El Nino 2023-2024

[Daniel Boone]

1 hour ago, stadiumwave said:

CFS Weeklies, AO & NAO forecasts.

 

   So far, any attempt of Models showing a trend to positive for both indexes have quickly reverted back to negative. Hopefully the CFS is right here. If so, we may not have a mild December. Cansips is obviously placing some emphasis on a -PDO , and of course alot on the Nino as Grit alluded to. It doesn't appear to give much credence to blocking in December and tbh, imo, not as much as it should as the Blocking it's showing for Jan/Feb. 

     Just my has been antique old school thought's fwiw. 

[so_whats_happening]

3 hours ago, Terpeast said:

Alright, I did it. Here's my outlook.

 

I wonder if there is a connection of +AMO and -PDO phase and vice versa, also when they are in tandem +/+ or -/-. I never really took the chance to see if this was something or not and since they are multi decadal oscillations im curious if there is something to it like when we have an extremely +AMO do we tend to have more -PDO?

[WestMichigan]

9 hours ago, stadiumwave said:

One thing to keep in mind with these seasonal forecasts. A lot can change in a month for sure.

Here's the October updates forecast for NOV:

 

Here's the NOV update for NOV:

 

Just a wee bit different.

October map was using 1981-2010 while the November map is using 1991-2020.  What would these look like if done using the same climatological norms?  There are definitely differences, I am not arguing that, but it would sure be nice to see them with the same reference point.

[GaWx]

1 hour ago, WestMichigan said:

October map was using 1981-2010 while the November map is using 1991-2020.  What would these look like if done using the same climatological norms?  There are definitely differences, I am not arguing that, but it would sure be nice to see them with the same reference point.

@stadiumwaveaccidentally posted the Oct map as the top map instead of old Nov. Regardless, the CANSIPS old Nov map (regardless of 1981-2010 vs 1991-2020, which was a good catch) was also mainly AN and thus will likely turn out significantly too warm for Nov in the E US once all is said and done due to the cold first half. So, the idea behind the post that the CANSIPS run of last month for Nov will almost certainly end up significantly too warm at least in the E US is a good one.

 Also, the CANSIPS Oct forecast was too warm in the SE.

 Based on the persistent EPS forecasts for a weak SPV in Dec, which favors a -AO, I think there’s a pretty good chance that the current (and old) CANSIPS forecasts for a near normal Dec will also end up too warm, but we’ll see.

[40/70 Benchmark]

46 minutes ago, GaWx said:

@stadiumwaveaccidentally posted the Oct map as the top map instead of old Nov. Regardless, the CANSIPS old Nov map (regardless of 1981-2010 vs 1991-2020, which was a good catch) was also mainly AN and thus will almost definitely turn out significantly too warm for Nov in the E US once all is said and done due to the cold first half. So, the idea behind the post that the CANSIPS run of last month for Nov will almost certainly end up significantly too warm at least in the E US is a good one.

 Also, the CANSIPS Oct forecast was too warm in the SE.

 Based on the persistent EPS forecasts for a weak SPV in Dec, which favors a -AO, I think there’s a pretty good chance that the current (and old) CANSIPS forecasts for a near normal Dec will also end up too warm, but we’ll see.

We need to make sure that PV disruption continues on schedule in early December, though....any later, and the impact of it will be delayed until after the new year...which is my default premise, anyway.

[GaWx]

8 minutes ago, 40/70 Benchmark said:

We need to make sure that PV disruption continues on schedule in early December, though....any later, and the impact of it will be delayed until after the new year...which is my default premise, anyway.

Agreed. And I think that may be even more the case if there ends up being an actual SSW, especially major, because they sometimes occur when it is mild in the E US. As it appears you’re implying, major SSWs that end up getting well down into the troposphere often lead to cold that takes 10-14+ days following one to start having a big impact. So, if there is a major SSW in mid Dec that propagates way down, any intense cold resulting from this may not even get started til after Jan 1.

