2025 Atlantic Hurricane Season

[NorthHillsWx]

2025 ACE is now within about 10 of average. With the two ongoing storms, albeit with Humberto likely to become non tropical today, we will be within single digits of average. I cannot stress enough how impressive this is given how far behind we were just a couple weeks ago

[GaWx]

28 minutes ago, NorthHillsWx said:

2025 ACE is now within about 10 of average. With the two ongoing storms, albeit with Humberto likely to become non tropical today, we will be within single digits of average. I cannot stress enough how impressive this is given how far behind we were just a couple weeks ago

And this general idea of a big ACE comeback has been forecasted for several weeks by the Euro Weeklies. The EW after an upcoming break once Humberto and Imelda dissipate continue to forecast ACE to pick up again as we get to mid and even moreso as we approach late month.

[GaWx]

 Favorable ACE looks to continue through the foreseeable future: (note that favorable phase 2 just produced Humberto and Imelda)

GEFS: going backwards through 2/1/8

 

EPS: going backwards through 2/1/8

[GaWx]

Check this out. It turns out that Humberto and Imelda are the two closest Atlantic hurricanes on record (at 467 miles) other than a highly unreliable two unnamed hurricanes in 1853 (428 miles apart). Next closest of reliable years was Easy and Fox in 1951 (497 miles)!

 

[Roger Smith]

Just like me, they long to be, close to you.

It's a nightmare for European forecasters who are waiting to see what ejects from dying Humberto, model consensus is not that good but something intense could come out and head for Ireland and Scotland Friday-Saturday. Or it could all fizzle out.

[Maestrobjwa]

5 hours ago, GaWx said:

Check this out. It turns out that Humberto and Imelda are the two closest Atlantic hurricanes on record (at 467 miles) other than a highly unreliable two unnamed hurricanes in 1853 (428 miles apart). Next closest of reliable years was Easy and Fox in 1951 (497 miles)!

 

Easy and Fox are the most 1950s names ever, lol

[WxWatcher007]

Took a minute to pull together, but here's my latest analysis. We're far from done. 

Just now, WxWatcher007 said:

We've made it to October, and with Imelda in its final act and just under three weeks left in the peak season forecast, it's time to take a look at what comes next. 

Peak Season Forecast (Aug 20-Oct 20)
Named Storms: 10 (4)
Hurricanes: 6 (3)
Major Hurricanes: 3 (2)

Fernand, Gabrielle (MH), Humberto (MH), Imelda (H)

First, there's still plenty of potential left in the basin. Although climo is quickly shifting westward, we still see robust AEWs moving into the basin, and one of those will actually be an area of interest discussed below. Yes, there is dry air/SAL in the tropical Atlantic, but look at the ITCZ and the convection we have there. This will go a long way toward ensuring the survival of the coming waves. 

 

A key part of what happens the rest of the period will center around intraseasonal forcing. Will the MJO remain in a favorable state for TC genesis and landfall risk? Will we get a CCKW that enhances the opportunity for waves to develop? The signals are mixed, but I think we will remain in a favorable period overall through the end of October. As I stated in my peak season forecast, I still think we rapidly end the season at the end of the month however. 

In terms of getting more NS and H, the basin continues to be primed for it, with SST anomalies still robust throughout the Atlantic. As we shift toward activity in the climo favored spots off the SE coast, Gulf, and Caribbean--especially the western Caribbean, there is plenty of fuel for low to moderate end activity. 

The picture becomes more complicated when looking at high end activity, however. To be sure, there is plenty of OHC, especially in the western part of the basin.

But a deeper look shows that there are more localized regions where higher end activity is more likely. 

 

I don't think this changes much, but we definitely have to watch out for another potential MH if it gets into these zones of anomalously high OHC. 

