2024 Indicators: SST's, MSLP, Shear, SAL, Steering, Instability (Day 16+ Climate Models)

[toad strangler]

I stand corrected, three hurricanes and 2 majors made direct landfall in 2004 fully geographically based (even if the bulk of Ivan's damage was over Florida). Definitely a historic season, and hopefully not one 2024 is trying to out do 20 years later.

Frances was a slow moving brute of a Cat 2. It took very long to move out and that made impacts much sharper than one would expect. PLUS Frances was a COMPLETE hurricane with a LARGE front and back end. Unlike many of the "halfacanes" we have been seeing recently.

[Patrick99]

I stand corrected, three hurricanes and 2 majors made direct landfall in 2004 fully geographically based (even if the bulk of Ivan's damage was over Florida). Definitely a historic season, and hopefully not one 2024 is trying to out do 20 years later.

Frances was a slow moving brute of a Cat 2. It took very long to move out and that made impacts much sharper than one would expect. PLUS Frances was a COMPLETE hurricane with a LARGE front and back end. Unlike many of the "halfacanes" we have been seeing recently.

Yeah, and Jeanne didn't exactly cheat anyone out of the whole hurricane experience, either.

[aspen]

As of today, 2024 has the second highest ACE-per-storm of any season during this current active stretch (2016-onwards). It’s second only to 2017, and just ahead of 2016, which was also a backloaded first-year La Niña season.

2024: 9.69 ACE/storm (145.30 ACE, 15 NS)
2023: 7.28 ACE/storm (145.56 ACE, 20 NS)
2022: 6.74 ACE/storm (94.42 ACE, 14 NS)
2021: 6.93 ACE/storm (145.56 ACE, 21 NS)
2020: 6.01 ACE/storm (180.37 ACE, 30 NS)
2019: 7.34 ACE/storm (132.20 ACE, 18 NS)
2018: 8.84 ACE/storm (132.58 ACE, 15 NS)
2017: 13.23 ACE/storm (224.88 ACE, 17 NS)
2016: 9.42 ACE/storm (141.25 ACE, 15 NS)

Another thing worth noting is how extremely close 2021 and 2023 were in terms of seasonal numbers, despite wildly different ENSO states. A very unusual coincidence.

[toad strangler]

I do believe there is a good chance to reach the hyperactive threshold with the forecasted convective pulse forecasted to move into the basin in about a week.

[Hurricane2022]

Frances was a Cat 2 when landfall occurred in Martin County, FL.

Awesome analysis as usual. Slight appendage to this though, as 2004 had four major hurricanes strike Florida (Charley, Frances, Ivan, and Jeanne):
https://i.imgur.com/EzBDJj1.png
https://i.imgur.com/x0dvbPU.png

This tied 1886 with the most hurricane strikes in on year (four in Texas):
https://i.imgur.com/7CoKs76.png
https://i.imgur.com/wp2Ahyc.png

Thanks for the additional information. In the 2004 image you posted, hurricane Ivan made landfall in Gulf Shores, Alabama instead of Florida. I know it's a bit silly since we're talking about a distance of about 20 miles to the Florida border so in terms of Florida impacts it doesn't really change anything. But I used a hard filter for the Florida border so even hurricanes 1 mile west of the border wouldn't count. That's the reason my overview has 3 hurricanes for 2004. And Frances was a cat 2 when it made landfall in Florida, thus leaving 3 hurricane landfalls in 2004 of which 2 were major hurricanes. But these details aside, 2004 was indeed a crazy year.

I stand corrected, three hurricanes and 2 majors made direct landfall in 2004 fully geographically based (even if the bulk of Ivan's damage was over Florida). Definitely a historic season, and hopefully not one 2024 is trying to out do 20 years later.

In fact 2024 has been FAR worse than 2004 so far. Wikipedia says this season is now SECOND Costliest cyclone season ever recorded, surpassing 2005 and 2022 and now only behind 2017. That's mostly due to Helene and Milton, of course.

[weeniepatrol]

CPC from back on 22 October:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/ghaz/index.php

The Madden-Julian Oscillation (MJO) completed a circumnavigation of the global tropics by mid-October with its enhanced phase currently over the Maritime Continent. During the past week, the MJO strengthened based on the RMM index and the 200-hPa velocity potential anomalies. Recently, the anomalous upper-level divergence (convergence) increased over the Maritime Continent (Americas and Africa). Despite destructive interference between the MJO and the emerging weak La Nina during the next week, the GFS and ECMWF models are in good agreement and consistent that a moderate to strong MJO propagates eastward to the western Hemisphere. By early November, the MJO is predicted to shift east from the Americas to Africa and the Indian Ocean.

