bluewave

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.

West Point getting close to a top 10 wettest year. Time Series Summary for WEST POINT, NY - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 2011 80.37 0 2 1996 71.39 1 3 1983 69.49 0 4 2018 69.16 1 5 2005 67.72 1 6 2003 65.60 0 7 1952 65.01 0 8 1979 62.26 2 9 1972 59.74 0 10 1975 58.85 0 11 2010 58.04 0 12 1990 57.81 1 13 1994 56.93 0 14 2023 56.70 99

NYC is on track for another 50”+ year with numerous sites around the area already over 50”. Data for January 1, 2023 through October 6, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation CT SEYMOUR 1.2 WSW CoCoRaHS 57.56 NY WEST POINT COOP 56.70 CT ANSONIA 1 NE COOP 53.38 CT PROSPECT 1.9 ENE CoCoRaHS 53.11 NY PEEKSKILL 0.4 N CoCoRaHS 52.92 NY STONY POINT 0.7 NW CoCoRaHS 52.56 CT NORWICH 2.5 NNE CoCoRaHS 52.48 NY THORNWOOD 0.7 NW CoCoRaHS 51.99 CT NORTHFORD 0.8 SW CoCoRaHS 51.99 CT EAST LYME 0.5 SW CoCoRaHS 51.82 CT WATERBURY 1.3 WNW CoCoRaHS 51.72 NY NEW HEMPSTEAD 0.6 SE CoCoRaHS 51.51 CT BROOKFIELD 3.3 SSE CoCoRaHS 50.76 CT GRISWOLD 0.9 N CoCoRaHS 50.61 NY SHRUB OAK COOP 50.59 NY BEACON 4.2 ESE CoCoRaHS 50.37 CT MIDDLEFIELD 0.6 SE CoCoRaHS 50.14 CT PROSPECT 0.5 SW CoCoRaHS 50.00 CT NAUGATUCK 1.7 NNE CoCoRaHS 49.50 NY CARMEL 4N COOP 49.46 CT MERIDEN 2.8 WSW CoCoRaHS 49.39 NY SOUTH SALEM 2.1 NW CoCoRaHS 49.26 CT BETHANY 1.3 SW CoCoRaHS 49.26 NY PORT JERVIS 2.9 ESE CoCoRaHS 49.22 NY SOUTH SALEM 0.8 N CoCoRaHS 49.10 CT COLCHESTER 0.6 ENE CoCoRaHS 48.99 CT NEWTOWN 4.6 SE CoCoRaHS 48.98 CT HIGGANUM 0.8 NE CoCoRaHS 48.68 CT DURHAM 1.2 W CoCoRaHS 48.64 CT WALLINGFORD CENTER 1.9 WNW CoCoRaHS 48.62 CT RIDGEFIELD 2.4 NNE CoCoRaHS 48.35 CT NEW CANAAN 1.9 ENE CoCoRaHS 48.17 NY BROOKLYN 3.1 NW CoCoRaHS 48.10 NY ELMSFORD 0.8 SSW CoCoRaHS 48.09 NY ARMONK 0.3 SE CoCoRaHS 48.05 CT OAKDALE 2.6 WNW CoCoRaHS 47.88 NJ RINGWOOD 3.0 SSE CoCoRaHS 47.73 CT HIGGANUM 0.7 N CoCoRaHS 47.50 NY PINE BUSH 3.4 WSW CoCoRaHS 47.34 NJ WAYNE TWP 2.3 ESE CoCoRaHS 47.31 CT SOUTHBURY 2.3 W CoCoRaHS 47.25 NY LITTLE NECK 0.3 SE CoCoRaHS 47.15 CT JEWETT CITY 3.0 ESE CoCoRaHS 47.10 CT WALLINGFORD CENTER 3.3 NNW CoCoRaHS 46.92 CT SHELTON 1.3 W CoCoRaHS 46.62 CT NORWALK 1.4 ENE CoCoRaHS 46.48 CT OLD LYME 3.4 ESE CoCoRaHS 46.42 CT BETHEL 0.5 E CoCoRaHS 46.33 CT RIDGEFIELD 3.6 N CoCoRaHS 46.13 NJ GLEN ROCK 0.7 SSE CoCoRaHS 46.12 NY LAGUARDIA AIRPORT WBAN 46.00 CT OXFORD WATERBURY WBAN 45.98 CT MONROE 0.8 W CoCoRaHS 45.98 CT NEW CANAAN 3.8 N CoCoRaHS 45.97 CT NORWALK 2.9 NNW CoCoRaHS 45.90 CT SALEM 3.6 SE CoCoRaHS 45.78 NY NY CITY CENTRAL PARK WBAN 45.73