[40/70 Benchmark]

Just now, GaWx said:

Agreed. And I think that may be even more the case if there ends up being an actual SSW, especially major, because they sometimes occur when it is mild in the E US. As it appears you’re implying, major SSWs that end up getting well down into the troposphere often lead to cold that takes 10-14+ days following one to start having a big impact.

I expect it to be major.

[40/70 Benchmark]

Dec ends up being a case of kick the can, I think....which will trigger a slew of tweet quotes from @snowman19and melt downs from the usual suspects.

[bluewave]

11 hours ago, stadiumwave said:

One thing to keep in mind with these seasonal forecasts. A lot can change in a month for sure.

Here's the October updates forecast for NOV:

 

Here's the NOV update for NOV:

 

Just a wee bit different.

One of the issues with some of these monthly seasonal forecasts is that they just repeat the initial conditions at the start of the month for the whole month. The CANSIPS and the CFS do this often. But sometimes the Euro monthly issued on the 5th does well with the whole first month. But it has been rare for any of these seasonal models to get the 2nd month or beyond correct in recent years.

[40/70 Benchmark]

@brooklynwx99Draftkings is opening up a line for the over/under on Roundy quotes attributing the delay of the December cold to that one last WWB.

[40/70 Benchmark]

We should make weenie emojis count as a post.

[GaWx]

13 minutes ago, bluewave said:

One of the issues with some of these monthly seasonal forecasts is that they just repeat the initial conditions at the start of the month for the whole month. The CANSIPS and the CFS do this often. But sometimes the Euro monthly issued on the 5th does well with the whole first month. But it has been rare for any of these seasonal models to get the 2nd month or beyond correct in recent years.

 That’s why I take modeled seasonal forecasts with a grain of salt. However, the Euro Weeklies have (based on many years of data) been forecasting the stratosphere through week 6 much more accurately than the troposphere as I posted about earlier. Thus, I tend to pay extra attention to strat forecasts of the extended Euro Weeklies. The persistent forecast for a weak SPV on the Euro in Dec is quite notable as a whopping 85% of the members have a weaker than normal SPV in mid Dec.

[Itryatgolf70]

1 hour ago, GaWx said:

 That’s why I take modeled seasonal forecasts with a grain of salt. However, the Euro Weeklies have (based on many years of data) been forecasting the stratosphere through week 6 much more accurately than the troposphere as I posted about earlier. Thus, I tend to pay extra attention to strat forecasts of the extended Euro Weeklies. The persistent forecast for a weak SPV on the Euro in Dec is quite notable as a whopping 85% of the members have a weaker than normal SPV in mid Dec.

It kinda blows my mind that the models can even predict that far out with any reasonable accuracy because patterns are constantly in flux, meaning changing quite often, especially with changing wavelengths. 

[40/70 Benchmark]

Hey, @griteater,

Have an update graphic through Sept/Oct?

[brooklynwx99]

1 hour ago, GaWx said:

 That’s why I take modeled seasonal forecasts with a grain of salt. However, the Euro Weeklies have (based on many years of data) been forecasting the stratosphere through week 6 much more accurately than the troposphere as I posted about earlier. Thus, I tend to pay extra attention to strat forecasts of the extended Euro Weeklies. The persistent forecast for a weak SPV on the Euro in Dec is quite notable as a whopping 85% of the members have a weaker than normal SPV in mid Dec.

there has been a noticeable trend towards a pretty big weakening of the SPV heading into December now

[DarkSharkWX]

does anyone have the updated daily pdo graph? these ones

[mitchnick]

6 minutes ago, DarkSharkWX said:

does anyone have the updated daily pdo graph? these ones

Link is here with graph on the right side of the page.

https://s2s.worldclimateservice.com/climatepanel/

[brooklynwx99]

-VP setting up near the dateline on the ECMWF weeklies as well. this is into the first week of December

very similar to the Modoki years and far west of the canonical EP super Nino years

[bluewave]

2 hours ago, GaWx said:

 That’s why I take modeled seasonal forecasts with a grain of salt. However, the Euro Weeklies have (based on many years of data) been forecasting the stratosphere through week 6 much more accurately than the troposphere as I posted about earlier. Thus, I tend to pay extra attention to strat forecasts of the extended Euro Weeklies. The persistent forecast for a weak SPV on the Euro in Dec is quite notable as a whopping 85% of the members have a weaker than normal SPV in mid Dec.

