2024 Atlantic Hurricane Season

[Stormchaserchuck1]

Not to hype this season further because there are a lot of factors that involve tropical cyclones: African dust, etc, and for the longest time of several decades we did average in the Atlantic 9NS/year. But last year we did see 20 named storms in Strong El Nino. That blew out previous El Nino stats, for all El Nino's (Weak-Mod-Strong): 

	TS	Hurr	MH
1951	12	8	3
1953	14	7	3
1957	8	3	2
1963	10	7	3
1965	10	4	1
1968	9	5	0
1969	18	12	3
1972	7	3	0
1976	10	6	2
1977	6	5	1
1979	9	6	2
1982	6	2	1
1986	6	4	0
1987	7	3	1
1991	8	4	2
1994	7	3	0
1997	8	3	1
2002	12	4	2
2004	15	9	6
2006	10	5	2
2009	9	3	2
2014	8	6	2
2015	11	4	2
2018	15	8	2
2023	20	7	3

1953, 1969, 2004, and 2018 were all Weak El Nino's.  So the record for Moderate+ El Nino's before last year was 12 named storms (1948-2022). 

The warmer water temperatures, which were a leap above previous years, did play a role last year. 

[Stormchaserchuck1]

We also now have a pretty strong cold pool of water developing in Nino 3. These deep-pocket starts usually precede Moderate+ events.  

https://ibb.co/qspXSjq

[tiger_deF]

MDR is absolutely toasty right now, hard to imagine a more favorable look. I can't remember ever seeing this level of warm anomalies across the tropical Atlantic, and as the SATL and El Nino regions are cooling off, it continues to warm. OHC anomalies in the MDR are a month ahead of 2023 and 3 months ahead of the 2013-2022 average. 
 

[tiger_deF]

For pre-season development I have my eyes on a tropical wave which for several runs has been shown for several runs to move off of South America into the Caribbean in around 7-10 days. It will potentially move NE to the open Atlantic, as shown by this 018z GFS run, where it might be able to align along the shear vector at some point and develop. Waters are certainly warm enough

SAL and high wind shear from zonal continental flow is currently dominating the basin (typical in Mid-May), so the tropical Atlantic is going to be shut down asides from a potential sneaky system for some time. However, MJO is moving into the basin in late May, and as the ICTZ continues to tick northwards and pockets of lower shear start to pop up, things will start looking more favorable for some early-season development, and one of the most hyped seasons in years will truly begin.

[Windspeed]

MDR is absolutely toasty right now, hard to imagine a more favorable look. I can't remember ever seeing this level of warm anomalies across the tropical Atlantic, and as the SATL and El Nino regions are cooling off, it continues to warm. OHC anomalies in the MDR are a month ahead of 2023 and 3 months ahead of the 2013-2022 average. 
 

It's straight stupid how anomolous the current 28°C isotherm is across the MDR. I always pay more attention to that as it's really the harbringer of major hurricane potential. As soon as the upper atmosphere begins to settle into more of a late Summer / July pattern combined with La Niña and weakening trades, I fully expect an early onset of CV ASO+ and a hyperactive season.

[WxWatcher007]

8 hours ago, Windspeed said:

On 5/13/2024 at 11:45 PM, tiger_deF said:

MDR is absolutely toasty right now, hard to imagine a more favorable look. I can't remember ever seeing this level of warm anomalies across the tropical Atlantic, and as the SATL and El Nino regions are cooling off, it continues to warm. OHC anomalies in the MDR are a month ahead of 2023 and 3 months ahead of the 2013-2022 average. 
 

It's straight stupid how anomolous the current 28°C isotherm is across the MDR. I always pay more attention to that as it's really the harbringer of major hurricane potential. As soon as the upper atmosphere begins to settle into more of a late Summer / July pattern combined with La Niña and weakening trades, I fully expect an early onset of CV ASO+ and a hyperactive season.

Totally agree. 2024 has been in a class of its own so far. I also think the SSTA distribution makes it less likely for stability issues in the MDR? Seems like a good +AMO setup. What’s another year with the classic horseshoe distribution?

From Andy Hazelton:

29C for May 14 is just off the charts absurd.

