2024 Atlantic Hurricane Season

[StantonParkHoya]

2 hours ago, WxWatcher007 said:

Yeah I wasn’t trying to ask a leading question there. I do think the mid to high 20s NS forecasts will be too high at this point, but I do still believe low 20s is achievable given that I expect activity into November. It’s pretty weird to see so little out there right now, but we’ll just have to see what happens when the lid comes off. 

Interesting you think we’ll have activity in November when we don’t even have activity on August 24th

[WxWatcher007]

7 minutes ago, StantonParkHoya said:

Interesting you think we’ll have activity in November when we don’t even have activity on August 24th

Because they’re entirely different time periods with different climatological setups in the basin? 

This time of year when the MDR is supposed to be lighting up, we’ve seen how SAL and stability in the eastern MDR can suppress August activity in recent years. We’ve also seen how that’s done little to blunt backloaded seasons because late season climo sees the decline of SAL and shift of TC genesis to the Caribbean and western Atlantic. Shear is more an issue late season normally, and that’s unlikely to be as much a roadblock this season given either a cool neutral or weak Nina ENSO state. 

2022 had no activity between early July and early September but had 3 H in November. In active seasons there’s usually some activity in November. Including 2017, 5 of the last 7 seasons have had activity in November. 

If you told me a weak Nino were on the table late season like last year, November activity is off the table even with historically warm SSTs/OHC, but that’s not what we have. 

[Jebman]

We are getting lucky this season. If we can get thru Sept with very little hurricane activity, then maybe the rest of the season will be the same, more like a Nino tropic presentation than a La Nina setup.

[GaWx]

1 hour ago, Jebman said:

We are getting lucky this season. If we can get thru Sept with very little hurricane activity, then maybe the rest of the season will be the same, more like a Nino tropic presentation than a La Nina setup.

 But the CONUS has already had 2 H landfalls and it’s still pretty early. That’s pretty rare for this early. Since 1950 only 2020, 2005, 2004, 1986, 1985, and 1959 had 2+ CONUS H landfalls by Aug 31st.

[GaWx]

 The tropics look like they may get active again in just over a week. If so, that would mean the quiet period would end up under 2 weeks long. Not long at all unfortunately.

[StantonParkHoya]

Think we may need to reposition focus from the MDR. There’s a little home grown deal consistently showing up on the OP GFS near Florida on Labor Day.

[tiger_deF]

Frankly I’m more concerned with making it to 15 NS if that, GFS shows nothing right through the peak of the season September 10th…
 

Effectively the first entire half of the true peak (Mid August-Sept 10) will be 1/1/0. Something out there is deeply unfavorable, maybe the combination of SAL and the ICTZ being North has been the culprit. Either way the climo model runs have been busting hilariously over the past few weeks.

 

[Floydbuster]

It is the ITCZ absolutely shunting and blowing waves apart to the north. What the heck is going on?

[StantonParkHoya]

23 minutes ago, Floydbuster said:

It is the ITCZ absolutely shunting and blowing waves apart to the north. What the heck is going on?

Sub 26 water temps, SAL, etc

[Brian5671]

The forecasts with a large # of total storms look to be in serious trouble.  Wonder if the weaker than expected Nina also playing  role in less storm formation.

[Windspeed]

It is the ITCZ absolutely shunting and blowing waves apart to the north. What the heck is going on?

Mike, where have you been? Lol... There's been plenty of discussion about the West African Monsoon and latitudinal placement. AEWs do not, or at least rarely, develop north of the CVs when they exit there. That being said, the WAM is losing steam, and it is modeled to do so. ITCZ placement should drop in latitude by September, and the SPH will shift into a more climatogical steering flow for MDR TCs.

I actually think it is somewhat amusing that TC enthusiasts and pro tropical climatologists are all scrambling due to the approaching peak with limited model support. This is mostly due to varying ranges of significantly high named storms numbers. I think forecasting 25+ named storms is a huge risk to take in any year no matter the long-range ECMWF+UKMET superblends, climo patterns, or AMO or ENSO states. Too many caveats and anomolies can occur when all things look extreme. WAM placement and East Atlantic Nino being a perfect example this year. I should stress, however, that WAM will weaken, even if it is abnormally strong. You want some monsoonal enhancement to favor AEWs with a low-latitude ITCZ if you want MDR TCs. We're still going to get that the bulk of September. Sure, NS numbers may not hit all these crazy forecasts, but we will get active, and we will see intense TCs out of the MDR during that stretch.

