PhiEaglesfan712

2002 was a very warm summer, but the 02-03 event was a moderate, as it didn't quite peak at above 1.5 on the ONI/RONI. 2009 wasn't warm, and in fact, one of the coldest June/July. 2015 was slightly warmer than normal, but 2016 was much warmer. 2014 was the cool summer, and you could technically count that as the pre-nino summer if you consider 14-15 (borderline warm neutral/weak el nino) as part of the el nino event. Almost all 1.5+ peak seasons have warmer post-nino summers than pre-nino summers, with the exception of the Pinatubo case in 91-92.

Yeah, it had to have either been 96 or 97. Both were really cool summers (followed 3 very hot summers). JJA averages (PHL) 1993: 78.2 1994: 78.4 1995: 78.6 1996: 74.0 1997: 74.2

Summer 2023 was a delayed summer. It was one of those rare ones where September was warmer than June. While JJA fell a tenth or two below the 1981-2010 average, the JAS temperature finished a tenth or two above the 1981-2010 JJA average. Plus, the early September heatwave helped drive up the 90-degree numbers for 2023. Also, I'm not sure where the narrative of record rainfall and flooding events going into the summer of 2023 came from, but aside from the April 28-30 rainstorm, that spring was pretty much dry here, with May 2023 being a record dry May. It really didn't get wet until about mid-June.

General rule is that pre-strong nino summers are colder and post-strong nino summers are warmer in the East. It wasn't 1995 (that was one of the warmest summers on record, as was 1993 and 1994). However, both 1996 and 1997 were cooler summers (1997 was a pre-nino summer). It must have been one of those years. The only time the rule didn't hold was when the pre-nino summer of 1991 was very warm, and the post-nino summer of 1992 was cool. However, we had a major volcano in 1991 (in Pinatubo), and that screwed things up. 91-92 behaved more like the reverse of the way a strong el nino would normally. Global temperatures actually cooled, as the effects of Pinatubo canceled out a robust el nino. Pre-strong nino/post-strong nino summer average temps (PHL) since 1970 72-73: pre-nino summer 72 (73.9); post-nino summer 73 (77.1) 82-83: pre-nino summer 82 (73.0); post-nino summer 83 (75.7) 86-88: pre-nino summer 86 (75.3); post-nino summer 88 (77.1) [summer 87 during the el nino was 76.5] 91-92: pre-nino summer 91 (77.9); post-nino summer 92 (74.0) 97-98: pre-nino summer 97 (74.2); post-nino summer 98 (75.7) 09-10: pre-nino summer 09 (75.1); post-nino summer 10 (79.6) 15-16: pre-nino summer 15 (77.7); post-nino summer 16 (78.8) 23-24: pre-nino summer 23 (75.8; although JAS was 76.1); post-nino summer 24 (78.5)

The difference is that we had record warmth in 2023 starting in January. I mean, we had to regress to the mean at some point. We had more blocking in late April, and that pattern lasted through May and June, and gave us our coldest May/June in many years. I don't expect that this year. It's likely May will be a lot closer to normal, but we aren't getting -2/-3 monthly temperature departures like May and June 2023.

What helped was a major volcano (Pinatubo). This caused global temperatures to drop temporarily, making it favorable for cold and snowy winters in 92-93, 93-94, and even 95-96. If not for that, then global temperatures would have broken records in 1992, following a 3rd robust el nino in a decade (after 1982-83 and 1986-88). But the cooling period was over by the 1997-98 super el nino, the fourth robust el nino in just over 15 years. Unless there is another Pinatubo this summer, I expect global temperatures to shatter another record (following a 2nd robust el nino in 4 years), making it unlikely we have another cold and snowy period like 92-93, 93-94, and 95-96.

