snowman19

That is correct. I re-read up on it and the whole point of Judah’s SAI index is to measure the rate of snowcover buildup in Siberia, in October, especially mid-late October @kazimirkai As far as the northeast Pacific warm blob, I read that Paul is expecting it to continue cooling and not last into winter. Over the last few weeks it has been weakening and cooling, whether that continues or not remains to be seen

I thought October was the important month not September

Offsetting the WPAC warm pool may be a very tall task. The above normal anomalies out that way are still off the charts

It would not shock me to see an uncoupled (disconnected) SPV this winter where the SPV is weak but there’s a +AO at the surface, as Commoditywx showed in that tweet above. That looks like a very strong tendency of previous years with the -IOD and the Copernicus is showing it for November and December

Since 19-20, he always finds a way to predict a -AO/-NAO winter with a very weak SPV and major blocking every single year. He’s only gotten one right by default….20-21. And I get accused of being biased lol

The Copernicus model suite is showing the same total disconnect between the SPV and the TPV that we saw last winter. It’s showing them staying uncoupled in November and December with a very weak SPV, but a +AO/+NAM at the surface. Interestingly, the last times such scenarios happened was when we had a negative IOD @Stormchaserchuck1

The drought continues to worsen. Yesterday’s rain event underperformed what was expected earlier on in the week, not that it would have made much of a dent anyway. Soil moisture is also ridiculously below normal

As far as the WPO goes….I have to agree with you there. The WPAC SST pattern over the last couple of months up to now is matching past years that had predominantly +WPO winters. If that doesn’t change in a big way between now and the end of November, a +WPO winter would not surprise me

I agree with the BOM. A weak La Niña the remainder of the fall into at least early winter is inevitable

My opinion has not changed. I don’t care what the models say. I still believe we finish this season below 100 ACE. If I’m wrong so be it

My bias is not part of this conversation. I know you’re ready to start one of your 5th grade personal attacks

The same can be said every year. If this board were around for the 95-96 and 97-98 winters, I’m sure you would have had people saying 95-96 was going to be a warm and snowless winter because of the Niña and on the flip side, I’m sure you would have had the weenies trying to force a cold and snowy winter for the 97-98 super El Niño. There are biases at play every year

@Gawx Starting to wonder if we are seeing a secondary peak in this solar cycle

Very good call. It also looks dry as a bone which obviously is not good at all given the ongoing drought since the end of July

In theory, a -QBO should destabilize the tropical tropopause and cause a stronger, more robust MJO and on equator forcing/convection. Maybe this erratic behavior with the westward propagations and weak, low amplitude MJO waves is only temporary and will change as we go deeper into fall? Strong -IOD/La Niña playing a role? I’m honestly not sure besides saying to take a wait and see approach

The MJO waves have also been low amplitude unlike last year at this time when we were seeing strong waves and are projected to stay that way

The unusual westward MJO propagation continues

And on the PAC side, this -PDO cycle has been much stronger than the last one (1940’s-1970’s). I’ve seen a few articles blaming the record low arctic sea ice on this -PDO cycle

I think the question becomes when does the -IOD bottom out? Did it bottom out already or do we see another burst of strengthening in October. Either way the BOM and all models are projecting the -IOD event to continue the next few months. From the BOM: “The Indian Ocean Dipole (IOD) index has now met the negative IOD threshold (less than or equal to −0.4 °C) for 8 consecutive weeks, sufficient to be classified as a negative IOD event. The latest IOD index value for the week ending 14 September 2025 is −1.17 °C. The Bureau's model predicts the negative IOD event to continue throughout spring, with a return to neutral in early summer. This is consistent with most international models assessed and the typical IOD life cycle.” https://www.bom.gov.au/climate/enso/?ninoIndex=nino3.4&index=rnino34&period=weekly#tabs=Indian-Ocean

I don’t think we are going to see a big October burst in Atlantic tropical activity. This is how many months in a row now that people have been saying a big burst is coming? The finish line just keeps getting moved further and further forward in time. Now it’s October. This is becoming The Boy Who Cried Wolf. Eventually you have to acquiescence and admit defeat

@Stormchaserchuck1 IMO we are on the verge of finally going into a -AMO cycle

@Gawx

Also, a very strong -IOD signature here