[Stormchaserchuck1]

It may also take 10-15 more years for the Atlantic to cool down, if the AMO ever does switch phases. Right now it's positive and still strengthening, but history through the 1900s shows that it does have decadal trends. 

[Ed, snow and hurricane fan]

Can't find the X post, which would save attachment usage, but the Equatorial and S Atlantic temps are trending cooler related to the MDR SSTs, or the AMM is going more positive.  Which favors rising motion of the MDR, and lighter trades.

[Stormchaserchuck1]

^That's one heck of a -PDO! approaching +5c anomalies.  I did some work in the beginning of this thread, linking -PDO with increased activity, and it was a just a question of if it would hold for Aug-Sept-Oct. It appears we are well on that way.  Another thing with the PDO is, it has a Summer/Fall correlation with 500mb SE Canada ridging, which is the typical pattern for Gulf of Mexico hits, as storms track more E->W under the ridge

https://ibb.co/bBzXWtq (correlation is default positive, so opposite)

The PDO actually historically correlates with favorable/unfavorable H5 patterns more than ENSO does. 

[GaWx]

 I just did an analysis of CONUS landfalls for RONI ASO -0.50 to -1.00 vs sub -1.00. E = east coast and G = Gulf coast including FL Keys; if storm landfalled on both as a H, I counted it as 1/2 E and 1/2 G (1995’s Erin and 2022’s Ian)

ASO RONI -0.50 to -1.00: every season at least 1
1954: 3 (3E)
1955: 2 (2E)
1964: 4 (2E, 2G)
1970: 1 (1G)
1983: 1 (1G)
1995: 2 (0.5E, 1.5G)
1999: 3 (1E, 2G)
2011: 1 (1E)
2017: 3 (3G)
2021: 2 (2G)
AVG: 2.20 (0.95E, 1.25G)

ASO RONI sub -1.00: less active avg despite 2020
1973: 0
1975: 1 (1G)
1988: 1 (1G)
1998: 3 (1E, 2G)
2007: 1 (1G)
2010: 0
2016: 2 (1E, 1G)
2020: 6 (1E, 5G)
2022: 2 (1.5E, 0.5G)
AVG: 1.78 (0.50E, 1.28G)

Analysis of ASO RONI wk vs mod+:
-sig. more CONUS H landfalls (100%/70% had 1+/2+)
-sig. more E coast landfalls (60%/30% had 1+/2+)
-slightly fewer G coast landfalls due to 2020 being active
-E being nearly as active as G for wk is relatively high for E
-2020 ASO is mod+ per RONI but is only wk per ONI

H tracks:
https://www.nhc.noaa.gov/data/

RONI: https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

[GaWx]

 Check this tweet out from met. Ben Noll as it actually has a prog of RONI, the first I’ve ever seen:

 https://twitter.com/BenNollWeather/status/1793235394219434190

”In a warming world, it's becoming increasingly difficult to disentangle El Niño events from the climate change signal. In other words, when the entire equatorial Pacific Ocean is anomalously warm -like it was in recent months- it can be hard to distinguish the signal from the noise! The Relative Niño 3.4 Index is calculated by subtracting the tropical mean sea surface temperature anomaly (20˚N-20˚S) from the Niño 3.4 Index and multiplying by a scaling factor.

The relative index describes the onset of convection better, is not contaminated by global warming, and can be monitored and forecast in real-time.
 

This suggests that La Niña-like atmospheric patterns may build in the months ahead, likely starting before an official La Niña event is classified by most international centers. This is of significance to hurricane season in the Atlantic Ocean and weather patterns across the planet.

—————————————
This ONI/RONI prog is from the C3S, an average of most of the major models of the world (see image below). It’s showing RONI-ONI to be -0.67 in May (near what it was in FMA) and -0.55 in Oct. Based on this graph, it’s showing a prog of ASO ONI to be ~-0.60 (weak La Niña) but ASO RONI to be ~-1.15 (moderate La Niña), a truer reflection of the predicted strength of La Niña since it is negating the surrounding tropical waters’ warming:

 

RONI retrospectively calculated back to 1950:

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

[WxWatcher007]

59 minutes ago, GaWx said:

 Check this tweet out from met. Ben Noll as it actually has a prog of RONI, the first I’ve ever seen:

 https://twitter.com/BenNollWeather/status/1793235394219434190

”In a warming world, it's becoming increasingly difficult to disentangle El Niño events from the climate change signal. In other words, when the entire equatorial Pacific Ocean is anomalously warm -like it was in recent months- it can be hard to distinguish the signal from the noise! The Relative Niño 3.4 Index is calculated by subtracting the tropical mean sea surface temperature anomaly (20˚N-20˚S) from the Niño 3.4 Index and multiplying by a scaling factor.

