bluewave

No problem. Not saying I know for sure what is going to happen. Just not a big fan of this persistent -PDO La Niña background state .I don’t mind it as much when it’s uncoupled like Jan 22 and Dec 20 to Jan 21. But it’s very tricky to try and figure out ahead of time when it’s going to couple or not. Plus we have these interference patterns which can arise when the ENSO and PDO our out of phase. Also these troughs seem to find a way to sneak in out West during recent years.

The relevant part is how even a weak -PDO with an El Nino can put a trough in the West like 72-73.

The issue with WWBs coming on so late is that any oceanic kelvin wave generated would also be too late to move the El Niño much more past what we have already seen. Most fall oceanic kelvin waves that have sharp El Niño warming get generated by WWBs during late summer into September. This year we had stronger trades and an absence of WWBs. So any potential kelvin wave warming would come after the El Niño has already peaked.

Tug of war between El Niño in the tropics and -PDO in subtropics or extratropical regions.

It doesn’t have to if the -PDO is coupled well. We can remember back in the 18-19 El Niño that struggled to couple how the well coupled -0.42 -PDO was enough to place the trough in the West. But each winter is different so we’ll just have to see how things play out. Plenty of variables and combinations to factor in.

MJO 7 region forcing west of the Dateline like we are currently getting can mimic a MJO 5 when the PDO is very negative.

Hopefully, the MJO 4-6 doesn’t rebound as much as we saw with the last record +IOD back in 19-20. That event only suppressed convection near the Maritime Continent into early December. So IODs are mainly a fall event and the influence wanes by the winter. Once the IOD dropped under +1 in December 2019, the Maritime continent convection returned.

OCT…….6-8…..0.49

The only real winters in the 90s were 93-94 and 95-96.

Crazy how Sandy was exactly a year later.

Those were the glory days for the Euro when it believe it was the first model to show an unusually early season snowstorm in the Northeast. Even though it was too snowy at the immediate coast, it was still the greatest early season snowstorm on record.

This would actually be a good trend if we got it in the winter. Much stronger blocking to the north preventing the primary from cutting to the Lakes. So we get a forced redevelopment to our south. If this was the winter, we would be hoping later runs don’t correct north. New run Old run

With the current upper ocean heat value just under +1, we continue to see Nino 3.4 pulling back from the highs in late September. The current daily value of +1.44 is well below the Euro monthly average forecast of 2.03 for October. So this could be one of the greatest Euro forecast misses issued in September for October. https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table ECMWF 2.03

Yeah, the NPAC firehose jet is knocking down the +PNA ridge too quickly so primary runs to the lakes. The STJ can’t completely take over like we would want to see. There has been quite a bit of this type of storm track behavior in recent years.

The cold coming up doesn’t look too impressive for October. But it will certainly feel that way due to the 80s to start the month. So it’s all relative.

The Euro is already running too warm for October. It has a monthly average of 2.03. As of 10-07 Nino 3.4 is +1.52. So the dailies would have to increase to at least above +2.25 in the coming weeks for that monthly average number to verify. But there are no big WWBs in the forecast plus the OHC is currently to low to support such a steep rise. https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-sst_table ECMWF 2.03

October is turning out to be a blend of El Niño and La Niña 500 mb composites. So this is what we get with a borderline strong El Niño around +1.5 and a -PDO near record low levels. The ridge NW of Hawaii and strong low south of Alaska in October is classic La Niña. But the ridge over NW Canada is more El Niño. A La Niña pattern in October has a +EPO and an El Niño -EPO. So we can see the back and forth with the EPO in the forecast. https://ds.data.jma.go.jp/tcc/tcc/products/clisys/enso_statistics/index.html October El Niño 500 mb composite October La Niña 500 mb composite Forecast has elements of both composites

Sure. This article has the charts and a link to the paper. https://news.climate.columbia.edu/2019/06/24/pacific-ocean-cold-tongue/