Finally, we have been extremely lucky that nothing has formed in the Caribbean. Between anomalously high OHC and exceptionally low shear, we've been avoiding disaster--seriously. Now that climo is shifting into this region, we need to closely monitor 1) the development of a CAG by mid-October and 2) any tropical waves getting to the Caribbean. There is a strong signal for anomalously low wind shear to return--though this year has been incredibly conducive in the wind shear category. 

 

Alright, so what are we watching? I have three areas of interest. 

 

1. Tropical Atlantic Wave 
The Tropical Atlantic has been more of a bust this season as expected, in large part due to the prevalence of dry and stable air along with SAL. This has been an issue throughout the decade. However, those conditions are more limited now, and an active wave train has moistened a good part of the MDR. There is a strong cross guidance signal that a wave emerges and finds hospitable conditions in the ITCZ. This should eventually lead to some level of development, as evidenced by the models. I am bullish on development.

 

2. SE Coast/Gulf
This is the second lemon by the NHC, and it's no surprise given that there has been a signal for a few days now. In the wake of Imelda, we have a boundary that is left behind, and along it we have some vorticity trying to spin up. Now, whether that becomes a low is unclear, but we do know that climo starts to favor these kinds of things in October. The limiting factors are proximity to land, and time. Whatever develops should cross Florida and into the Gulf, but is unlikely to meander there with time to develop into anything serious. This probably has a decent chance of development, though not nearly as high as area #1. It's worth a casual eye. 

 

3. Caribbean CAG
This is the one to watch, even though there isn't a significant development signal, yet. Toward the middle of the month, guidance is starting to show the development of a Central American Gyre, which favors slow, but gradual tropical genesis. The CPC has picked up on it, and recent years have shattered the mold on what CAGs can become. Recently, they've become some of our most destructive storms.

With wind shear expected to drop significantly and the thermal environment in the Caribbean, along with the increased tendency for troughing in the east around this time, our next significant threat may very well come from this region. 

 

[Coach McGuirk]

Sandy hit NJ October 29. 

I like how it snowed two days later.  WTF. 

[Low Pressure Lunacy]

10 hours ago, WxWatcher007 said:

Took a minute to pull together, but here's my latest analysis. We're far from done. 

 

Unfortunately you are correct, and I remember someone mentioning the home brew part of the season is up next and it looks like it may have begun. These storms seem to be originating in odd places lately. 

 

And then there is this nasty storm, I really appreciate that the employees at the NHC will keep working even though they won't be paid during the shutdown. Humans, especially most decision makers, are really peculiar and I will never understand them.

[Coach McGuirk]

boring rain storm in Florida. 

[olafminesaw]

Pretty crazy how closely 2015 matches to this season

[Retrobuc]

13 hours ago, Coach McGuirk said:

Sandy hit NJ October 29. 

I like how it snowed two days later.  WTF. 

And the year before Sandy we had a foot of snow on the same weekend.

[Seminole]

2 hours ago, olafminesaw said:

Pretty crazy how closely 2015 matches to this season

2015 was the last year of the Florida 10 year record of no hurricane landfalls. 2016 started a remarkable 8 year stretch of 16 Hurricane landfalls in the gulf coast. Feast or famine as the saying goes.  

[suzook]

17 hours ago, Coach McGuirk said:

Sandy hit NJ October 29. 

I like how it snowed two days later.  WTF. 

I remember that. We had no power either, so no heat too!

[GaWx]

MJO is forecasted to continue to traverse mainly favorable phases meaning a resumption of activity fairly soon wouldn’t be surprising, especially with it being La Niña:

 

[WxWatcher007]

4 hours ago, GaWx said:

MJO is forecasted to continue to traverse mainly favorable phases meaning a resumption of activity fairly soon wouldn’t be surprising, especially with it being La Niña:

 

Thinking the tropical Atlantic wave could be thread worthy tomorrow. Signal for it continues to be robust. 

[GaWx]

52 minutes ago, WxWatcher007 said:

Thinking the tropical Atlantic wave could be thread worthy tomorrow. Signal for it continues to be robust. 

