PhiEaglesfan712

Yeah, it looks like January was the outlier month. At PHL, December and February had 18 in of snow, with March 6 in. Also, the cold continued into the spring, as May 1967 was the coldest May on record by a full degree F.

My guess is that the high school football season for Philly started this past weekend, so the schools have to be session.

Composites if we have an east-based la nina in 2024-25:

I have a feeling the la nina is going to take a 2021-22 trajectory. The la nina is going to be weak most of the fall/winter, but turns moderate in the spring, and maybe even strong in the summer (and holds on through the 2025-26 season). The only thing I don't know is if the la nina takes an east-based turn. If it does, then this upcoming winter should resemble 2021-22.

For the east coast to cash in, I think east-based la nina setup is the best scenario. ACY really outperformed in years like 2017-18 and 2021-22. I think a central-based la nina is going to favor west of PHL/I-95 like 2020-21.

lol, we're not coming anywhere close to 200 ACE. The fact that we're in a lull (again) in what is supposed to be the heart of hurricane season should make it pretty apparent. I think we're going to have a near normal number of named storms a la 1998/2007/2016. The only thing in question is whether the ACE total is going to be closer to the high end (1998) or low end (2007), or in the middle (2016). The fact that the 3 seasons (which are fairly similar imho) vary wildly in ACE shows its limitations, and why I don't put a lot of stock into that measure. I use the named storms/hurricanes/major hurricanes as benchmarks/measuring sticks. So far this season, we've been on the low end on those measures at all points in the season compared to the last 10 years. And unlike this season, 1998, 2007, and 2016 all had activity in the heart of the season. 14 or 15 seems like the right number of storms we are going to finish with this year, and I wouldn't be surprised if it is less. But no way are we going past 17, and the ACE won't pass the 1998 number. It will end somewhere around the 2016 number, maybe less.

Didn't the Southeast Ridge finally break around mid-April 2023? If I remember correctly, places as south as Georgia got frost/freeze as late as May 18, which hurt the peaches crop that year. Regarding 2020-21 and 2021-22, I believe that perhaps the biggest difference is that the former was a central based la nina, while the latter was an east based one. I think east based la ninas favor the eastern (coastal) areas. ACY had more snow in 2017-18 and 2021-22 (years that were east based la ninas), and didn't do as well as in the central-based 2020-21.

The difference was the pattern favorable for cold was in place by November in 2017-18. This winter has been talked about ad nauseum in this forum. December and the first half of January had major cold, and I think there was a major snowstorm in early January, which especially impacted Atlantic City. (Actually, the first taste of major cold was on November 10.) February was the real outlier. March had 3-4 snowstorms here in the mid-Atlantic and the cold continued well into April, but it helped that the cold was there earlier in the season. We didn't really have any of that in 2023. I wish the pattern was in place earlier. This map of May-August shows the potential that could have been there (if the blocking pattern was in November, imagine this in January-April instead - and much of the cold was in the first 2 months, which would have been January and February):

That is still too late for anything substantial to happen. If we were going to get a backloaded winter, January or early February at the latest is when the change needed to happen. A change in March is going to affect the spring into early summer, and that is exactly what happened. The cold finally came the last week of April, and didn't relent until late June. But the summer was clearly tipping its hand at being on the cool end with that change in March and the transition to el nino. It was the coldest June since 1985 and summer (JJA) since 2009.

The reason why it didn't work in 2023 is because the blocking pattern came way too late. It usually takes at least a month or two to see the full effects of it. Had the blocking been in place in November or December, then the full effects of the pattern would have happened in the heart of winter, and there would have been big snow and cold. As it was, we saw the full effects of the blocking in May and June, and of course, that was way too late for snow.

But why was 1995 a hyperactive season, while a similar year, 1983, which was also a developing la nina in +PDO, produced the least active season in the satellite era? And it's not like the following year, 1984 (another +PDO la nina), was that active either. What's interesting is that outside of 1980 and maybe 1981, the rest of the 1980s were filled with a lot of inactive seasons. I get 1982, 1986, and 1987 because of strong el nino years, but even some of the la ninas produced some underwhelming seasons.