While the oceans have been steadily warming as a whole, it has been uneven. So some areas such as the IO into WPAC and NW Atlantic with slowing AMO have been warming more rapidly. Plus we have the mystery of the EPAC cold tongue defying the global trends like the famous cold pool south of Greenland. But even though the slowing AMOC has been implicated in that cold pool, the EPAC cold tongue remains a mystery. Below is an excerpt from a recently published article in New Scientistmagazine: “For years, climate models have predicted that as greenhouse gas emissions rise, ocean waters will warm. For the most part, they have been correct. Yet in a patch of the Pacific Ocean, the opposite is happening. Stretching west from the coast of Ecuador for thousands of kilometres lies a tentacle of water that has been cooling for the past 30 years. Why is this swathe of the eastern Pacific defying our predictions? Welcome to the mystery of the cold tongue. This isn’t just an academic puzzle. Pedro DiNezio at the University of Colorado Boulder calls it ‘the most important unanswered question in climate science’. The trouble is that not knowing why this cooling is happening means we also don’t know when it will stop, or whether it will suddenly flip over into warming. This has global implications.” “SOEST scientists are on the forefront of researching this critical question in climate science and related topics–for example, tropical Pacific climate change in general, El Niño, and Pacific decadal variability,” said Malte Stuecker, assistant professor in the SOESTDepartment of Oceanography and International Pacific Research Center, who was also featured for the New Scientist article. “For how long the cooling in the eastern Pacific persists and when exactly it will flip to warming will have big implications for regional climate predictions and adaptation efforts – including for Hawaiʻi.” To make progress on the cold tongue mystery, Stuecker co-leads an international coordinated working group under the World Climate Research Programme called TROPICS.

Mostly climatology in that region. You can also look at all of the seasonal SST forecast models which show a rebound during the winter there. This year we don’t have as strong an Indian Ocean forcing signal as 2019 so not getting the same signal for the super strong SPV like that winter. But there are many things which can affect the SPV so there is always a bit of wait and see.

I expanded the box a bit more since the forcing is sensitive to a larger area than the one you posted. The current cooling is a result of the IOD like we saw at the same time in 2019. But once this IOD fades, the SSTs will naturally rebound like we saw by the winter of 2020. These stronger +IODs are a relatively short lived events only lasting several months.

The odd thing about this event is that the timing of El Niño global temperature spikes are usually in the late winter or spring. We never had a global temperature spike of this magnitude from the summer into the fall while an El Niño event was developing. The 15-16 peak came in late February as we would expect from the El Niño lag and usual timing of the monthly peak. Plus this event is only around +1.5C rather than the super levels in 15-16 of a record +2.6. The one theory as to timing that I heard was that Nino 1+2 got an unusually early start late last winter. And that global temperatures are very sensitive to the EPAC region.

It’s normal for the WPAC SSTs to decline a bit during El Niño periods. But this September was the warmest for an El Niño in September from the Dateline back to Asia. We can remember the record SST rebound following the 2019 fall IOD event.

Don, it will be interesting to see if the record is a result of a slight undermeasurement at the park taken too late allowing time to melt or settle. Notice the other surrounding airport sites with more frequent measurements made it to an inch on 2-27-23. Data for February 27, 2023 through February 27, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Snowfall NJ CEDAR GROVE TWP 0.4 W CoCoRaHS 2.8 NY RIDGE 1.8 SE CoCoRaHS 2.4 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 2.0 NY ISLIP-LI MACARTHUR AP WBAN 1.8 NJ NEWARK LIBERTY INTL AP WBAN 1.2 NY LAGUARDIA AIRPORT WBAN 1.1 NY JFK INTERNATIONAL AIRPORT WBAN 1.0 NY NY CITY CENTRAL PARK WBAN 0.9

You are talking about two different different things. Global warming is something that has been observed and seasonal forecasts involve projections about the future. You will notice in most good studies about global warming they mention that they are not sure how things will change in the future in regard to regional climate trends. Regional climate modeling is a new frontier that is still pretty young. The global climate models are a more generalized and have been doing a good job with broader global temperature trends even though this current temperature spike is outside the upper limit. It’s highly reasonable to expect when we change a climate state so rapidly there will be model differences as to the finer details. So nobody is shutting down any debates.