Back to the present, though the wave south of the CV looks good, modeling support is pretty limited. However, it doesn't look too bad right now, and bears watching. As it moves into the western MDR this coming week, the MJO may time just right to enhance development. Even if limited, some EPS support is there, and that could increase as we get into midweek.

[Floydbuster]

13 minutes ago, Windspeed said:

 

Mike, where have you been? Lol... There's been plenty of discussion about the West African Monsoon and latitudinal placement. AEWs do not, or at least rarely, develop north of the CVs when they exit there. That being said, the WAM is losing steam, and it is modeled to do so. ITCZ placement should drop in latitude by September, and the SPH will shift into a more climatogical steering flow for MDR TCs.

I actually think it is somewhat amusing that TC enthusiasts and pro tropical climatologists are all scrambling due to the approaching peak with limited model support. This is mostly due to varying ranges of significantly high named storms numbers. I think forecasting 25+ named storms is a huge risk to take in any year no matter the long-range ECMWF+UKMET superblends, climo patterns, or AMO or ENSO states. Too many caveats and anomolies can occur when all things look extreme. WAM placement and East Atlantic Nino being a perfect example this year. I should stress, however, that WAM will weaken, even if it is abnormally strong. You want some monsoonal enhancement to favor AEWs with a low-latitude ITCZ if you want MDR TCs. We're still going to get that the bulk of September. Sure, NS numbers may not hit all these crazy forecasts, but we will get active, and we will see intense TCs out of the MDR during that stretch.

Back to the present, though the wave south of the CV looks good, modeling support is pretty limited. However, it doesn't look too bad right now, and bears watching. As it moves into the western MDR this coming week, the MJO may time just right to enhance development. Even if limited, some EPS support is there, and that could increase as we get into midweek.

 

 

I absolutely still expect a very busy season, I'm just curious after the waves in July that led to Beryl, Debby and Ernesto being so low latitude as to why it occurred so suddenly once Ernesto formed. I also think the MJO in mid September may light things alive quite a bit. 

[Windspeed]

 
I absolutely still expect a very busy season, I'm just curious after the waves in July that led to Beryl, Debby and Ernesto being so low latitude as to why it occurred so suddenly once Ernesto formed. I also think the MJO in mid September may light things alive quite a bit. 

WAM intensified and gained significant latitude in late July. The Sub-Saharan region, even portions of the Sahara have seen significant precipitation the past month. But if you recall, the ITCZ was at a low latitude and very active in June before WAM intensified.

We have seen record downpours from the Arabian Peninsula to Morocco over the past month. Additionally, we've seen enhanced SAL plumes due to SPH placement across the central Atlantic. You may also recall that the AEWs that became Debby and Ernesto did not become convectively dominate until they reached the WATL. Both systems were choked of stable airmass. They eventually did moderate and develop, but only after mixing out SAL.

[ldub23]

9 minutes ago, CurlyHeadBarrett said:

bring on 2025

Oct/Nov will be  big this year with several strong storms forming  in the central Atlantic  ocean but  its  doubtful they will get as far west as  300 miles east of  Bermuda. 2025 cant  be worse than this season unless the  muti-year  pattern of a dead MDR continues.

[Windspeed]

17 minutes ago, ldub23 said:

Oct/Nov will be  big this year with several strong storms forming  in the central Atlantic  ocean but  its  doubtful they will get as far west as  300 miles east of  Bermuda. 2025 cant  be worse than this season unless the  muti-year  pattern of a dead MDR continues.

LOL, nice try. We had a Category 5 hurricane in the MDR last year. We've already had a Category 5 hurricane that developed out of the MDR this year. 

[ldub23]

2 minutes ago, Windspeed said:

9 minutes ago, ldub23 said:

Oct/Nov will be  big this year with several strong storms forming  in the central Atlantic  ocean but  its  doubtful they will get as far west as  300 miles east of  Bermuda. 2025 cant  be worse than this season unless the  muti-year  pattern of a dead MDR continues.

