and shortly after the event's inception. Notice that said convective forcing has navigated slightly to the east since el Nino has taken over more...I know @snowman19 has pointed that out.

The warming in this case includes the near record SSTs in the western El Niño regions in addition to the warmer Maritime Continent MJO 4-7 phases. My reference to RONI was in the way GaWx was hypothetically using it in his question. Not that RONI wasn’t a thing. But that perhaps the lower RONI values for this event reflected the much warmer SSTs than normal SSTs near the MJO 4-7 regions during such a strong El Niño event. My guess is that the RONI or MEI would be higher if the WPAC was as cool as it was 30 years again and the Nino regions didn’t have competition from the forcing extending further west. 

[40/70 Benchmark]

8 minutes ago, bluewave said:

The warming in this case includes the near record SSTs in the western El Niño regions in addition to the warmer Maritime Continent MJO 4-7 phases. My reference to RONI was in the way GaWx was hypothetically using it in his question. Not that RONI wasn’t a thing. But that perhaps the lower RONI values for this event reflected the much warmer SSTs than normal SSTs near the MJO 4-7 regions during such a strong El Niño event. My guess is that the RONI or MEI would be higher if the WPAC was as cool as it was 30 years again and the Nino regions didn’t have competition from the forcing extending further west. 

Oh, okay. I agree with you. The warmer west PAC absolutely plays into RONI and the MEI.

[bluewave]

Just now, 40/70 Benchmark said:

Oh, okay. I agree with you. The warmer west PAC absolutely plays into RONI and the MEI.

Yeah, it’s just that combining such a strong El Niño with MJO 4-7 phases results in a much warmer December pattern than usual for much of North America that we are seeing this month. 

[Terpeast]

35 minutes ago, GaWx said:

 The latest EPS extended (bc) MJO forecast is quite encouraging if you want the best chance for BN cold to dominate the E US, especially mid-Atlantic south, late month into Jan from an MJO perspective because it shows weak MJO:

 Keeping this EPS weak MJO forecast in mind, look at the amplitude of the MJO when there were E US cold events during DJF: almost entirely weak

 

Phase 7 by 15th (give or take). Still no can-kick

[Terpeast]

6 minutes ago, bluewave said:

Yeah, it’s just that combining such a strong El Niño with MJO 4-7 phases results in a much warmer December pattern than usual for much of North America that we are seeing this month. 

Better now than Jan/Feb

[40/70 Benchmark]

43 minutes ago, 40/70 Benchmark said:

I am with you on the cold being mainly mid Atlantic and south....I think any true arctic air holds off until February, once the SSW manifests. January will probably be near normal to slightly above in the NE...just cold enough to snow.

This is why I think January-February may play out like a somewhat milder version of 2003, where as the coast of SNE struggled in January and then cleaned up when joining the party in February.

[40/70 Benchmark]

12 minutes ago, bluewave said:

Yeah, it’s just that combining such a strong El Niño with MJO 4-7 phases results in a much warmer December pattern than usual for much of North America that we are seeing this month. 

Right...which is why December 2015 was so much warmer....same page.

I also expect a similar system to the January blizzard, though hopefully about 100mi further north

[Terpeast]

5 minutes ago, 40/70 Benchmark said:

 

I also expect a similar system to the January blizzard, though hopefully about 100mi further north

I think that’s the only part we’re NOT on the same page about 

[Volcanic Winter]

2 hours ago, 40/70 Benchmark said:

Right...which is why December 2015 was so much warmer....same page.

I also expect a similar system to the January blizzard, though hopefully about 100mi further north

Or, perhaps we can get the storm itself to widen by about 100 mi instead to keep all of us in the jackpot. That’s totally feasible, yes? 

May need to look at Day After Tomorrow for appropriate storm analogues … 

Seriously though, it’s fun when we can all cash in at some point, even with different events (though my area often shares big storms with yours, they’re normally the coast crawler MECS and HECS like 1/29/22 and thus are rarer). I get that winters can favor one area over another from time to time, (and more often than not that’s at your latitude or thereabouts). 