I saw that also. What the Euro is forecasting would be rare. Only 5 out of 44 SSWs on record occurred before January 1st.

 

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

 

 

[JVscotch]

18 minutes ago, brooklynwx99 said:

-VP setting up near the dateline on the ECMWF weeklies as well. this is into the first week of December

very similar to the Modoki years and far west of the canonical EP super Nino years

Interesting.  Though the U.S has a lot more lift like the stronger years.   Generally with your thoughts though for the further west forcing will help us win more times this winter compared to normal or the warmer/stronger years, especially as we head into mid-winter.  

[Terpeast]

11 minutes ago, bluewave said:

I saw that also. What the Euro is forecasting would be rare. Only 5 out of 44 SSWs on record occurred before January 1st.

 

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

 

 

I’m no expert on SSW events so I’d defer to @GaWx on this, but if this plays out as forecasted, this could be an interesting January for most of us up and down the EC. 

[40/70 Benchmark]

15 minutes ago, bluewave said:

I saw that also. What the Euro is forecasting would be rare. Only 5 out of 44 SSWs on record occurred before January 1st.

 

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

 

 

Gracias.

[40/70 Benchmark]

You guys are clutch with the incessant graphics feed into an ongoing outlook effort lol

[Terpeast]

1 hour ago, 40/70 Benchmark said:

You guys are clutch with the incessant graphics feed into an ongoing outlook effort lol

Can't wait to see yours!

[snowman19]

Hey, [mention=2064]griteater[/mention],
Have an update graphic through Sept/Oct?

Unfortunately the Modoki index is going to be on life support. The WPAC has begun cooling significantly and the warmth in 1+2 moved as far west as it’s going to, it moved into the middle of region 3.4 and has stopped there. Also, found this interesting:

[snowman19]

[griteater]

3 hours ago, 40/70 Benchmark said:

Hey, @griteater,

Have an update graphic through Sept/Oct?

October numbers won't be out until a few more days, but here was the update that includes Aug/Sep.  Based on Oct SST images, I don't think it will change much for the Sep/Oct value

[griteater]

14 minutes ago, snowman19 said:

 

For some reason, everything is shifted a bit farther west than you'd expect with this year's El Nino / IOD (the color palette is reversed on the right side for the OLR comparison)

[snowman19]

October numbers won't be out until a few more days, but here was the update that includes Aug/Sep.  Based on Oct SST images, I don't think it will change much for the Sep/Oct value

Agreed.

[griteater]

4 hours ago, Terpeast said:

I’m no expert on SSW events so I’d defer to @GaWx on this, but if this plays out as forecasted, this could be an interesting January for most of us up and down the EC. 

The El Nino / -QBO combo is a good one for SSWs, -AOs, and -NAOs.  Posted this in the Winter thread a few months back...

 

And during El Ninos, Sudden Stratospheric Warmings (SSW) have occurred in 8/10 cases (80%) when the QBO was negative in winter (40mb on Jan 1).  And in the 8 cases where an SSW occurred during Nino and -QBO, the combined AO/NAO index was negative 6/8 cases (75%).

 

In contrast, when the QBO was positive in winter during El Ninos, SSWs have occurred in only 6/13 cases (46%).  And in the 6 cases where an SSW occurred during El Nino and +QBO, the combined AO/NAO index was negative in only 2/6 cases (33%).