2024 Global Model Runs Discussion (Out thru day 16)

[Category5Kaiju]

The times we've seen the "big" TC outbreaks, I've never seen the models accurately predict them 10 days out.

When was the last time a major, high-profile storm in recent times was correctly predicted that far out? Was it Ian?

[Hurricane2022]

The times we've seen the "big" TC outbreaks, I've never seen the models accurately predict them 10 days out.

When was the last time a major, high-profile storm in recent times was correctly predicted that far out? Was it Ian?

Lee? STY Surigae?

[Hurricaneman]

Some of the Euro ensembles show possibilities with the wave over Mali past day 12 so it may be one to watch

[TomballEd]

Starting out past 300 hours, both the GFS ensembles and Euro ensembles have some very weak members (1010 mb, +/- a couple of mb). They are close to Africa, the ensembles sometimes show very weak systems that are part of the ITCZ/MT that stay just off Africa, Or maybe they are seeing a wave. But for the next 10 days, after Ernesto leaves, I don't think there will be any activity. The 4 week Euro loner range ensemble probabilities beyond 2 weeks show a small area of very low chances (<10%) in a small area in the Gulf and a larger area from ECUSA to the mid-Atlantic to N of the Greater Antilles. An area of 10-15% are well offshore ECUSA. The pattern suggests a persistent trough in Midwest or East Coast.

I think well above normal ACE is still very possible, maybe not to CSU forecast levels, I suspect 2024 has fewer than 20 NS but I still think conditions are too good for the season to still be above normal. Just not as above normal as the Spring forecasts predicted.

[TomballEd]

Jim Cantore on Twitter/X watching mid Atlantic wave despite lack of model support. The wave does look pretty good. GFS analysis suggests the wave is embedded in pretty dry air. It should have favorable shear. Cantore says this is the time of year for short fuse TC development. If it forms, it would follow Ernesto and turn right, if the seedling can survive, maybe the W. Caribbean, but I still think 10 days w/o a NS. But I'll keep blob watching.

[SFLcane]

Starting out past 300 hours, both the GFS ensembles and Euro ensembles have some very weak members (1010 mb, +/- a couple of mb). They are close to Africa, the ensembles sometimes show very weak systems that are part of the ITCZ/MT that stay just off Africa, Or maybe they are seeing a wave. But for the next 10 days, after Ernesto leaves, I don't think there will be any activity. The 4 week Euro loner range ensemble probabilities beyond 2 weeks show a small area of very low chances (<10%) in a small area in the Gulf and a larger area from ECUSA to the mid-Atlantic to N of the Greater Antilles. An area of 10-15% are well offshore ECUSA. The pattern suggests a persistent trough in Midwest or East Coast.

I think well above normal ACE is still very possible, maybe not to CSU forecast levels, I suspect 2024 has fewer than 20 NS but I still think conditions are too good for the season to still be above normal. Just not as above normal as the Spring forecasts predicted.

Actually models suggest quite the expansive ridge "+NAO" building across the tropical atlantic as we get deeper into Aug to start sept.

[Steve]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

[SFLcane]

Just throwing this out there long-range " use with caution" GEFS taking us into peak with a +NAO.. We shall see what happens.

[jlauderdal]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/BOMM_BC.png

13 weeks gets us into the first week of September, CSU calling for 23 NS and we have had 5. 18 storms in 13 weeks, not buying it, my 19 NS might be high but we will see. The math is the math . I would take my 19 down to 17 if I had a redo, less storms but same ACE.

[Teban54]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/BOMM_BC.png

13 weeks gets us into the first week of September, CSU calling for 23 NS and we have had 5. 18 storms in 13 weeks, not buying it, my 19 NS might be high but we will see. The math is the math . I would take my 19 down to 17 if I had a redo, less storms but same ACE.

2019 was only on the B storm on this date, and had 16 storms thereafter. 2021 had 14 storms after August 15, 2023 had 15, and 2010 had 16.

I think most people would agree that those years had less favorable conditions than 2024 (with the arguable exception of 2010).

[Steve]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/BOMM_BC.png

13 weeks gets us into the first week of September, CSU calling for 23 NS and we have had 5. 18 storms in 13 weeks, not buying it, my 19 NS might be high but we will see. The math is the math . I would take my 19 down to 17 if I had a redo, less storms but same ACE.