Here’s to hoping when all is said and done this winter has at least produced something notable for the majority of us. Until then, I defer to the excellent analysis you guys continue to fill this thread with. Disagreement is part of scientific debate and serves to broaden perspectives, so I’m here for that, too. 

[stadiumwave]

2 hours ago, Terpeast said:

Phase 7 by 15th (give or take). Still no can-kick

 

The deeper into Dec we get Phase 7 is not a bad phase per Roundy's MJO guidance 

 

[Terpeast]

9 minutes ago, stadiumwave said:

 

The deeper into Dec we get Phase 7 is not a bad phase per Roundy's MJO guidance 

 

That’s what I’ve been saying for a while. Some of our biggest snowstorms started as a wave in the north pacific while the mjo was in 7

[GaWx]

 This GEFS PNA forecast tells me that Dec is likely to end up with a +PNA. Should that be the case, that would mean that every month Jun-Dec will have had a +PNA. Since 1950, the only other year with a PNA>0 for all of those months was 2009:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

[40/70 Benchmark]

52 minutes ago, Volcanic Winter said:

Or, perhaps we can get the storm itself to widen by about 100 mi instead to keep all of us in the jackpot. That’s totally feasible, yes? 

May need to look at Day After Tomorrow for appropriate storm analogues … 

Seriously though, it’s fun when we can all cash in at some point, even with different events (though my area often shares big storms with yours, they’re normally the coast crawler MECS and HECS like 1/29/22 and thus are rarer). I get that winters can favor one area over another from time to time, (and more often than not that’s at your latitude or thereabouts). 

Here’s to hoping when all is said and done this winter has at least produced something notable for the majority of us. Until then, I defer to the excellent analysis you guys continue to fill this thread with. Disagreement is part of scientific debate and serves to broaden perspectives, so I’m here for that, too. 

All it would take if for the PV love to be a bit father north, or non existent.

[stadiumwave]

EPS, DEC 23

Paul Roundy's "Low pass MJO, ER Constructed Analog", DEC 27th...looks similar:

[GaWx]

Today’s Euro Weeklies SPV runs are similar to yesterday in that they don’t have any new can kicking though they maintain the Dec can kicking of the prior week of runs with only a moderately weak SPV then. A week ago the Dec SPV was significantly weaker. We need to see whether the can kicking looks like it will spread into Jan.

 But in Jan, today’s maintains a very weak SPV with a similar ~45-50% of members having a major SSW 1/3-22. I count ~16% (vs ~18% yest) that are sub -15, which would be a new record low for early to mid Jan. (The ~10% sub -20 and 2% sub -25 are same as yesterday.) It looks like the first clump is during 1/5-9 (from warming that really gets going in Siberia ~12/28) with a 2nd more spread out grouping 1/12-20. So, once the non-extended models reach the last few days of Dec, it will be quite telling about this first clump. Thus, we’ll start to know much more about the likelihood of that early clump being a real deal mid next week and learn more late next week.

  

Jan 11th EPS mean: still very weak

12/8 run: 15 m/s

12/7 run: 14 m/s

12/6 run: 12 m/s

12/5 run: 17 m/s

12/4 run: 14 m/s

12/3 run: 15 m/s

12/2 run: 15 m/s

12/1 run: 18 m/s

11/30 run: 23 m/s

11/29 run: 23 m/s

 

Check out this 10 mb temp anom and geopotential ht map for 1/8-15. Note the quite displaced mean SPV well S of the N pole at 70N and the high over S AK:

[GaWx]

Today’s ext GEFS has this at 10 mb as of Jan 2, which looks like the kind of Siberian map you often see preceding a major SSW: the warmest of that is -18C, which is well above normal. That warmth then rotates N around the SPV toward the Arctic over the subsequent few days. The EPS has a good number of members with a major SSW in early Jan that appear to be associated with this same warming. So, these two ensembles are suggesting to look toward early Jan for the first good opportunity for a major SSW. This GEFS run also has a cold E US/+PNA and developing high latitude blocking the first week of Jan. By then, the MJO appears to be headed toward weak 1-2-3, which would be cold supportive. So, regardless of how mild parts of mid to late Dec end up in portions of the E US, Jan would appear to be a whole other ballgame:

 

[stadiumwave]

I've read more whining on social media than I can bare. I've seen nothing change for the worse. The thought has always been a typical warmer El Nino DEC that toward the end of the month begins improving & into JAN has good winter potential. 