 Would it be possible, for continuity purposes, to incorporate it in the “two lemon” thread since most of the posts, including model output, are for the tropical ATL wave?

[WxWatcher007]

2 hours ago, GaWx said:

 Would it be possible, for continuity purposes, to incorporate it in the “two lemon” thread since most of the posts, including model output, are for the tropical ATL wave?

I’m cool with that. Op would just need to change the title. 

[Newman]

The CAG signal is definitely becoming more pronounced on some of the ensembles looking towards the 10-14 day period, which aligns with the expected MJO progression and climatology. No surprise that the CPC went >40% TC formation probability in this region the week of Oct 15-21.

 

[GaWx]

2 hours ago, Newman said:

The CAG signal is definitely becoming more pronounced on some of the ensembles looking towards the 10-14 day period, which aligns with the expected MJO progression and climatology. No surprise that the CPC went >40% TC formation probability in this region the week of Oct 15-21.

 

 Oct 11-20 TCG W Car. climo says from a generalizing standpoint this far out  that Keys/SW and S tip of FL would be at the most risk in US although each setup is unique:

[bigtenfan]

16 hours ago, WxWatcher007 said:

I’m cool with that. Op would just need to change the title. 

I have never started a topic before 

how do I change the title?

[GaWx]

10 minutes ago, bigtenfan said:

I have never started a topic before 

how do I change the title?

Go to 1st post, choose edit, and then edit title.

[bigtenfan]

Done

THANK YOU

[GaWx]

 Not to minimize TS Chantal, which caused record 24 hour rainfall in some portions of C NC, but will 2025 get through the rest of this season with no Conus hurricane impact for the first season since 2015? The record longest streak with a hurricane impact is 13 seasons (1938-50).

 -Since 1851 there have been 34 (20%) seasons with no Conus H impact on record. Of these 34, these were only 6 during La Niña (1872, 1890, 1892, 1973, 2000, and 2010) vs a much higher 15 during El Niño, which is intuitive. The highest ACE of these 34 was 2010’s 165 (La Niña) followed by 1951’s 126 (El Nino).

-Since 1851 there have been only 6 (3%) seasons with a first Conus H impact on record in Oct or later: all were in Oct and none of these 6 had a second one. None were during La Niña. The highest ACE of these 6 was 1853’s 76 followed by 2002’s 68. So, if 2025 were to join them, it would by a good margin have the highest ACE of this group and would be the first during La Niña:

1853 neutral: Oct 20th (GA) when center passing 40 miles off GA from TC 1st reported ~NW Bahamas

1923 El Nino: Oct 16th (LA) from TCG in the EPAC!

1946 neutral: Oct 7th (W FL pen.) from TCG in NW Caribbean

1968 El Niño: Oct 18th (W FL pen.) from TCG in SW Caribbean (Gladys)

1987 El Niño: Oct 12th (Keys/S FL) from TCG in SW Caribbean (Floyd)

2002 El Niño: Oct 3rd (LA) from TCG in C MDR (Lili)

 

[WxWatcher007]

That’s fascinating stuff 

[GaWx]

 The latest Euro Weeklies are the most active yet in the W Caribbean for the week of 10/13-19 (if I were in the FL pen., especially S half, I’d be a bit concerned for midmonth):

Forecast nearby TC probabilities:

Anomalies vs 2005-24 climo: wow!

 

[WxWatcher007]

1 hour ago, GaWx said:

 The latest Euro Weeklies are the most active yet in the W Caribbean for the week of 10/13-19 (if I were in the FL pen., especially S half, I’d be a bit concerned for midmonth):

Forecast nearby TC probabilities:

Anomalies vs 2005-24 climo: wow!

 

That’s by far the worst spot too given the OHC and reduction in shear. There’s too much shear for the lemon areas in the Gulf right now, but the tropical Atlantic wave is likely to develop given how convectively active it continues to be and the CAG could very well produce 1-2 TCs (more likely 1 imo).