A pair of tropical cyclones (Nadine and Oscar) formed over the Atlantic basin this past week. Nadine was a short-lived TC and Oscar rapidly became a hurricane as it tracked north of Hispaniola. The GFS and ECMWF ensemble members support a 40 to 60 percent chance of TC development across the Caribbean Sea from October 30 to November 5. Many of these ensemble members depict TC genesis occurring as early as October 29. Regardless of the exact timing, forecast confidence is high that another TC forms across the Caribbean Sea by the end of October. Model guidance is also depicting an elevated chance of a subtropical low pressure system or tropical cyclone forming at a higher latitude over the southwestern Atlantic. This would be consistent with climatology and thus a 20 to 40 percent chance is posted for this region during week-2. From November 6 to 12, a 20 to 40 percent chance of TC development is posed for the Caribbean Sea based on climatology and since the MJO is likely to maintain a favorable large-scale environment for a late season TC through at least mid-November.

This is quite a bullish discussion, due to extended-range global ensemble support, near-record warm SSTs, a moderate-to-strong amplitude MJO propagating into the most favorable Atlantic phase (providing broad large-scale support and anomalous rising air), and La Nina climatology favoring late-season Caribbean development. Would not be surprised to see enough activity to nudge the season above the 159.6 ACE hyperactive threshold.

[weeniepatrol]

Welcome to the last day of August October

[Pasmorade]

When are Australia and the rest of the South Pacific most likely to get their first tropical cyclone of the season. Asking as the climatological start to both seasons is tomorrow.

[cycloneye]

 https://x.com/philklotzbach/status/1852683386801848815

[WaveBreaking]

This is not a TWO map I’d expect to see in November

[WaveBreaking]

The Atlantic has seemingly returned to a classic +AMO horseshoe after the large cold pool near the Iberian Peninsula/African Coast and the infamous warm blob near Newfoundland during the peak season dead period.

[tolakram]

This season can't do anything except disappoint.

In my opinion, and this is a strong one. Counting storms is NOT objective, it's subjective. If we have 8 cat 5 hurricanes this season and that's all, was it slow? It's just silly and can do nothing except hurt the institutions that live or die by the numbers.

If this season ends up unusually inactive, and I'm not predicting that, maybe some improvements will result. Since we've already had a cat 5 in July, if this season ends up being unusually inactive what will that tell us?

And I think it was in this thread, hopefully quoted, that there's no spring barrier this year.

Honestly I think cold neutral is far worse (more activity) than a full la nina anyway.

It's still not hyper, but so far what a crazy season. I think my point is still valid, big storms causing a lot of grief is more important than the count, but disappointed? NO.

We're still in the 70's up here, stuck in some early fall pattern. I can't find any relationship between this and hurricane season, but I would not be surprised at this point to see some very late activity.

[chaser1]

This season can't do anything except disappoint.

In my opinion, and this is a strong one. Counting storms is NOT objective, it's subjective. If we have 8 cat 5 hurricanes this season and that's all, was it slow? It's just silly and can do nothing except hurt the institutions that live or die by the numbers.

If this season ends up unusually inactive, and I'm not predicting that, maybe some improvements will result. Since we've already had a cat 5 in July, if this season ends up being unusually inactive what will that tell us?

And I think it was in this thread, hopefully quoted, that there's no spring barrier this year.

Honestly I think cold neutral is far worse (more activity) than a full la nina anyway.

It's still not hyper, but so far what a crazy season. I think my point is still valid, big storms causing a lot of grief is more important than the count, but disappointed? NO.

We're still in the 70's up here, stuck in some early fall pattern. I can't find any relationship between this and hurricane season, but I would not be surprised at this point to see some very late activity.

All in all, there's no way to avoid the fact that SO many (11 I believe?) named T.S. or hurricanes made landfall within the Atlantic basin thus far. Thats a lot of people affected and a tremendous amount of damage and suffering. ACE and number of storms are just two ways that the public can view how active any season is/was but there's no escaping that the greatest actual impact are the direct affects to people and property.

[Category5Kaiju]

I guess this season really validated Klotzbach's hyperactivity sst-composite map. It took until late September to really crank things up, but in the end the insanely warm deep tropical waters allowed this season to brute force its way to hyperactivity, not matter how unusually unfavorable conditions were during late August and early September.

Probably a good lesson for predicting future seasons: if -ENSO is present and Atlantic tropics are very warm, chances are rather likely you'll get a very active season.