LOL, nice try. We had a Category 5 hurricane in the MDR last year. We've already had a Category 5 hurricane that developed out of the MDR this year. *eyeroll*

And since we  have  had 2 cloudless waves that couldnt do anything in the MDR. The MDR has done  nothing since Beryl. In 2023  it was a  1 storm MDR season like this year. All the  others were very weak storms that  dissipated  over water. Franklin couldnt get  going till far  north of the MDR. No one thinks  last  year was an active  MDR season

 

[yoda]

Intriguing discussion by Webb

 

 

[Windspeed]

And since we  have  had 2 cloudless waves that couldnt do anything in the MDR. The MDR has done  nothing since Beryl. In 2023  it was a  1 storm MDR season like this year. All the  others were very weak storms that  dissipated  over water. Franklin couldnt get  going till far  north of the MDR. No one thinks  last  year was an active  MDR season
 

Your only criteria for an "active MDR" only ever appears to be when we have a major hurricane in progress, and your posts are uncoincidentally absent. Only the 2021 season lacked a classifed TC in the MDR that failed to become a hurricane. 2023 saw four, one becoming a Category 5 while still in the MDR. The MDR is not going to produce long-tracking major hurricanes every season. Yes, we all know this. I'm not even sure why I bothered a response. Perhaps for everyone else who doesn't know your history and might become misinformed.

[jburns]

This gets us to Sept.

 

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Sun Aug 25 2024

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Tropical cyclone formation is not expected during the next 7 days. 

$$
Forecaster Brown
NNNN

[GaWx]

 Euro Weeklies are still not giving in to more active. Sunday’s had member mean of 27 ACE for the next 4 weeks vs 1991-2020 avg of 58. If relative quiet were to verify, they’d deserve major kudos for being so persistent. Regardless, they’re still calling for some activity and not anywhere near dead.

[GaWx]

The 3 main 0Z ensemble agree that the highest concentration of members with a TCG is in the MDR 45-60W between 8/31 and 9/3. Overall concentration looks a bit higher vs most earlier runs. This is pretty close to when/where 21 AI-Euro runs in a row had TCG as well as TCGs on recent ICON runs. Chances seem pretty good but we’ll see.

[Seminole]

Does this potentially factor in with the lack of development in the MDR? 

https://www.msn.com/en-us/weather/topstories/no-one-can-figure-out-why-the-atlantic-ocean-is-cooling-at-record-speed/ar-AA1pcupU

[Windspeed]

Does this potentially factor in with the lack of development in the MDR? 
https://www.msn.com/en-us/weather/topstories/no-one-can-figure-out-why-the-atlantic-ocean-is-cooling-at-record-speed/ar-AA1pcupU

That is referring to the equatorial and meridional Atlantic Niño/Niña SSTa oscillation. Generally, AN SSTs enhance the WAM and ITCZ. BN tends to weaken them. There is a paper on this if you're interested. An Atlantic Niño can enhance the MDR where as a Atlantic Niña can limit the spawn of AEWs. But it's not as impactful versus ENSO's influence and other factors. You can still get an active MDR if meridional SSTs are BN. Atlantic Niño can enhance in combination with -ENSO, but certainly won't counter a moderate +ENSO.

https://cpaess.ucar.edu/meetings/2021/pirata-24/abstracts/atlantic-ni%C3%B1oni%C3%B1a-influences-atlantic-tropical-cyclone-activity

I should also add that the article you posted above isn't also referring to the SSTs across the North Atlantic basin. They are still very much above normal.

[GaWx]

1 hour ago, Seminole said:

Does this potentially factor in with the lack of development in the MDR? 

https://www.msn.com/en-us/weather/topstories/no-one-can-figure-out-why-the-atlantic-ocean-is-cooling-at-record-speed/ar-AA1pcupU

 This and other possible factors have been discussed heavily in recent days over at that favorite other BB. The quick answer is that nobody really knows as there’s disagreement even among pro-mets but that it is probably a combo of factors, some unknown:
 
 1. Your link is referring to an Atlantic La Niña. The record cooling refers to the fastest cooling on record (back to 1982) in the E Atlantic along and near the equator. Keep in mind that on a RONI type of basis, the level of cool there is probably ~0.5C cooler than what the following graph shows. The graph shows something akin to the Pacific ONI, which doesn’t take into account very warm surrounding tropical waters. Anyway, it cooled from Mar to July from an Atlantic Nino +1.15C anom (~+0.65C on RONI type of basis) to on the border of Atlantic Niña -0.5C anom (~-1.0C on RONI type of basis) meaning that it cooled ~1.65C (record pace for 4 month period):

 

 More great stuff on Atlantic La Niña that Webb referred to (this from 2021):

https://cpaess.ucar.edu/sites/default/files/meetings/2020/presentations/kim-presentation.pdf

2. Another possible contributing factor is the record heat in higher latitudes of the Atlantic:

 