https://iopscience.iop.org/article/10.1088/1748-9326/ac5edf/meta The Indo-Pacific warm pool (IPWP) has warmed and expanded substantially over the past decades, which has significantly affected the hydrological cycle and global climate system. It is unclear how the IPWP will change in the future under anthropogenic (ANT) forcing. Here, we quantify the human contribution to the observed IPWP warming/expansion and adjust the projected IPWP changes using an optimal fingerprinting method based on Coupled Model Intercomparison Project phase 6 (CMIP6) simulations. We find that more than 95% rapid warming and 85% expansion of the observed IPWP are detected and attributable to human influence. Furthermore, human activities affect IPWP warming through both greenhouse gases and ANT aerosols. The multiple model ensemble mean can capture the ANT warming trend and tends to underestimate the ANT warming trend. After using the observation constraint, the IPWP warming is projected to increase faster than that of the ensemble mean in the 21st Century, and the Indian Ocean warm pool is projected to expand more than previously expected. The rapid warming and expansion of IPWP over the rest of the 21st century will impact the climate system and the life of human beings.

The best October correlation that I have found since 2010 only works during La Ninas. The stronger MJO 4-6 Octobers during La Ninas had better seasonal snowfall around NYC. It’s a shorter period than we like to use for correlations but I got lucky using it during the the fall of 2020 in one of the old threads.

I wonder what it would be like to run a global system like that out to 360 hrs as an ensemble mean. I have read they want to upgrade the ECMWF EPS to 4-5 km closer to convection allowing resolution.

Interesting…thanks for posting. https://gsl.noaa.gov/focus-areas/unified_forecast_system/rrfs Within the NOAA model unification effort, the RRFS represents the evolution of the NAM, RAP, HRRR, and HREF systems to a new unified deterministic and ensemble storm-scale system. This new system is targeted for initial operational implementation in late 2024 as a planned replacement for the NAMnest, HRRR, HiResWindows, and HREF. While the standalone regional (SAR) FV3 model is being developed for convection-allowing forecasting of a limited area (CONUS), other possible components of the RRFS are being tested now in the experimental, WRF-based High-Resolution Rapid Refresh Ensemble (HRRRE). Experimental runs of the HRRRE at GSL are focused particularly on: Improving 0-12 h high-resolution forecasts through ensemble-based, multi-scale data assimilation Producing spread in 0-36 h ensemble forecasts through initial-condition perturbations, boundary-condition perturbations, and stochastic physics.

It’s a bit of an October reversal like we see with the MJO 4-6 being colder in October than the winter.

The big MEI mismatch continues with AS only coming in at +0.6. Doesn’t match any of the other AS cases with Nino 3.4 in the borderline moderate to strong range. https://psl.noaa.gov/enso/mei/

The real test will come during the winter since a stronger Aleutian low in October is more Niña-like than Nino-like. It’s one of those interesting monthly correlation shifts that we see from time to time. It’s one of the few times of the year when a La Niña or -PDO produce a trough near the Southeast.

We probably have to take the warmer trend more seriously than we usually do with these seasonal forecasts since it matches the winter pattern of warmer East and colder West since the super El Niño in 15-16.