Weeklies, by the way:

There's only been one: 1916-17 (and this was part of a triple la nina, which began in 1915-16 and ended in 1917-18). That was when global temperatures were at a minimum in the post-Industrial Revolution era. Of course, 1916-17 and 1917-18 are some of the coldest CONUS winters on record, and I believe the super la nina had a hand in it. The closest we've come since then were in 1973-74 and 1988-89, and both immediately followed robust el ninos (the super el nino of 1972-73 and double el nino of 1986-88, respectively). Classic cases of "sometimes the strongest el ninos are followed by the strongest la ninas". I feel like if we get a strong/super el nino, this time around it's going to be followed by a strong la nina, like in 1973, 1988, 1998, and 2010.

April 1976 was well above average in most of New England, and above average in New York, eastern PA, and NJ. This is still Boston's warmest April on record. Although, April 2010's warmth is much more widespread for the Eastern US.

Yeah, 50 years ago was the Easter/Patriot weekend heatwave:

May and June that year was really cold. I don't think it reached 96 in those months (I know it did in July and September). Of course, there was the freeze on May 18.

Who knows, maybe we'll get a nice rainstorm/mud season in October this time, when the high school football season is in full swing.

Same thing with the strong la ninas. 1916-17 was the only one in the first 100+ years post-1850. (Coincidentally, 1917 was the year when global average temperature hit a minimum.) Since then, we've had strong la ninas in 1955-56, 1973-74, 1975-76, 1988-89, 1998-2000, 2007-08, and 2010-11.

Eric Webb's list has 1877-78, 1888-89, 1972-73, 1982-83, 1997-98, and 2015-16 listed as super el ninos. Those are the only years when both the ONI and RONI were above +2C.

Also, May 9, 2020. Both of those happened after very warm and virtually snowless winters.

That leaves us with 1972 and 1982 from the super group. (You already did 1997.) From the strong group, we have 1957, 1965, 1986, 2009, and 2023. 1987 (el nino already in progress, 1986 would be the year to use as I mentioned above) and 1991 (another high end warm neutral like 2015, plus had a major volcano) probably aren't good comparisons.

Yeah, 2015 was one that took several years to form. People were predicting el nino as early as 2012. Definitely by 2014, you just knew a super el nino was going to form when the ingredients came together. It didn't again in 2014, but in 2015 it did, after 3-4 years. It's no surprise the 2015-16 event was one of the strongest el ninos on record. All I know is that a super el nino is going to form at some point in the near future. It may not be this year, and even if the trades come back later this spring, it may just be delaying the inevitable until the following year.

Don't you mean April? And I think these temperatures are severely underestimated. This April looks like it's going to be near record warm.

It's amazing how quickly a pattern can change. Not even 6 weeks earlier, we were wrapping up a very cold and snowy February. Almost like what we have this year.

This can't be. Pinger season has been done for 2 months now.

1.5, even if not strong, is still notable. In the last 77 years, we've only had 10 events that cleared 1.5 on both the ONI and RONI (only 4 of these, in bold, cleared 2.0 on both - the threshold for super): 1957-58 1965-66 1972-73 1982-83 1986-88 (this was a double year el nino, which unlike the others, peaked in the summer of 1987) 1991-92 1997-98 2009-10 2015-16 2023-24

That April 1982 snowstorm showed just what could have been. If not for a long lull in February and March, 1981-82 could have been a historic snow season. But the April storm was a nice reminder of that cold and snowy pattern in January 1982.

Global temperatures seem to bottom out around 1917 (following a super la nina), at about -0.2 lower than the 1850-1900 pre-industrial mean. If we use 1917 as the zero point, 1.5C would have been first breached in 2016, and the global temperature anomaly for 2024 would be at +1.8C.

I believe it was 1997. I remember Easter Sunday, March 30, being warm. Then, it snowed on Monday (3/31) and Tuesday (4/1). 1997-03-30 68 54 61.0 12.8 4 0 T 0.0 0 1997-03-31 58 31 44.5 -4.1 20 0 0.66 2.3 0 1997-04-01 52 33 42.5 -6.5 22 0 0.06 1.6 3