bluewave

While the SST maxes in 86-87 were split between 3.4 and 1.2, the actual forcing was pretty far west. So there were elements of that winter than could be called Modoki-like. It was the snowiest winter of the 1980s in Central NJ Data for October 1, 1986 through April 30, 1987 Click column heading to sort ascending, click again to sort descending. Name Station Type Total Snowfall SUSSEX 1 NW COOP 70.0 LAKEHURST NAS WBAN 65.0 HIGH POINT PARK COOP 53.9 ESTELL MANOR COOP 48.1 NEW BRUNSWICK 3 SE COOP 47.3 New Brunswick Area ThreadEx 47.3 POTTERSVILLE 2 NNW COOP 46.1 OAK RIDGE RESERVOIR COOP 45.5 INDIAN MILLS 2 W COOP 45.4 HIGHTSTOWN 2 W COOP 44.8 NEWTON COOP 44.5 CHARLOTTEBURG RESERVOIR COOP 44.0 GREENWOOD LAKE COOP 43.5 MILLVILLE MUNICIPAL AIRPORT WBAN 43.2 MORRIS PLAINS 1 W COOP 41.9 Time Series Summary for New Brunswick Area, NJ (ThreadEx) Click column heading to sort ascending, click again to sort descending. Ending Date Total Snowfall Oct 1 to Apr 30 Missing Count 1980-04-30 21.5 0 1981-04-30 21.2 0 1982-04-30 30.9 0 1983-04-30 34.6 0 1984-04-30 37.7 0 1985-04-30 25.8 0 1986-04-30 24.6 0 1987-04-30 47.3 0 1988-04-30 25.3 0 1989-04-30 10.5 0

It’s probably related to the warming of the climate since the 97-98 super El Niño. https://www.nature.com/articles/s41558-019-0663-x The Pacific Decadal Oscillation less predictable under greenhouse warming Abstract The Pacific Decadal Oscillation (PDO) is the most prominent form of decadal variability over the North Pacific, characterized by its horseshoe-shaped sea surface temperature anomaly pattern1,2. The PDO exerts a substantial influence on marine ecosystems, fisheries and agriculture1,2,3. Through modulating global mean temperature, the phase shift of the PDO at the end of the twentieth century is suggested to be an influential factor in the recent surface warming hiatus4,5. Determining the predictability of the PDO in a warming climate is therefore of great importance6. By analysing future climate under different emission scenarios simulated by the Coupled Model Intercomparison Project phase 5 (ref. 7), we show that the prediction lead time and the associated amplitude of the PDO decrease sharply under greenhouse warming conditions. This decrease is largely attributable to a warming-induced intensification of oceanic stratification, which accelerates the propagation of Rossby waves, shortening the PDO lifespan and suppressing its amplitude by limiting its growth time. Our results suggest that greenhouse warming will make prediction of the PDO more challenging, with far-reaching ramifications.

The only current analog for March into April significant warmth in the EPAC and cooler Nino 3.4 is March 2017. But the subsurface across the Pacific has more of a developing El Niño signature than that year. The Euro was forecasting a moderate El Niño that year which never verified. So not many good analogs yet for this one. https://www.frontiersin.org/articles/10.3389/fmars.2018.00367/full The latest extreme coastal El Niño occurred in austral summer 2017. A strong surface temperature anomaly developed off northern Peru, reaching a maximum of +5°C at the coast, while very weak temperature anomalies were found in the Central Equatorial Pacific (Figure 1). Coastal precipitations attained a maximum of 8 mm day-1(monthly average), thus being almost as intense as during the 1997–98 El Niño event (10 mm day-1, Figure 1). The event was triggered by a decrease of the southerly trade winds in January 2017 (Figure 2A) which reduced the latent heat release and ocean cooling (Garreaud, 2018; Hu et al., 2018). Climate reanalysis data suggest that the wind relaxation was related to the weakening of the free tropospheric westerly flow impinging the subtropical Andes, remotely forced by anomalously intense deep convection in the western Pacific (Garreaud, 2018). However, the impacts of the wind relaxation and local air-sea feedbacks on the coastal upwelling have not been investigated in detail.