[WalterWhite]

I guess this season really validated Klotzbach's hyperactivity sst-composite map. It took until late September to really crank things up, but in the end the insanely warm deep tropical waters allowed this season to brute force its way to hyperactivity, not matter how unusually unfavorable conditions were during late August and early September.

Probably a good lesson for predicting future seasons: if -ENSO is present and Atlantic tropics are very warm, chances are rather likely you'll get a very active season.

Not really. In this +AMO regime (2016 onwards), above-average activity is essentially a given for almost any hurricane season. (2022 was a huge anomaly in this respect, likely due to the fact that it was a third year La Niña). If above-average activity is essentially going to be a given in this +AMO period, it becomes more useful to distinguish seasons that are slightly above-average (such as 2016, 2018, 2019, 2021, and 2023) from seasons that are hyperactive (such as 2017, 2020, and as of today 2024).

The fact that we have a season with a record-warm Atlantic and a negative ENSO (theoretically the perfect base state for a hurricane season) only barely manage to break the hyperactivity ACE threshold and not fail to exhaust the main naming list means we do not know as much about hurricane seasons as we think we do.

[Category5Kaiju]

I guess this season really validated Klotzbach's hyperactivity sst-composite map. It took until late September to really crank things up, but in the end the insanely warm deep tropical waters allowed this season to brute force its way to hyperactivity, not matter how unusually unfavorable conditions were during late August and early September.

Probably a good lesson for predicting future seasons: if -ENSO is present and Atlantic tropics are very warm, chances are rather likely you'll get a very active season.

Not really. In this +AMO regime (2016 onwards), above-average activity is essentially a given for almost any hurricane season. (2022 was a huge anomaly in this respect, likely due to the fact that it was a third year La Niña). If above-average activity is essentially going to be a given in this +AMO period, it becomes more useful to distinguish seasons that are slightly above-average (such as 2016, 2018, 2019, 2021, and 2023) from seasons that are hyperactive (such as 2017, 2020, and as of today 2024).

The fact that we have a season with a record-warm Atlantic and a negative ENSO (theoretically the perfect base state for a hurricane season) only barely manage to break the hyperactivity ACE threshold and not fail to exhaust the main naming list means we do not know as much about hurricane seasons as we think we do.

"We do not know as much about hurricane seasons as we think we do"

Precisely. The late August/early September shutdown was due to several factors that couldn't really be predicted well in advance, and the exact nature of a given hurricane season will never be known in advance due to intraseasonal factors. With that, this season underperformed compared to the 200+ ACE predictions and the 20+ NS predictions earlier this summer.

However, the idea that the warm deep tropical waters and the -ENSO setting in after a strong El Nino gave credence to the idea that this season, regardless, had a strong chance of ending as a hyperactive season, had a strong chance of featuring at least 5 major hurricanes (with the possibility of a sub-900 mbar storm), and had a strong chance of being backloaded with activity extending into November. I've seen many make those generic predictions earlier this season, and now that we're in the home stretch it does look like those are coming to fruition.

The season is at 160 ACE, with the possible future Caribbean system that quite a few models seem to be sniffing out potentially growing into a powerful system. We've had 5 major hurricanes already, with Milton becoming our first sub-900 mbar system since 2005. And activity really did pick up since Francine formed in mid-September. We can only speculate how much more active this season would've been had the peak season shutdown not happened, but there's no denying that this has been one of the most destructive, active, and insane seasons in recent times.

[Steve]

^^ all that with bad m(o)jo during the peak. All I can say is that mid level remnants of Rafael are raining down on Pensacola at the moment. CFS, bias corrected EC and bias corrected Australian say phase 3 in 10-12 days. We should have another system or two.

[Category5Kaiju]

You know, with the theory that the conditions we're seeing are more typical of the month prior, I'm genuinely beginning to wonder if this season will feature storms in December. Would really be something if we manage to get a hurricane, let alone a major hurricane, during that month. Normally, I don't really think about such a crazy happening, but with how this season has behaved, I'm not going to discount anything until it seems for sure that the season is indeed over.

[AnnularCane]

You know, with the theory that the conditions we're seeing are more typical of the month prior, I'm genuinely beginning to wonder if this season will feature storms in December. Would really be something if we manage to get a hurricane, let alone a major hurricane, during that month. Normally, I don't really think about such a crazy happening, but with how this season has behaved, I'm not going to discount anything until it seems for sure that the season is indeed over.

I was just thinking of that possibility too, although not thinking a December major at this point. But who knows, maybe we could get a storm or two.

[cycloneye]

Made a poll about December