The relative index describes the onset of convection better, is not contaminated by global warming, and can be monitored and forecast in real-time.
 

This suggests that La Niña-like atmospheric patterns may build in the months ahead, likely starting before an official La Niña event is classified by most international centers. This is of significance to hurricane season in the Atlantic Ocean and weather patterns across the planet.

—————————————
This ONI/RONI prog is from the C3S, an average of most of the major models of the world (see image below). It’s showing RONI-ONI to be -0.67 in May (near what it was in FMA) and -0.55 in Oct. Based on this graph, it’s showing a prog of ASO ONI to be ~-0.60 (weak La Niña) but ASO RONI to be ~-1.15 (moderate La Niña), a truer reflection of the predicted strength of La Niña since it is negating the surrounding tropical waters’ warming:

 

RONI retrospectively calculated back to 1950:

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

Does that change your analysis at all?

[GaWx]

25 minutes ago, WxWatcher007 said:

Does that change your analysis at all?

 No, it doesn't change my analysis at all as that analysis wasn't predicting the upcoming La Nina strength.

 Nothing in this Noll tweet is surprising except that I had never seen a prog of RONI until now. Of course, this is just a multimodel avg prog and thus we'll obviously need to see if it verifies well. But this prog of a moderate RONI based La Nina in ASO (-1.15) doesn't surprise me at all as I had already been thinking good chance for RONI based moderate La Nina by ASO.

[brooklynwx99]

holy crap

[LongBeachSurfFreak]

12 hours ago, brooklynwx99 said:

holy crap

Fully expect a parade of majors in the mdr. Maybe even multiple cat 5s. Historic season incoming.

[WxWatcher007]

14 hours ago, brooklynwx99 said:

holy crap

Yup. May 23rd…

 

 

Extreme warmth both in extent and depth across the basin, classic AMO, patterns reinforcing weaker trades, and a coming Nina to abate shear. 

It’s definitely time to think big about 2024. 

 

[AlexD1990]

NOAA releases most aggressive May hurricane forecast ever:

https://www.washingtonpost.com/weather/2024/05/23/hurricane-season-forecast-active-storms/

[WxWatcher007]

Most of the big factors for a hyperactive season seem baked in, but I suppose a fail mode could be wave breaking imparting shear frequently during peak season. Similar to what we saw a few years ago. That said, I think that’s unlikely. 

[Stormchaserchuck1]

We did see a trend break 2 years ago when there were 14 NS and 2 MH in a La Nina year. I'm not saying the same thing will happen again, but a lot has to go right to get 20+..  

[WxWatcher007]

4 hours ago, Stormchaserchuck1 said:

We did see a trend break 2 years ago when there were 14 NS and 2 MH in a La Nina year. I'm not saying the same thing will happen again, but a lot has to go right to get 20+..  

You’re right about a lot needing to go right for 20+. I think the trend the last few years and the extraordinary base state of the basin this season would have me shocked if it didn’t happen. Of course, we know a fair number of NS end up debatable anyway.

It’s the H and MH numbers for me. The key question IMO is whether an active WAM causes a feedback of strong SAL bursts that reduce instability in the tropical Atlantic. If not, I think we threaten records. Even if it does, I’d be surprised if this isn’t a top 10 season for activity. 

[GaWx]

 The following tweet’s image clearly illustrates the idea of RONI, which is already nearing the -0.5 threshold of La Niña (look at all of the blue along the equator in the E and C Pacific) vs the equivalent to ONI, which is still only down to ~+0.2 per OISST and CRW. 
 

https://x.com/BenNollWeather/status/1793981601132798393

“This map compares current sea surface temperature anomalies with the global average anomaly. Rather than using a 30-year normal to compute anomalies, this method more clearly reveals areas that are unusually warm or cool relative to the rest of the planet. This is important”

 

[lee59]

Long Island certainly overdue for a land falling hurricane. Last one was Gloria in 1985.

[LongBeachSurfFreak]

45 minutes ago, lee59 said:

Long Island certainly overdue for a land falling hurricane. Last one was Gloria in 1985.

They tend to come in bunches. 54 had 3 events produce hurricane force winds on Long Island. Carol, Edna and hazel. It really comes down to the pattern. If we end up in a landfall pattern for the north east this season it could get real serious. 38 today, would be a 100+ billion dollar disaster 

[WxWatcher007]

2 hours ago, LongBeachSurfFreak said:

They tend to come in bunches. 54 had 3 events produce hurricane force winds on Long Island. Carol, Edna and hazel. It really comes down to the pattern. If we end up in a landfall pattern for the north east this season it could get real serious. 38 today, would be a 100+ billion dollar disaster 

I think it’s been fairly active in recent years, we just haven’t had a hurricane or truly classic pattern outside maybe Isaias. Obviously not the bunches you talk about though in a single season.

Atlantic Canada has been really hot as well recently. I can’t imagine a ‘54 like season. That was insane. 

[WxWatcher007]

First wave of the season is pretty sharp. Not likely to amount to much but interesting to look at. 

[calm_days]

On 5/23/2024 at 10:31 AM, WxWatcher007 said:

 

Yes; there are even currently two west-to-east lows in the region with trough structure.  That is a contintent-sized anomalous heat so maybe it is generating a more continental weather pattern?? 

[40/70 Benchmark]

I feel like this insanely warm MDR is going to lead to some Hugo type evolutions, whereas they get really intense really fast and far to the east....thus while peak intensity in terms of wind is out over the fish, we end up with some dreadful storm surges from land falling, expansive post EWRC systems.

This is why I actually feel like we may not see the barrage on intense landfall in terms of max sustained winds that some may expect, but as we know the surge is the most dangerous aspect. And of course, always in the look out for home-brew systems that can spin up fast at close range...those could threaten with particularly intense landfalls in terms of wind.

[CheeselandSkies]

On 5/25/2024 at 11:24 AM, 40/70 Benchmark said:

I feel like this insanely warm MDR is going to lead to some Hugo type evolutions, whereas they get really intense really fast and far to the east....thus while peak intensity in terms of wind is out over the fish, we end up with some dreadful storm surges from land falling, expansive post EWRC systems.

This is why I actually feel like we may not see the barrage on intense landfall in terms of max sustained winds that some may expect, but as we know the surge is the most dangerous aspect. And of course, always in the look out for home-brew systems that can spin up fast at close range...those could threaten with particularly intense landfalls in terms of wind.

Yup...seems it's always in the close-in quick RI'ers that make the 130kt+ landfalls...Michael, Ida, Ian, etc. The 10-day basin crossing ACE machines like Ivan and Irma are less likely to be as intense at U.S. landfall (if they make one), even if multiple model runs and NHC advisories call for them to be. Hugo was actually something of an anomaly in that regard, remaining a 115-120kt (sources seem to vary) Cat. 4 at time of SC landfall.

[Ed, snow and hurricane fan]

Super premature, but the September CanSips 500 mb heights looks downright scary, in a season with possible 10 or more hurricanes, for the Central and Eastern Gulf.  Had to check, 42035 at 85F, averaging about 82F diurnally the last couple of days, is warm for so early, but if CanSips is right, MBY is in good shape.

 

Being 60, fat, and on a CPAP, Ike was an adventure, any hurricane now would be an uncomfortable drudgery.

[WxWatcher007]

8 hours ago, CheeselandSkies said:

Yup...seems it's always in the close-in quick RI'ers that make the 130kt+ landfalls...Michael, Ida, Ian, etc. The 10-day basin crossing ACE machines like Ivan and Irma are less likely to be as intense at U.S. landfall (if they make one), even if multiple model runs and NHC advisories call for them to be. Hugo was actually something of an anomaly in that regard, remaining a 115-120kt (sources seem to vary) Cat. 4 at time of SC landfall.

Yep—iirc all the landfalling 5s were not even hurricanes 72 hours before landfall.