The difference between this event so far and 82-83 and 97–98 is the big spread between Nino 1+2 and 3.4. So it’s much more east based than those events early on. It looks like a result of the weaker WWBs in the Central Pacific. Nino 3.4 is still neutral while 1.2 has been near +2 in recent weeks. When 1.2 first reached +2 in 82-83 and 97-98, 3.4 was already above +0.5 and into Nino territory. So the WWBs will need to pick up down the road for more significant warming in 3.4. The other difference is that the PDO Is currently even lower than in the beginning of the 72-73 El Niño. That one also had stronger CP WWBs early on than this year with more Nino 3.4 warming when 1+2 reached +2. So this event seems to be unique in its early development. Perhaps the anomalous WPAC warm pool and strong -PDO are slowing the CP WWB response and allowing the WWBs to be more east based than usual. Still early in the game so things can change. https://www.cpc.ncep.noaa.gov/data/indices/sstoi.indices https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/index/ersst.v5.pdo.dat

The PDO intervals were much longer from 1950 to 1998. We had multi decade long +and - phases .Notice the rapid shifts after 5-7 years following the 97-98 super El Niño.

Very impressive backdoor pushing through the Southeast. https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G16&sector=se&band=GEOCOLOR&length=24

The Central Pacific Trade Wind Index was stronger this March than before the the 82-83, 97-98, and 15-16 events. So the WWBs were displaced closer to the EPAC than in March those years. The stronger event years began with much stronger WWBs in the CPAC. This event is featuring very strong east based warming in March which took longer to occur in even east based years like 97-98. Not sure what if any influence this will have on the ultimate strength and location of the warmest SST anomalies later on. But the CPAC trades will need to relax in the coming months if this is to become a stronger event. Still early in the game so a lot can change. https://www.cpc.ncep.noaa.gov/data/indices/cpac850 850 MB TRADE WIND INDEX(175W-140W)5N 5S CENTRAL PACIFIC ANOMALY 2023 3.4 3.7 1.6 2015 -2.1 -1.2 -0.6 1997 -0.6 2.2 -1.6 1982 0.8 -0.8 -0.9

Great pattern for record snow in the West.

While those storms dropped below severe levels when they came through Long Beach around midnight, it was the only time I experienced continuous lightning living here on Long Island.

This a list but some events could be missing. https://medium.com/@CC_StormWatch/tornadoes-in-the-northeast-not-as-rare-as-you-think-75470d533eae June 9, 1953 — Worcester, MA EF-4 tornado, resulted in 90 deaths and over 1,000 injuries, by far the worst Northeast tornado Storm Events Database Event Details: https://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=10080366 Event Tornado Magnitude 0 -- Scale F3 -- Length .4 Miles -- Width 50 Yards State NEW JERSEY County/Area MORRIS NCEI Data Source PUB Begin Date 1973-05-28 18:55 CST October 3, 1979 — Windsor Locks, CT EF-4 tornado, resulted in 3 deaths https://bigfrog104.com/33-years-ago-this-week-an-f3-tornado-touchdown-in-boonville-video/ On May 2nd, 1983 an F3 tornado and other storms ripped through and ravaged 11 New York counties. People were killed, several were injured, and there was detrimental property damage. On this week 33 years later, we remember that day with this Raw Footage from Matt Lanza who worked at WKTV at the time. May 1985 https://www.weather.gov/ctp/TornadoOutbreak_May311985 On the evening of May 31st, 1985, a devastating and deadly tornado outbreak struck the Northeastern United States and Canada. 43 tornadoes and numerous damaging thunderstorms tore across Ohio, Pennsylvania, New York, and Ontario. This event was the deadliest tornado outbreak of the 1980's; killing 89 people in total, injuring more than 1,000 others, and racking up more than $600 million in property damage. In fact, since May 31, 1985, only two tornado days have been deadlier in the entire United States. Storm Events Database Event Details: https://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=10082624 Event Tornado Magnitude 0 -- Scale F3 -- Length .2 Miles -- Width 10 Yards State NEW JERSEY County/Area OCEAN NCEI Data Source PUB Begin Date 1983-07-21 19:30 CST Begin Location 0 July 10, 1989 — Tornado outbreak Multiple EF-2 to EF-4 tornadoes, including in New Haven, CT and near Albany, NY, no deaths but many injuries Storm Events Database Event Details: https://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=10080366 Event Tornado Magnitude 0 -- Scale F3 -- Length .5 Miles -- Width 100 Yards State NEW JERSEY County/Area SOMERSET NCEI Data Source PUB Begin Date 1990-10-18 17:07 EST Begin Location 0 May 31, 1998 — Tornado outbreak Multiple EF-2 and EF-3 tornadoes in several states, including NY and PA, resulted in 5 deaths and many injuries June 2, 1998 — Tornado outbreak Two days later, multiple tornadoes up to EF-4 in NY, PA and MD, resulted in 2 deaths September 24, 2001 — College Park, MD EF-3 tornado, resulted in 2 deaths and over 60 injuries April 28, 2002 — La Plata, MD EF-4 tornado, resulted in 5 deaths and many injuries June 1, 2011 — Springfield/Monson, MA EF-3 tornado, resulted in 3 deaths and 200+ Update on August 1, 2021: at least 9 tornadoes touched down in the NWS Mount Holly area, including southeastern Pennsylvania and central and southern New Jersey. They included an EF-3 tornado in Bucks County, PA (in the Philadelphia suburbs). Storm Events Database Event Details: https://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=972306 Begin Date 2021-09-01 17:10 EST-5 Event Tornado -- Scale EF3 -- Length 12.37 Miles -- Width 400 Yards State NEW JERSEY County/Area GLOUCESTER WFO PHI Report Source NWS Storm Survey NCEI Data Source CSV

