PhiEaglesfan712

The first week of December in 2007 was the best of that month, in regards to cold and snow. The snowstorm on the 5th was the best event until February 22nd. Although, the previous month (November) was colder than average. 2008 got going in the 2nd half of November, with a snowstorm on November 20. Again, the previous month (October) was colder than average. Weird thing about this winter is that the cold and snow didn't really align. October-January was the cold part, but the big storm was on March 1-2 (that was the beginning of about 6-7 years of great storms).

With the exception of 2017-18 and January 2022, the coastal areas haven't really had great snow since the mid-2010s el nino. Here is Atlantic City: 2016-2017 0.0 0.0 0.0 0.0 T T 7.2 0.3 0.2 0.0 0.0 0.0 7.7 2017-2018 0.0 0.0 0.0 0.0 0.0 10.0 14.5 T 9.6 T 0.0 0.0 34.1 2018-2019 0.0 0.0 0.0 0.0 T 4.8 4.9 6.9 1.2 0.0 0.0 0.0 17.8 2019-2020 0.0 0.0 0.0 0.0 T 0.5 T T 0.0 0.0 0.0 0.0 0.5 2020-2021 0.0 0.0 0.0 0.0 0.0 T 1.0 6.3 0.0 0.0 0.0 0.0 7.3 2021-2022 0.0 0.0 0.0 0.0 T T 33.2 0.1 T 0.0 0.0 0.0 33.3 2022-2023 0.0 0.0 0.0 0.0 0.0 T T 0.3 T 0.0 0.0 0.0 0.3 2023-2024 0.0 0.0 0.0 0.0 0.0 T 5.9 1.4 T 0.0 0.0 0.0 7.3 2024-2025 0.0 0.0 0.0 0.0 0.0 T 6.0 7.9 0.0 0.0 0.0 0.0 13.9

05-06 and 20-21 are la nina years that had a colder/snowier February than January.

https://www.severe-weather.eu/long-range-2/la-nina-has-formed-winter-2025-2026-latest-impacts-el-nino-reversal-united-states-canada-europe-fa/

Whether or not you use ONI or RONI, if you ignore what went on in Nino 1+2 last winter, then you're totally missing the picture. Last winter wasn't going to behave like a traditional la nina, or even a cold-neutral, with that warm eastern basin.

1949-51 la nina -> 1951-52 moderate el nino (yes, also continued in 1952-54) 1954-57 la nina -> 1957-58 strong el nino (yes, also continued in 1958-59) 1970-72 la nina -> 1972-73 super el nino (yes) 1974-76 la nina -> 1976-77 & 1977-78 moderate el nino (yes) 1983-85 la nina -> 1986-88 strong el nino (yes) 1988-90 la nina -> 1991-92 strong el nino (yes) 1998-2001 la nina -> 2002-03 moderate el nino (yes) 2007-09 la nina -> 2009-10 strong el nino (yes) 2010-12 la nina - no el nino in 2012-13 or 2013-14 (though we did get a super el nino in 2015-16) 2016-18 la nina -> 2018-19 weak el nino (no) 2020-23 la nina -> 2023-24 strong el nino (yes) So, within 2 years of a multi-year cold ENSO (at least one year la nina), we have: 1 no el nino (and this one eventually produced a strong el nino) 1 weak el nino 3 moderate el nino 5 strong el nino 1 super el nino Plus, 4 of these events were multi-year el ninos (1951-54, 1957-59, 1976-78, and 1986-88).

4 of the last 5 actually, as 09-10 was another strong el nino (along with 15-16 and 23-24). Very possible we could have a repeat of 86-89 (remember this came quickly after the 82-83 el nino), with the double el nino in 26-28, then transition to a strong la nina in 28-29. We're overdue for a strong la nina as well. We haven't had one since 10-11, which is the longest stretch without a strong la nina since 55-56 to 73-74. If we don't have a la nina by 28-29, we would have our longest stretch without a strong la nina since 1916-17 to 1955-56.

February 2006 wasn't all that bad. At least we got a return to cold, and a snowstorm on the 11th-12th. I'd gladly sign up for that after the last 3 or 4 winters. But please, no repeat of 1989-90, when spring pretty much began in January.

12/19/2009 to 2/10/2010 is the only one that really rivals 10-11. I highly doubt we're ever going to have a stretch with so much snow in very little time like those two winters. If we're going to have a high snow season, it will be more sustained throughout the season, like 2013-14 or 2014-15.

Yeah, people forget about that cool down in the last third of March 2011. Turned a solidly positive temperature departure to a near normal. I feel like the previous winter (2009-10) was more abrupt. Baltimore had 80 inches of snow by February 10, and the snow just stopped. The change was so dramatic, to the point there was record 90-degree heat during the first week of April. It's amazing, though, how so much snow was able to fall in such a short time during those 2 winters. And in 2 very different ENSO states (2009-10 being a strong el nino, and 2010-11 being a strong la nina).

