PhiEaglesfan712

To be fair, with the exception of the 2014-16 El Nino, we've been in an extended -PDO pattern ever since the spring of 1998 (when the super el nino of 1997-98 dissipated).

At least these upper 90s/100s are balancing out the mid-60s highs of last June 21/22.

Strong el ninos and 3-4 year aftermath (+ Year 5 if 3/4 are not strong el ninos) Bolded are years where strong el nino -> strong la nina transitions happened 1957-58: ENSO neutral, ENSO neutral (Year 5: ENSO neutral) 1965-66: Moderate el nino, weak el nino (Year 5: moderate la nina) 1972-73: Strong la nina, moderate el nino (Year 5: moderate el nino) 1982-83: ENSO neutral, moderate el nino (Year 5: strong el nino) 1987-88: ENSO neutral, strong el nino 1991-92: Moderate el nino, moderate la nina (Year 5: ENSO neutral) 1997-98: Weak la nina, neutral (Year 5: moderate el nino) 2009-10: ENSO neutral, ENSO neutral (Year 5: weak el nino) 2015-16: Weak el nino, maybe weak el nino (Year 5: moderate la nina) Year 3 aftermaths: 2/9 moderate el nino, 1/9 weak el nino, 4/9 ENSO neutral, 1/9 weak la nina, 1/9 strong la nina Year 4 aftermaths: 1/9 strong el nino, 2/9 moderate el nino, 5/9 weak el nino/ENSO neutral, 1/9 moderate la nina Year 5 aftermaths (exclude 1992-93): 1/8 strong el nino, 2/8 moderate el nino, 1/8 weak el nino, 2/8 ENSO neutral, 2/8 moderate la nina FWIW, the 1991-92 and 2009-10 Year 6 aftermaths resulted in the super el ninos of 1997-98 and 2015-16.

According to NWS Mt. Holly, average temperatures today are 2 degrees F warmer than in 1925: 2011 was the last time it passed 100 at Lehigh Valley International Airport. Despite that, the average temperature is still 2 degrees hotter than it was 99 years ago.

EURO got it right last year, but it's been a mixed bag the last 17 years. 9 years were clear misses. 6 years they got right (07, 09, 15, 18, 19, and 23). Two are on the fence, they hinted correctly at la ninas in 10 and 16, but ended up stronger than predicted: ’23 +2.04/+1.92/+1.49 - in range ’22 -0.25/-0.92/-1.03 - miss ’21 -0.30/-0.98/-1.21 - miss ’20 -0.49/-1.27/-1.52 - miss ’19 +0.67/+0.51/+0.24 - in range ‘18 +1.1/+0.9/+0.8 - in range ’17 +0.4/-0.8/-1.1 - miss ‘16 -0.4/-0.7/-1.1 - 50/50 (got the hint of a weak nina, but ended up stronger) ’15 +2.4/+2.6/+2.3 - in range ’14 +1.3/+0.6/+0.5 - miss ’13 +0.6/-0.2/-0.2 - miss ‘12 +1.2/+0.1/-0.1 - miss *’11 +0.1/-1.0/-0.9 - miss *’10 -1.0/-1.6/-1.7 - 50/50 (got the hint of a significant nina, but ended up stronger) *’09 +1.3/+1.0/+0.9 - in range *’08 +0.3/-0.4/-0.4 - miss *’07 -1.1/-1.3/-1.3 - in range

It's way too early to tell. 2026-27 could be a 3rd year la nina, a developing el nino, or even an enso neutral season. Here are the TS/H/M stats for all years 2 following the first year of a multi-year la nina: 1951 (developing moderate el nino): 12/8/3 1956 (3rd year la nina, weak): 12/4/1 1972 (developing super el nino): 7/3/0 1975 (3rd year la nina, strong): 9/6/3 1985 (enso neutral): 11/7/3 1990 (enso neutral): 14/8/1 2000 (3rd year la nina, weak): 15/8/3 2009 (developing strong el nino): 9/3/2 2012 (enso neutral): 19/10/2 2018 (developing weak el nino): 15/8/2 2022 (3rd year la nina, moderate): 14/8/2 Aside from 2012, a lot of average to below average seasons, even the ones that are a la nina. It seems like the enso neutral seasons overperform.

1995-96 and 2005-06 are examples of one year la ninas. Both were well above average hurricane seasons, with the latter setting all kinds of records.

I remember this blocking pattern. If only we can get something like this in winter:

lol, that's a nice blocking pattern in the Eastern US. Imagine if that was in place in any time between late December and March.

This prediction turned out to be wrong, as 2021 was a record breaking warm summer for most of the Western US.

We're finally getting that Eastern ridging pattern of summer 2010-2012.

Here at PHL, 1981-82 to 1984-85 was actually a good stretch. January 1982, 1984, and 1985 all had below zero cold shots and above average snow. (1/19/1994 was the only time in the almost 40 years since that we got a cold shot as bad as January 82, 84, 85.) Also, 82 and 83 had April snowstorms, and 84 had a cold and snowy March.

1992-93 and 1993-94 were good seasons as well. 1993 had the famous blizzard in mid-March and 1994 had a cold wave in January as well as above average snow in February.

Regarding the 2009-10 snow season, I know there was a strong el nino and that likely contributed to record snow in the Mid-Atlantic, but why did the snow come to an abrupt end in places like Washington DC and Baltimore after the February 9-10 snowstorm?

The crazy part about that 50 inches of snow in February 2010 is that almost all of it took place during the first 10 days of the month, with a tenth of an inch of snow on the 15th, and then the snow just suddenly stopped for the season. At that point in the season, Baltimore had more snow than Syracuse (and any other city) in the Golden Snow Globe contest in 2009-10: https://goldensnowglobe.com/baltimore-storms-past-syracuse-for-the-lead/ https://goldensnowglobe.com/stwc-vol-2-update/ Baltimore was passed by Syracuse on Valentine's Day and never looked back: https://goldensnowglobe.com/stwc-vol-2-outcome/ 50 inches of snow in 10 days and 80 inches of snow is something that will almost likely never happen again in Baltimore.

Even 2020-21 and 2021-22 were one month winters (February 2021 and January 2022) that were hit and miss here in the Philly viewing area. The early February 2021 snowstorm was a blockbuster to the north and west (not so much in the south and east), while the late January 2022 snowstorm was a blockbuster to the south and east (not so much north and west). PHL topped out at about 7.5 inches on both storms. There hasn't been a true blockbuster storm for the whole Philly viewing area since January 2016.

I highly doubt we're going to have a JFM colder than 2015 any time soon. Didn't JFM 2015 set a record for the coldest JFM in the Eastern US?

I think it was more of a case where the pattern formed way too late in the season for anything to really happen. Had that pattern formed in late December 2022 instead, we would have gotten a very cold February and March 2023, as seen by the blocking pattern we got in June 2023. That late April rainstorm would have been a big blizzard in early February, followed by a dry cold pattern most of February and the first half of March, and exited that with another snowstorm near the spring equinox. (Remember the record cold highs around the summer solstice last year. Now imagine how cold that would have been if that was late March instead.)

2016-17 wasn't enso neutral. It was a weak la nina. We had the 5 trimonthlys of -0.5 on the NOAA ONI, and got down to -0.7 on both the Eric Webb Ensemble and NOAA ONI. We even got down to -1.09 on the RONI. 2014-15 has a better argument for enso neutral than 2016-17. That one had the same strength as 2016-17 on the ONI, and only 0.58 on the RONI. So, the only ones that can be considered enso neutral are 2001-02, 2003-04, 2012-13, 2013-14, and maybe 2019-20 (an ENSO neutral on the RONI, but you could argue a continuation of a weak el nino on the ONI that began in 2018).

It was just too late in the season. However, we did get a nice blocking pattern in June (who could forget about the smoke out). June 2023 was the coldest June since 1985. Would have been nice if we had -NAO and -EPO in late December or even early February.

I know 2024-25 is not likely going to be an ENSO neutral season (we haven't really had a true one since 2013-14), but I've noticed that since 1950, we've pretty much come out of every ENSO neutral phase with an el nino, and never a la nina. (If you don't count 2019-20 as an ENSO neutral season, in which a stubborn weak el nino refused to dissipate, then the last time we exited an ENSO neutral phase with a la nina was in 1949.) Is there a reason why ENSO neutral phases generally lead to el ninos, or is this just a coincidence?

I'm not sure if it's a shift to summer because the Northeast Pacific blocking pattern was there in the summers of 2014 and 2015, maybe even late summer 2013. The onset was about the same for both seasons (2013 or 2014), it's just that the pattern never seems to be in place in the winter after 2015. The most amazing thing about this 10+ year Northeast Pacific summer blocking pattern is that the only summers here in the Eastern US that were below average were 2014 and 2023. Oddly enough, both of those years were pre-nino summers. 2016 and 2020, the post-nino summers, were well above average (only trailing 2022). Those three summers were among the warmest ever in many places in the Eastern US. As for 2019-20, that was one of the weirdest years ever. There was a stubborn weak el nino that just refused to dissipate. It didn't until fully until the spring.

That RONI plot is just a combination of the 2010-11 and 1998-99 peaks. I used the 2010 analog through OND, and then changed to 1998-99 starting with NDJ. I'm not so sure we even hit the 2010-11 peak of -1.7 now that we've fallen behind the pace. The ONI is just 1988 shifted 3 months until OND, then change to 1998-99 starting with NDJ.