Looks like NJ tied the daily record.

Plenty of cold that year for record snow and cold into April. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1934 -14 0 2 1985 -8 0 - 1933 -8 0 3 1982 -7 0 - 1943 -7 0 Data for January 1, 1982 through January 31, 1982 Click column heading to sort ascending, click again to sort descending. Name Station Type Lowest Min Temperature TOMS RIVER COOP -19 MORRIS PLAINS 1 W COOP -16 HIGH POINT PARK COOP -15 BELLEPLAIN STA FOREST COOP -14 PEMBERTON COOP -14 INDIAN MILLS 2 W COOP -13 LAKEHURST NAS WBAN -13 SOMERVILLE 4 NW COOP -12 ESTELL MANOR COOP -12 EWING 3 WNW COOP -11 CHARLOTTEBURG RESERVOIR COOP -11 Trenton Area ThreadEx -11 LONG VALLEY COOP -10 ESSEX FELLS SERVICE BLDG COOP -10 NEWTON COOP -10 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1982 16 0 2 1995 23 0 - 1954 23 0 3 1943 24 0 Data for April 6, 1982 through April 6, 1982 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Snowfall NY ISLIP-LI MACARTHUR AP WBAN 16.0 NY PORT JERVIS COOP 15.1 NJ NEWARK LIBERTY INTL AP WBAN 12.8 NJ TETERBORO AIRPORT WBAN 12.0 NY WESTCHESTER CO AP WBAN 12.0 NJ LODI COOP 11.5 NY SCARSDALE COOP 10.2 NJ PLAINFIELD COOP 10.1 NJ MIDLAND PARK COOP 10.0 CT STAMFORD 5 N COOP 10.0 CT DANBURY COOP 10.0 NY DOBBS FERRY-ARDSLEY COOP 9.7 NY NY CITY CENTRAL PARK WBAN 9.6 Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Total Snowfall Missing Count 1 1982 16.0 0 2 1996 9.6 0 3 2003 5.0 0 4 2018 4.6 0 5 1990 3.0 0 Time Series Summary for Chicago Area, IL (ThreadEx) - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1985 -27 0 2 1982 -26 0 3 1983 -25 0 4 2019 -23 0 - 1872 -23 163 5 1984 -22 0 6 1994 -21 0 - 1899 -21 0 7 1897 -20 0 - 1875 -20 0

Seems like we have been getting shorter PDO intervals since 2000 with the ups and downs. Much different from the extended cold PDO in 50s to 70s. Also the positive periods much shorter than late 70s into 90s. https://psl.noaa.gov/data/climateindices/

Yeah, Dec 17-18 and Jan 21 were our only 30 day periods in 20s since 15-16. Minimum 30-Day Mean Avg Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Rank Value Ending Date Missing Days 1 27.2 2018-01-19 0 23 29.3 2022-02-02 0

Yeah, all Western and Central troughs since the 15-16 super El Niño.

Yeah, at some point the warm spots like Newark should at least make the mid 80s this month. Could be a little higher like several years since 2010. Especially with the -PNA and SE Ridge. I will laugh if we still that have that Western Trough next winter again even with an El Niño. Would have to be a strong enough -PDO like the 72-73 El Niño to pull that one off.

Yeah, April 1976 was the only time the warmest day of the year was in April. But 2009 was a tie. Both years were followed by memorable winters. Monthly Highest Max Temperature for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual 2002 69 63 72 96 86 92 96 98 91 84 68 60 98 1976 56 70 72 96 83 92 90 94 89 73 61 55 96 2010 57 46 74 92 92 93 103 96 96 75 65 60 103 2009 47 65 70 92 86 84 86 92 84 74 69 66 92 1915 58 58 59 92 79 90 93 89 94 79 71 57 94 1990 66 65 85 91 83 89 95 93 89 84 78 66 95 1962 56 56 79 91 99 93 96 91 88 85 62 68 99 1942 57 52 69 91 92 89 97 93 93 84 74 58 97 1991 55 70 77 90 93 97 102 94 93 80 74 66 102

Looks like some more thunderstorms. But not the steep mid-level lapse rates and high helicity values like the other day. So no big tornado outbreak. But we may get enough instability and shear for some straight line severe gusts. We’ll see if Philly to CNJ is the thunderstorm magnet again. Maybe the stronger warm sector can help push some of the bigger storms closer to I-78 to I-80 this time.

The AMOC slowdown pulls the Gulf Stream in closer to the Northeast and only cools a small part of the North Atlantic south of Greenland. In the North Atlantic, the measured values differ markedly from the average global warming: the subpolar Atlantic (an area about half the size of the USA, south of Greenland) has hardly warmed up and in some cases even cooled down, contrary to the global warming trend. In contrast, a wide area along the American east coast has warmed up at an excessive rate. Both can be attributed to a weakening of the AMOC in the model simulation. The cooling is simply due to the reduced heat input from the AMOC. The excessive warming, on the other hand, is based on a somewhat more nerdy mechanism that has been known to experts for some time: if the AMOC weakens, the Gulf Stream shifts closer to the coast. (This has to do with conservation of angular momentum on the rotating globe.) study by Duchez et al. (2016) shows that cold in the North Atlantic correlates with summer heat in Europe. This is due to the fact that the heat transport in the Atlantic has not yet decreased strongly enough to cause cooling also over the adjacent land areas – but the cold of the sea surface is sufficient to influence the air pressure distribution. It does that in such a way that an influx of warm air from the south into Europe is encouraged. In summer 2015, the subpolar Atlantic was colder than ever since records began in the 19th century – associated with a heat wave in Europe. Haarsma et al (2015) argue on the basis of model calculations that the weakening of the AMOC will be the main cause of changes in the summer circulation of the atmosphere over Europe in the future. Jackson et al (2015) found that the slowdown could lead to increased storm activity in Central Europe. And a number of studies suggest that if the AMOC weakens, sea levels on the US coast will rise more sharply (e.g. Yin et al. 2009). The impacts are currently being further researched, but a further AMOC slowdown cannot be considered good news. Yet, although the oscillations seen in Fig. 2 suggest the AMOC may well swing up again for a while, a long-term further weakening is what we have to expect if we let global warming continue for much longer.

Yeah, Canada sticks out further to the East. So they can catch many recurving systems that miss the US.

I believe it comes down to the steering currents during the hurricane season. Bob was the last New England hurricane back in 1991. All the high impact events like Sandy had the eye come ashore south of 40N. From what I can see, the much warmer SSTs have allowed the subtropical ridge to push up into New England and Eastern Canada. So the high impact hurricanes have all come in further down the coast. Like the hurricanes have been squeezing under. The Gulf has been the main focus for most of the landfalling major hurricanes in the last 30 years. During the previous 40, it was more evenly divided between Gulf and East Coast. https://www.aoml.noaa.gov/hrd/hurdat/All_U.S._Hurricanes.html 1991 Aug RI, 2; MA, 2; NY, 2; CT, 2 2 962 90 Bob 1992 Aug FL, SE5, SW4; LA, 3 5 922 145 Andrew 1993 Aug * NC, 3 3 961 100 Emily 1994 None 1995 Aug FL, NW2, SE1 2 973 85 Erin 1995 Oct FL, NW3, I-AL 1 3 942 100 Opal 1996 Jul NC, 2 2 974 90 Bertha 1996 Sep NC, 3 3 954 100 Fran 1997 Jul LA, 1; AL, 1 1 984 70 Danny 1998 Aug NC, 2 2 964 95 Bonnie 1998 Sep FL, NW1 1 987 70 Earl 1998 Sep FL, SW2; MS, 2 2 964 90 Georges 1999 Aug TX, S3 3 951 100 Bret 1999 Sep NC, 2 2 956 90 Floyd 1999 Oct * FL, SW1; NC, 2 2 964 95 Irene 2000s 2000 None 2001 None 2002 Oct LA, 1 1 963 80 Lili 2003 Jul TX, C1 1 979 80 Claudette 2003 Sep NC, 2; VA, 1 2 957 90 Isabel 2004 Aug * NC, 1 1 972 70 Alex 2004 Aug FL, SW4, SE1, NE1; SC, 1; NC, 1 4 941 130 Charley 2004 Aug SC, 1 1 985 65 Gaston 2004 Sep FL, SE2, SW1 2 960 90 Frances 2004 Sep AL, 3; FL, NW3 3 946 105 Ivan 2004 Sep FL, SE3, SW1, NW1 3 950 105 Jeanne 2005 Jul LA, 1 1 991 65 Cindy 2005 Jul FL, NW3; I-AL 1 3 946 105 Dennis 2005 Aug FL, SE1, SW1; LA, 3; MS, 3; AL, 1 3 920 110 Katrina 2005 Sep * NC, 1 1 982 65 Ophelia 2005 Sep FL, SW1; LA, 3; TX, N2 3 937 100 Rita 2005 Oct FL, SW3; FL, SE2 3 950 105 Wilma 2006 None 2007 Sep TX, N1; LA, 1 1 985 80 Humberto 2008 Jul TX, S1 1 967 75 Dolly 2008 Sep LA, 2 2 954 90 Gustav 2008 Sep TX, N2; LA, 1 2 950 95 Ike 2009 None 2010s 2010 None 2011 Aug NC, 1 1 952 75 Irene 2012 Aug LA, 1 1 966 70 Isaac 2012 Oct * NY, 1 1 942 65 Sandy 2013 None 2014 Jul NC, 2 2 973 85 Arthur 2015 None 2016 Sep FL, NW1 1 981 70 Hermine 2016 Oct * FL, NE2; GA, 1; SC, 1; NC, 1 2 963 85 Matthew 2017 Aug TX,C4 4 937 115 Harvey 2017 Sep FL, SW4,SE 1 4 931 115 Irma 2017 Oct LA 1, MS 1 1 983 65 Nate 2018 Sep NC, 1 1 956 80 Florence 2018 Oct FL, NW5; I-GA, 2 5 919 140 Michael 2019 Jul LA, 1 1 993 65 Barry 2019 Sep NC, 2 2 956 85 Dorian 2020s 2020 Jul TX, S1 1 973 80 Hanna 2020 Aug NC, 1; SC, 1 1 986 80 Isaias 2020 Aug LA, 4; TX, N1 4 939 130 Laura 2020 Sep AL, 2; FL, NW2 2 965 95 Sally 2020 Oct LA,2 2 970 85 Delta 2020 Oct LA,3; MS, 2; I-AL, 1 3 970 100 Zeta 2021 Aug LA,4 4 931 130 Ida 2021 Sep TX,N1 1 991 65 Nicholas

Same goes for the PNA. We used to get much more negative values back in the 1950s to the 1970s. March was the deepest the trough got this year.

The GOA SSTs are mostly a function of Rossby waves being driven from the subtropical and tropical parts of the Pacific. So record SSTs to the south of that area are probably driving that process. Same goes for the increasing SE Ridge or WAR in our region. A 7° increase in the Gulf Stream off the Mid-Atlantic subtropics can cause an expansion of the subtropical ridge into our area. Notice how the models consistently underestimate the SE Ridge in the day 11-15 forecast. Also look back at winter forecasts for the US from all the private and public forecasters. The seasonal maps have underestimated the warmth in area. So we have to look into changes with the Gulf Stream we see a very anomalous 8 warmer than average winters in a row for the Northeast.

This tweet gives another answer to your good question.

The March -2.35 -PDO was the lowest in March since 1956 when the reading was -2.93. March 2009 was the last time below -2 in March at -2.06. Near record trough along the West Coast driving the SST pattern. So these are the warmest SSTs anomalies near the coast of South America in March for such a cold PDO. https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/index/ersst.v5.pdo.dat