And don't forget about Nino 1+2. That was in el nino mode all winter long.

Atlanta once recorded a -41.4 temperature departure in November 1950: 1950-11-25 17 3 10.0 -41.4 55 0 T T T

Anyone know where NOAA moved their ENSO ONI product? All I know is that the ASO value is -0.5 from this: https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

83 is also a +PDO, and so was 95. They can be thrown out. 1955, 1973, and 2010 were strong la ninas. They can be thrown out as well. 1950 and 2000 are the only analogs that make sense on that list.

The 2003-05 period is going to be nearly impossible to replicate, in terms of ACE. We had the one-year ACE (2005), two-year ACE (2004-05), and 3-year ACE (2003-05) records set. Also, most Cat 5 storms in one year (2005) and 5 years (2003-07), and until it was tied these last few years, the 2-year, 3-year, and 4-year Cat 5 records. (The 5-year record can be tied next year with one, and broken with 2.) I'd even argue that the record stretch began in 1998, maybe even 1995. We had six 175+ ACE seasons in 11 years from 1995-2005. In the 20 years since, we've only had 2 (2017 and 2020).

And don't forget that we also got the volcanic cooling from Pinatubo, which helped fueled the snowy winters of 92-93, 93-94, and 95-96. Then again, it's highly unlikely we're going to get something like Pinatubo the rest of this decade. So, we're going to have to hope this next el nino flips the PDO positive or the Pacific jet becomes slow again (like 2009-10/2010-11 or 2013-14/2014-15). Are you sure the PDO is -1.31? I see -2.40 as the value for October 2025 (actually lower than the -2.33 in September) on NOAA: https://www.ncei.noaa.gov/pub/data/cmb/ersst/v5/index/ersst.v5.pdo.dat

The only "fast starts to winter, then died in January" were 89-90 and 07-08. Technically, you could argue 05-06 and 20-21, but those had a blockbuster return in February.

ASO 2025 RONI: -0.78

14-15 had a cold November, though. It was more like December was the outlier warm month. I think that had to be 90-91. That was a wall-to-wall warm winter, which continued into spring and summer. Almost like a 11-12 redux.

Should be February 22, 1929. Also, if NYC doesn't get a 10-inch snowstorm, it will be the 9th out of 10 seasons without a 10-inch snowstorm (only 2020-21 had a snowstorm >10 inches). I think it will be the first time that NYC hasn't had a 10-inch snowstorm 5 years in a row, breaking a tie with 2016-17 to 2019-20.

The thing I worry about with your composite is that in those 3 years (2011, 2016, and 2021), only one of the 9 winter months that followed (January 2022) produced a good cold and snowy month. The rest of the months were blowtorches.

I think 2017 is the only exception, with the historic cold 2nd half of December/first half of January. We stayed overnight (might have been 2 nights) at AC for my sister's 25th birthday, and it was way too cold to go on the Boardwalk. That year, we didn't get the warm-up until mid-January, and we all know about that record warmth in February. Then, of course, the cold/snowy pattern came back for March and April.

Wait, the 1991-2020 average is only 122? I thought it would be somewhere around 140, considering how active 1995-2005 was. I guess I can lower the baseline for a hyperactive season to 175. That will give us 13: 1 2005 247.65 2 1933 235.785 3 1893 231.0738 4 1995 227.5513 5 1950 227.1413 6 2004 226.94 7 1926 225.7788 8 2017 224.8775 9 1961 196.95 10 1998 181.8838 11 2020 180.3725 12 1955 178.585 13 1999 177

2017-18 and January 2022 are the only times really that the coastal areas got good snow since the mid-2010s el nino. But 2009-10 to 2015-16 (if you take out 2011-12 and 2012-13) was a great run for the coastals (this is Atlantic City's snowfall): 2009-2010 0.0 0.0 0.0 0.0 0.0 12.6 8.9 36.6 T 0.0 0.0 0.0 58.1 2010-2011 0.0 0.0 0.0 0.0 0.0 20.9 13.4 3.7 T 0.0 0.0 0.0 38.0 2013-2014 0.0 0.0 0.0 0.0 T 3.3 18.8 6.1 15.6 T 0.0 0.0 43.8 2014-2015 0.0 0.0 0.0 0.0 T 0.4 4.8 9.8 7.4 0.0 0.0 0.0 22.4 2015-2016 0.0 0.0 0.0 0.0 0.0 0.0 16.7 3.9 5.1 1.8 0.0 0.0 27.5