My analog package which consisted of 2 super El Ninos, 3 strong El Ninos, & 2 moderate had the typical Dec warmth. 

A nice JAN with colder conditions in SE & with a strong Aleutian low.

Aleutian low weakens & retrograde in FEB & that month has the strongest high latitude blocking. 

 

Winter ends late FEB & transitions to a warmer March. 

 

Headed onto January the 0z long-range GFS looks great. 

[snowman19]

This upcoming WWB and MJO constructive interference is going to have a boat load of subsurface/OHC warmth to work with. We may see very dramatic warming in both regions 3 and 3.4 at the end of this month

[Terpeast]

7 hours ago, stadiumwave said:

I've read more whining on social media than I can bare. I've seen nothing change for the worse. The thought has always been a typical warmer El Nino DEC that toward the end of the month begins improving & into JAN has good winter potential. 

My analog package which consisted of 2 super El Ninos, 3 strong El Ninos, & 2 moderate had the typical Dec warmth. 

A nice JAN with colder conditions in SE & with a strong Aleutian low.

Aleutian low weakens & retrograde in FEB & that month has the strongest high latitude blocking. 

 

Winter ends late FEB & transitions to a warmer March. 

 

Headed onto January the 0z long-range GFS looks great. 

Recent mjo got can kicked a few days to a week, though. But December was always going to be warm anyway. Still expecting Jan-Feb to be colder (near normal give or take a couple degrees)

[stadiumwave]

3 minutes ago, Terpeast said:

Recent mjo got can kicked a few days to a week, though. But December was always going to be warm anyway. Still expecting Jan-Feb to be colder (near normal give or take a couple degrees)

 

It did but inititial model guidance had it moving way to fast which smart money was always on a slower propagation. Models finally corrected. 

Everyone needs to keep in mind that models are not stellar at MJO forecast. And during active MJO winters models usually suck pretty bad. If they get MJO wrong then the overall 500mb pattern is more than likely wrong as well. As a rule of thumb I'd be skeptical of model guidance outside of 5 days on specific systems & 7-10 days on overall global patterns. 

[stadiumwave]

This may not look like much to some but the stratosphere forecast between Euro & GFS is a big difference:

 

[WxUSAF]

^said this in the MA forum, but if the euro is right and the vortex is displaced toward the eastern CONUS, there may be more cold-side risk than people are appreciating despite the mega winter ending grinch torch PAC jet. 

[ORH_wxman]

1 minute ago, WxUSAF said:

^said this in the MA forum, but if the euro is right and the vortex is displaced toward the eastern CONUS, there may be more cold-side risk than people are appreciating despite the mega winter ending grinch torch PAC jet. 

I actually mentioned something semi-similar in the New England forum about how the excessive EPO block (really a bit north of the classic EPO region…more into the Arctic Ocean) and the subsequent downstream PV near Hudson/Baffin has some correction potential to the south. This could be seen even in the week prior to Xmas. I know the post above was talking stratosphere, but those features are somewhat reflected in the upper troposphere. 
 

[mitchnick]

1 hour ago, stadiumwave said:

 

It did but inititial model guidance had it moving way to fast which smart money was always on a slower propagation. Models finally corrected. 

Everyone needs to keep in mind that models are not stellar at MJO forecast. And during active MJO winters models usually suck pretty bad. If they get MJO wrong then the overall 500mb pattern is more than likely wrong as well. As a rule of thumb I'd be skeptical of model guidance outside of 5 days on specific systems & 7-10 days on overall global patterns. 

This Eps product is pretty decent. You can read the full explanation at the link, but the colored dots represent each member of the Eps at 1 day for red, 5 days for pink, etc. Gives a much better idea of whether the mean is because of a consensus or an average of a huge spread with little confidence in the forecast.

https://charts.ecmwf.int/products/mofc_multi_mjo_family_index?base_time=202312080000

[GaWx]

OHC looked to have topped at least for now: