PhiEaglesfan712

2024-25 la nina RONI -1.2 to -1.4 MEI -1.5 to -1.7

Everything is opposite to what we have this year. That was a +PDO and -AMO year. 2007-08 and 2020-21, despite both being at a solar min, seem like the best matches to me. I'd give 07-08 the edge as the top analog because the hurricane activity of 2007 is even very similar to this year. 1998-99 and 2016-17 are other good matches.

Next year, we might be, though. Right now, we are still in the deep negative PDO phase like 2011 and 2012: 2011 -1.80 -1.46 -1.28 -1.02 -0.66 -1.08 -2.30 -2.37 -2.50 -1.92 -2.95 -2.40 2012 -1.85 -1.35 -1.66 -1.01 -2.12 -1.63 -2.40 -2.60 -2.99 -1.22 -0.66 -1.31

What happened with the PDO in 2013 is what I see happening in 2025. We will start to moderate out and be in the -0.5 and -1.5 range. 2013 (2025) -1.10 -1.42 -1.48 -0.72 -0.40 -1.19 -1.34 -1.56 -1.00 -1.65 -1.09 -1.04 This will set the stage for a +PDO el nino in the 2026-28 timeframe. 2014 (2026) -0.57 -0.42 0.30 0.36 1.27 -0.28 0.25 0.34 0.76 1.43 1.35 1.86 2015 (2027) 1.51 1.52 1.33 0.90 0.32 0.82 1.41 0.98 0.97 0.84 0.17 0.29 2016 (2028) 0.75 1.29 1.56 1.74 1.60 0.87 0.57 -0.63 -0.80 -0.43 0.96 0.61

It's crazy to see how disjointed the ONI, RONI, and MEI are right now. As recently as 2020-21, the 3 indices were in tandem. I wonder if the indices are going to start converging this year and all peak in the -1 to 1.2 or -1.2 to -1.4 moderate la nina range, or if we're going to get a year where the ONI that's barely a weak la nina or even a cold neutral, while the RONI is a moderate la nina, and the MEI is a strong la nina.

If I had to venture a guess on this winter, my gut feeling tells me it will be somewhere between 2007-08 and 2020-21. Those years are the best match on the RONI/MEI. I think we get a snow event in the first half of December, then a lull in snow until the end of January, and February will be the snowiest month, with the snow season coming to an abrupt end around February 22nd.

If I had to bet, in 12 months we'll probably still be in la nina, but the subsurface will turn warm (like 2021 and 2022). I also think the PDO will still be negative, but not in the -2's or -3's, rather in the -1's and making its way towards 0. The signs of a future el nino will be there, with the only thing left to see is if it develops in 2026-27 or 2027-28.

Quite frankly, I don't know because it's a fluky event that has no precedence. It would be like if it snowed in Orlando during the vernal equinox, and asking if it's a good signal for Melbourne during the Austral winter. It hasn't happened before, so I couldn't tell you one way or the other. I mean, we got a fluke snow event in late October 2011, and that winter ended up as one of the warmest and least snowy on record.

That would be like if it snowed in Orlando on March 19.

What would make my winter is if we got a snowstorm on Super Bowl Sunday (February 9, 2025) like we did during the winter of 20-21.

What was similar was the strong -PDO. However, 1949-50 was the last la nina to form from a true ENSO neutral season, rather than from an el nino (unless you count 2019-20 as an ENSO neutral season rather than a disjointed el nino that started in late 2018, then it's 2020-21). 1949-50 was a late-blooming moderate la nina, and 1950-51 was a weak la nina that piggy backed off it. Both were among the least snowiest winters at PHL. January 1950 was one of the warmest on record here, but that was followed by a long string of negative temperature departure months.

I'll take 2008-09 any day over 2022-23. I just wish the cold and snow would have aligned. At least in 08-09, we got a cold October-January, and the big snowstorms in early February and March 1-2. I think we also got a snow event in mid-November.

I don't think there was a -PDO/strong el nino combo in the past 75 years. The closest ones were 1965-66, 1972-73, and 2009-10, and all were close enough 0 PDO during the el nino event (although 1972-73 and 2009-10 were surrounded by multi-year la ninas, and were deeper -PDOs outside of the el nino event). 1965 -0.95 -0.61 -0.17 -0.01 -0.66 -0.76 -0.74 0.32 0.83 0.30 0.47 0.25 1966 -0.67 -0.43 -1.00 -0.37 -0.76 0.10 0.01 -0.29 -0.35 -0.60 -0.71 -0.21 1972 -2.12 -1.95 -1.53 -1.70 -2.16 -1.84 -1.48 -0.11 -0.20 -0.22 -0.05 -0.37 1973 -0.15 -0.55 -0.88 -1.35 -1.59 -1.44 -1.40 -1.56 -1.05 -1.36 -1.42 -0.89 2009 -1.81 -1.78 -2.06 -2.23 -1.32 -0.73 -0.71 -0.49 0.33 -0.13 -0.94 -0.51 2010 0.05 0.25 -0.16 -0.04 -0.18 -0.79 -1.99 -2.21 -2.45 -1.60 -1.57 -2.04 Those three years produced one that was bitter cold (1965-66), one that was snowless (1972-73), and one that was the snowiest winter of all-time (2009-10) here at PHL. 2023-24 was none of that, but rather one of the warmest winters at PHL. Proof that a strong el nino is more of a wild card more than anything.

First year la ninas that were misses 1970 (2nd year la nina 1971 was near average) 1973 (2nd year la nina 1974 was below average) 1983 (2nd year la nina 1984 was near average) 2007 (2nd year la nina 2008 was active)

1st year tend to be hit and miss. However, the ones that are a hit tend to be hyperactive (1995, 2005, and 2020). 3rd year la ninas (there are only 4: 1956, 1976, 2000, and 2022) have all been underwhelming. Sometimes, a neutral season after 2 la nina years can be more active (think 2012, which was the third straight above average season).

2nd year la ninas tend to have above average hurricane seasons in the Atlantic. 2008, 2011, and 2021 are especially very good examples.

If we're going to be stuck in deep negative PDO, I really can't see anything else but a continued la nina.

That's certainly possible. The thing with el ninos is that you can see them coming, but they can take years to develop. In the mid-2010s el nino, a lot of people were calling for it to happen in 2012-13, but didn't start to develop until 2014-15 and the super el nino happened in 2015-16. The next el nino could happen in 2026-27, or it could happen in 2027-28. Whenever it happens, I think the PDO will have flipped to positive. Ideally, the subsurface will turn warm either by next summer or the summer of 2026.

Considering the MEI is already at -0.7 (it's already achieved weak la nina status for 2024-25), I think the AS reading should be deep into moderate la nina territory, possibly even reach the strong la nina threshold.

I will always find it amazing how the Tuck Rule game happened during the only day it snowed on an otherwise record warm winter of 2001-02. This storm and the January 2016 blizzard are classic examples of one storm making an otherwise very warm winter season memorable.

The difference is the subsurface was warm in the 2 summers leading up to it. We still have a cold subsurface and the PDO is even deeper negative. I just cannot see how an el nino will form under those conditions. An el nino in 2025-26 would truly be an outlier. In the previous 75 years, no year with a deep negative PDO and cold subsurface produced an el nino the following year.

Yeah, the PDO still in deep negative. I think this means we can also rule out an el nino forming in 2025-26. If one was going to form, wouldn't the PDO be heading back towards positive? We're likely to get a 2nd year la nina, although there is a chance for an ENSO neutral.

I prefer a blend of 2007 and 2020 as my analogs. They are the best matches on the MEI. If I were to use 2022, I'd use it as a reverse log. Everything seems to be lining up opposite. 2022 was a dissipating la nina, a warm subsurface, and a record warm August/September. This year is a possibly strengthening la nina, a cold subsurface, and a relatively cool August/September. Who knows, maybe this time we get a cold January/February (and maybe a record warm May/June):

Give me +PNA/+NAO in November, and now we're talking.

If that's the case, then the MEI is going strong la nina in 2024-25. It would be the 3rd strong MEI la nina in 4 years. If the MEI is out of sync with the ONI and RONI in 2024-25, it would be the 4th straight season dating back to 2021-22. All had 2020-21 as a moderate la nina.