bluewave

That’s a good point. While we usually see divergence in the 11-15 day forecasts, the GEPS and GEFS are going -PNA. This is in contrast to the +PNA EPS. So it appears that the GEFS and GEPS are going with the -PDO and record warm pool east of Japan. While the EPS is trying to put its eggs more the El Niño basket. It will be interesting to see how this tug of war between competing influences plays out.

The CFS won the September forecast at 1.66 and the Euro and AUS were too warm at 1.89 and 1.98. 3.4 has been stuck between 1.6 and 1.7 all month as the WWBs were a no show this month.

This could be the first time we didn’t get the usual pressure rise along the equator over Indonesia. So the eqsoi isn’t showing the same response. This is why we didn’t get the usual El Niño strong WWBs. The models didn’t do a good job with this since several like the Euro and Australian had Nino 3.4 averaging close +2.0 for September.

Hard to believe that the last major hurricane landfall in the Carolinas was way back in 1996. All tropical storms or lower end hurricanes. But flooding has been their biggest issue with multiple record breaking events such as Florence. https://www.aoml.noaa.gov/hrd/hurdat/All_U.S._Hurricanes.html

Just give me one to two solid months this winter with a raging STJ and some blocking. This new paper is another conformation of the semi-permanent La Niña background state due to the warming WPAC. It is similar to the recent papers showing the stronger and more persistent MJO 4-6 phases. So I am hoping for a decent El Niño pattern before we flip again back to La Niña.

The summer JJA 500 mb pattern most closely resembled the weaker MEI El Niño composite. Nothing like the one that proceeded the strongest El Niños. So the higher ACE and 500mb pattern both conformed with the weaker MEI. But the warmer climate allowed for parts of the U.S. to have one of their warmest summers on record. So the past cooling influence during developing El Niño summers was muted. Also a smaller Aleutian Low than both El Niño composites. JJA 2023 pattern -EPO+PNA record south based -AO Weaker MEI composite -EPO+PNA-AO Strong MEI summer composite weak blocking and strong Aleutian Low

September was actually a mixed bag of competing or overlapping El Niño and La Niña influences. The strong ridge south of the Aleutians and trough over Alaska was classic La Niña. But the ridge north of the GL and NE was more Nino-like. September 2023 La Niña September with strong +SOI September El Niño composite

Who said anything about the entire month of October based on a 5 day snapshot for the start of the month? Just pointing out that the guidance has mixed influences to start the month. It could also be the seasonal shift from September to October early on. In any event, those two composites I posted for October will give us a real time updates as to which influences are at play. We would prefer to see the El Niño really taking charge with models correcting stronger with the -EPO +PNA October composite. But more of a ridge north of Great Lakes and weaker Aleutian low to the SW of the island chain would signal that the El Niño is still struggling to couple.

Looks like a hybrid Nino-Niña pattern to start October. We get the Niña-like Aleutians ridge and downstream ridge north of the Great Lakes. Then the El Niño influence of the height rises over NW Canada. But the typical Nino-like Aleutian Low is pretty much absent through the start of the month. So this goes to a tug of war pattern between competing influences. EPS forecast La Niña October +SOI composite El Niño October composite

The wet foliage this month at the ASOS is really keeping those departures artificially low. Stations will need to hold +1.8 to +2.0 to qualify for a top 10 warmest. So relatively small departures are all that’s needed with the jump in the 91-20 climate normals. EWR…+3.9 LGA….+2.3 NYC….+2.0 JFK…..+2.9 HPN…..+3.4 BDR……+2.2 HVN…..+5.2 ISP……..+3.3 PHL…….+3.3 POU…….+3.1

Those SSTs are just ridiculous. Like something we see during a strong -PDO. But we usually don’t get the warm extension to the Baja like we have now. So it’s driving the -PDO to the lowest level of -2.35 ever for a an El Niño with 3.4 over 1.5 in September. I think this is why the Euro and CFS are trying to really crank the Niña-like Aleutian Ridge in December. https://s2s.worldclimateservice.com/climatepanel/

The 2nd week was pretty warm also with mid 80s several days to low 90s one day. We didn’t get our first slightly cooler departure day until the 15th.

They called it a warming hole as there were some localized areas that had less warming or close to no trend over a specified period than if you averaged out the whole region. These pop up from time to time on a very localized global basis. The corn belt in the summer is another famous one and the blue blob south of Greenland.

The rate of warming in the SE during the winter is roughly half that of the Northeast. So you were able to sneak a top 10 coldest coldest as recently as 09-10. The Northeast has warmed too much to challenge a top 10 coldest. Been a bunch of papers written on the SE winter warming hole which shifts to the corn belt during the summer.

First, I have no use for politics as it currently exists in this polarized world. Second, would never suggest a policy measure or correction which would put more financial pressure on people in this age of high inflation. So my ideas and the studies I present are presented in order to refine our forecast capability. Not because I want to see some political solution to climate change. None probably exist anyway at the current time without some giant leap in the energy generating technology necessary to drive and sustain our planet. So we are essentially stuck with the carbon based economy for the time being. My comment on the general cold bias of models and seasonal forecasts wasn’t meant to be a jab at you. It was in response to what you said to me. I actually have a lot of respect for anyone willing to stick there neck out and make a detailed well though out seasonal forecast.