 This tweet from late yesterday is from a New Orleans pro-met who specializes in tropical:

 

[Windspeed]

The quick answer is that nobody really knows as there’s disagreement even among pro-mets but that it is probably a combo of factors:

Yes. lol, interestingly enough, the sudden drop in the meridional and equatorial Atlantic doesn't seem to have weakened the WAM at all in July. In fact, WAM did the opposite and dominated. Perhaps one of the strongest in decades, influencing above normal precip across Sub-Saharan, Sahel. But it must be noted that precipitation has been above normal from the Arabian Peninsula to Morocco. So it's not just West African. Something else is going on, but it does look as if WAM is finally weakening or backing off into a more supportive state for lower latitudinal AEWs.

Edit: I should also clarify that if you want MDR TCs during ASO, you actually want there to be an active WAM in June and July but does not go completely away. If you have no WAM, AEWs are significantly limited in frequency and organization to limit MDR TC production. However, as we have seen this past month, an overly aggressive or potent WAM allows AEWs to gain too much latitude. SPH placement still pulls SAL into that region North of the CVs, not to mention cooler SSTs for thermal support.

[GaWx]

17 minutes ago, Windspeed said:

 

Yes. lol, interestingly enough, the sudden drop in the meridional and equatorial Atlantic doesn't seem to have weakened the WAM at all in July. In fact, WAM did the opposite and dominated. Perhaps one of the strongest in decades, influencing above normal precip across Sub-Saharan, Sahel. But it must be noted that precipitation has been above normal from the Arabian Peninsula to Morocco. So it's not just West African. Something else is going on, but it does look as if WAM is finally weakening or backing off into a more supportive state for lower latitudinal AEWs.

 

Lol, we were both posting about ATL Niña at same time.

I think that this combo of factors (ATL Nino, record warm higher latitude ATL warmth, and other factors including unknown) along with considering the near record warm Caribbean/Gulf, the Pacific Niña, and history/analog seasons suggests two things to me to likely occur:

1. Most intense activity/most of remaining ACE will be in W part of basin.

2. A tendency toward a backloaded season

[WxWatcher007]

Good stuff here this morning. The issues with stability in the eastern MDR have been a recurring theme for one reason or another the last few years, so it’s not terribly surprising (though the reasons this year are) that we’re seeing issues again.

That said, I agree that a more backloaded season looks on the table and did so before all this. Problem with activity further west is you need AEWs to not get slaughtered the minute they leave the African coast lol. 

Subjectively it’s a good break for any coastal areas anytime the basin is anomalously dead. And good for my sleep pattern.  

[Seminole]

2 hours ago, Windspeed said:

That is referring to the equatorial and meridional Atlantic Niño/Niña SSTa oscillation. Generally, AN SSTs enhance the WAM and ITCZ. BN tends to weaken them. There is a paper on this if you're interested. An Atlantic Niño can enhance the MDR where as a Atlantic Niña can limit the spawn of AEWs. But it's not as impactful versus ENSO's influence and other factors. You can still get an active MDR if meridional SSTs are BN. Atlantic Niño can enhance in combination with -ENSO, but certainly won't counter a moderate +ENSO.

https://cpaess.ucar.edu/meetings/2021/pirata-24/abstracts/atlantic-ni%C3%B1oni%C3%B1a-influences-atlantic-tropical-cyclone-activity

I should also add that the article you posted above isn't also referring to the SSTs across the North Atlantic basin. They are still very much above normal.

Very interesting read. The conclusion is that moderate TC activity occurs during this type of environmental setup. The data in the study is for 71 years. I don't think its a leap to postulate that rapid unprecedented ATL Nina cooling could swing the overall trend into the low/no TC genesis category.        

[GaWx]

 Regarding the AEW/activity in the far E ATL on the 12Z runs:

1. ICON at 180 has a TS at 19N/59W moving WNW aimed N of the Leewards. It has had a sfc low from this since the 12Z 8/23 run.

2. GFS has it but doesn’t develop it til it gets to the Gulf on 9/9. It then ends the run as a H just offshore from Apalachicola, FL, about to landfall near there.

3. GEFS: active like 6Z with the lead wave along with some members developing the followup MDR wave.

4. CMC: has a weak reflection of this same AEW at the surface (stronger than 0Z run) that moves WNW to S Bahamas at 240. 

5. UKMET: no TCG

6. Euro: not out yet

[GaWx]

12Z Euro: from main AEW being tracked has a TS just SW of PR moving WNW at 240 hrs