I feel that an active season is more likely if after the 2nd year of a la nina, we get a neutral, rather than a 3rd year la nina. None of the 3rd year la nina seasons (1956, 1975, 2000, or 2022) were particularly active. Meanwhile, 2012 (a neutral season) was just as active as 2010 and 2011. First year la ninas are either hit or miss. Years like 2005 and 2020 were hyperactive and 2010 active, but years like 1970, 1973, 1988, and 2007 were not really big seasons. Second year la ninas seem to be the sweet spot, like 1999, 2008, 2011, and 2021. Next year, assuming the la nina continues (which is a high chance given the -PDO), is probably going to be the active season.

Maybe we could carve out a 1998-99 type season. That was a very warm first 3 weeks of December. We got most of our snow from Dec 23 to mid-January. We got no snow and it was warm until the 3rd week of March, which produced one more snow event.

If we go by the MEI, which has 2023-24 as a weak el nino, then 2007-08 is the closest match. Next best would be 2020-21. I guess our best hope is the la nina goes east-based. Then maybe we could squeeze out a 2021-22 or even 2017-18 type winter.

Euro hinting at a cooler beginning, but a warm end, to September:

My top analog years: 1998: 4 named storms by Aug. 30 (14 total named storms) 2007: 5 named storms by Aug. 30 (15 total named storms)

The cold winters of 2014 and 2015: The rest of 2015 was warm, especially May, November, and December:

If we're talking about 2013-14, then that one tipped its hand in July with the ridge building in the PNW. I mean, we got a big flip in the temperature pattern midway through the summer. The change in PDO pretty much sealed the deal. If we're talking about 2014-15, well that was just a continuation of the +PDO/PNW ridge. JFM 2014 and 2015 were the coldest this side of 1980. Even the summer of 2014 was cooler than average (the coldest since 2010, though some places were cooler last summer). The PNW ridge finally subsided in spring 2015 (which is why we got a very warm May here, and a cold May in most of the West).

13-14 and 14-15 were more straightforward to me than 17-18. In 17-18, the record warm October threw me off. That one and a record warm February really skewed things.

2021-22 analog if 2024-25 turns to an east-based la nina: As you can see, the classic one cold month and the rest warm in the Eastern US.

For 13-14, the pattern changed long before Sept/Oct. I think it changed some time in mid-July. I've never seen a summer all of a sudden turn from hot to cold in the middle like that one. But that was a very wet summer from start to finish. Of course, that was a sign of things to come.

Didn't Felix (Cat 5) also develop in that window? I believe it was Aug 31.

Don't worry, 2022 is very low on my list. I have years like 1998 and 2007 very high up (and you can possibly talk me into 2016). Not the best for winter weather in the mid-Atlantic, but could be very good for the Midwest and New England. What we have here is a developing first year la nina with a very cold subsurface. 1998, 2007, and 2016 all have those characteristics. We don't have that in 2022. That was a dissipating la nina, which peaked moderate early in the season (and in fact, you could argue was a carry over from the previous season). [I mean, in hindsight, it was easy to see coming with the very warm subsurface in summer 2022.] Now, here's the wrinkle: If the la nina peaks late into the season and turns more east based, then 2021-22 is going to look like a very good analog in hindsight. (I can see the late peak and carry over into 2025-26, but don't see an east based la nina right now.)

FWIW, the August 2024 CPC and IRI forecasts look eerily similar to August 2021: What ended up happening is a moderate la nina, which peaked very late into the year, and you could make the argument that it carried over to the next year. I've been hinting at a possible between season peak for this la nina. I wouldn't be surprised if 2024-25 and 2025-26 repeated the same ONI trajectory as 2021-22 and 2022-23.

The thing about the 2023-24 el nino is that the RONI peaked at about +1.5, which is in line with the 2009-10 el nino, a borderline moderate/strong el nino. Here's the crazy part, though: The MEI had 2023-24 only as a weak el nino, with a peak similar to the 2006-07 el nino. I'd put 2023-24 in line with years like 57-58, 65-66, 91-92, and 2009-10 (as well as 86-88, but that was a summer peaking el nino). All strong el ninos, but not super el ninos. The 2009-10 and 2023-24 el ninos fall short on the MEI compared to 86-88 and 91-92 el ninos. And you won't believe this, but the ENSO neutral years following the 91-92 el ninos (92-93 and 93-94) even had a higher peak on the MEI than 2009-10 and 2023-24. [Note: If you include the natural el nino in 94-95, then you basically have a 4-year strong el nino on the MEI.]