I am not ignoring anything. But thank you for giving the opportunity to clarify a few points. The -PNA -NAO from January into February 2021 followed the strong +PNA earlier that winter. The south based block in December 2020 was mitigated to an extent by the +PNA. But the height rises east of New England forced the storm formation further west giving BGM the record 40” jackpot instead of closer to the coast. It also resulted in the flood cutter on Christmas. So when the PNA shifted later on, the weak +PNA trough which was over the SE in December moved into the 50/50 slot. So there was definitely a +PNA assist from earlier in the season for that -PNA -AO pattern. Two very strong south based blocks in December 2020 and 2022. Not to mention the other record south based blocks during different months of the year. The PNA trough was weaker in January as a result.

Of course there are going to be variations. But the very nature of the variations can also change as the climate warms. Natural internal variability doesn’t exist in a vacuum.The -PNA -NAO patterns of the old days were colder and snowier in the Northeast than last winter. The -PNA trough last winter was weaker than was typical in the 50s to early 70s. So the issue last winter was the Greenland block building too far south in December. Those height rises east of New England were absent in the older era which I showed earlier in this thread under -PNA -NAO patterns. So expanding the ridges associated with blocks alters the storm track enough to make a big difference in the Northeast. All it takes in our area is a 50 to 200 mile shift in the storm track. That may not be a big deal on a continental to hemispheric teleconnection map .But it’s everything if the storm tracks west of NYC instead of out near the benchmark for people in our area.

Variations whether you call them cyclical, teleconnections, or oscillations all exist in a warmer climate state than they used to. So they aren’t immune from alterations or adjustments to reflect the warmer world. You are the one using terms like infantile and BS so maybe you are emotionally attached to colder winters from the past. That’s OK as long as you don’t let it influence your forecasting. I have offered many ideas about seasonal forecasts in too many threads to count. Just because I don’t offer a formal forecast each year isn’t a big deal. But I have successfully identified winter features in the fall that have worked out.

Off course you call BS since you look for a myriad of excuses to explain your way out of why the seasonal forecasts since 15-16 have all been biased too cold in the Northeast. Not sure why acknowledging that we have shifted into a warmer climate state is so hard for you. Again, this doesn’t mean that we won’t have colder winters at times again in the future. But even the colder run of winters at times from time to time from 02-03 to 14-15 were no match for the winters which were really cold from the late 70s to early 90s. Now if you want to ascribe it to some underlying cycle, the cycle was much colder in the late 70s to early 90s than 02-03 to 14-15. Plus the warming cycle since 15-16 was warmer than any earlier warmer periods by a large degree. So if we eventually swing back to another era like 02-03 to 14-15 in regard to colder winters making a comeback, chances are they won’t be as cold as some of those winters were. Our coldest Northeast winters since 02-03 were no match for the cold experienced from the late 70s to early 90s. 76-77…..18.4….5th coldest average winter temperature 77-78…..19.5 ..10th coldest 93-94….19.7…..11th coldest 78-79….20.7….18th coldest 14-15….20.8….19th coldest 02-03…20.9…20th coldest 13-14….22.1…..29th coldest.

The NE being the warmest part of the country over the last several years has plenty to do with the warming climate. Recent studies found as the WPAC heats up due to continued warming, we get more frequent MJO 4-6 phases which pumps the SE Ridge. Also slowing AMOC linked to warming climate causes warmer waters to pile up in the NW Atlantic. So it shifts the odds to warmer teleconnection patterns for us. Now this doesn’t mean that we won’t see another cold winter in the future. Or that we won’t see a shift to some new MJO state as the planet warms. But there is little doubt that the last 8 record warm seasons has had a robust warming climate signal.

More than some is due to warming. Any cold regressions in the future will be tempered by the warmer background state. But we should eventually see another colder winter again. Absent some massive volcanic eruption, a top 10 coldest winter like 76-77 simply isn’t possible anymore in this climate.

The one common denominator to all the winters since 15-16 has been the warmth in the Northeast. We have never seen an 8 winter stretch this warm before. But at least we have had some really good snowfall outcomes. 17-18 was trying to break the trend before the historic 80° warmth arrived in February around NYC. https://www.ncei.noaa.gov/access/monitoring/climate-at-a-glance/regional/time-series/101/tavg/3/2/1895-2023?base_prd=true&begbaseyear=1901&endbaseyear=2000 Warmest winter Northeast average temperature rankings since 15-16 30.7….2nd warmest temperature…..22-23….15-16 29.5….5th warmest temperature……16-17 28.9….6th warmest temperature…..19-20 27.1…..13th warmest temperature….20-21 26.1…..20th warmest temperature….21-22 25.6….23rd warmest temperature….18-19 25.3….26th warmest temperature…..17-18

Even with the closer to average last week against the warmer climate normals, the first 3 weeks of September have still finished top 5 warmest with widespread +3 to +5 departures. https://www.nrcc.cornell.edu/wxstation/perspectives/perspectives.html

The record breaking Hudson Bay block will really slow this down.