Gonna take some simultaneous systems to get there. I'm not sure where we are as far as named storm days or hurricane days so far, but CSU called for 120 named storm days and 50 hurricane days. I'm assuming we're roughly 15-20 into NS and probably 5 or 6 into H days. If that assumption is close, there are 108 days until November 30th though we know that most of November won't feature activity (might be one or two ocean systems or in the Caribbean due to the La Nina). We would have 100 named storm days to go which is about a constant system between now and the end of the season adjusted by however many simultaneous storms there are to offset the days without any named storms.

I don't have an opinion one way or the other on this. There are times when bursts bring on 2, 3 or even 4 systems. But there are usually only a couple of these a season that even features those. So it's all a big ? to me until we hit 4-5 weeks from now and see what we are dealing with numbers wise.

[toad strangler]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/BOMM_BC.png

13 weeks gets us into the first week of September, CSU calling for 23 NS and we have had 5. 18 storms in 13 weeks, not buying it, my 19 NS might be high but we will see. The math is the math . I would take my 19 down to 17 if I had a redo, less storms but same ACE.

Gonna take some simultaneous systems to get there. I'm not sure where we are as far as named storm days or hurricane days so far, but CSU called for 120 named storm days and 50 hurricane days. I'm assuming we're roughly 15-20 into NS and probably 5 or 6 into H days. If that assumption is close, there are 108 days until November 30th though we know that most of November won't feature activity (might be one or two ocean systems or in the Caribbean due to the La Nina). We would have 100 named storm days to go which is about a constant system between now and the end of the season adjusted by however many simultaneous storms there are to offset the days without any named storms.

I don't have an opinion one way or the other on this. There are times when bursts bring on 2, 3 or even 4 systems. But there are usually only a couple of these a season that even features those. So it's all a big ? to me until we hit 4-5 weeks from now and see what we are dealing with numbers wise.

As of 03:00 MT this morning .... climatology norm 1991 - 2020 in ()
18.5 NS days (11.9)
6.5 H days (2.2)
42.2 ACE (14.1 AVG)
4.5 MH days (0.4)

[TomballEd]

Starting out past 300 hours, both the GFS ensembles and Euro ensembles have some very weak members (1010 mb, +/- a couple of mb). They are close to Africa, the ensembles sometimes show very weak systems that are part of the ITCZ/MT that stay just off Africa, Or maybe they are seeing a wave. But for the next 10 days, after Ernesto leaves, I don't think there will be any activity. The 4 week Euro loner range ensemble probabilities beyond 2 weeks show a small area of very low chances (<10%) in a small area in the Gulf and a larger area from ECUSA to the mid-Atlantic to N of the Greater Antilles. An area of 10-15% are well offshore ECUSA. The pattern suggests a persistent trough in Midwest or East Coast.

I think well above normal ACE is still very possible, maybe not to CSU forecast levels, I suspect 2024 has fewer than 20 NS but I still think conditions are too good for the season to still be above normal. Just not as above normal as the Spring forecasts predicted.

Actually models suggest quite the expansive ridge "+NAO" building across the tropical atlantic as we get deeper into Aug to start sept.

https://i.postimg.cc/sfhhNcgV/ssss.png

https://i.postimg.cc/5N5Fx2zT/nnnn.png

The suggestion of a Midwest or Eastern trough late August/early September was based on the Euro 4 week TS probabilities. I'd love to be able to see the Euro ensemble 27 day heights. I can see weekly anomalies, and except for one week in September when heights are high over the NE USA, they'd support recurves near the coast or offshore, I'm using the ECMWF site, I'm between PPV model subscriptions. The interesting week and what the other weeks look like.

[chaser1]

Most of the globals' MJO has the index rounding the circle toward 5-6-7 which is part of the reason why they're not anticipating much in the mid-term. Looks like Phase 4 in the early 20's of August. However, the bias corrected Australian (BOMM) cuts from 5 back across the circle to almost 2 by the end of the first week of September. If this is right, expect a burst around then. I still think it will look differently than what it does as of 8/12 which should update in a few hours.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/BOMM_BC.png

13 weeks gets us into the first week of September, CSU calling for 23 NS and we have had 5. 18 storms in 13 weeks, not buying it, my 19 NS might be high but we will see. The math is the math . I would take my 19 down to 17 if I had a redo, less storms but same ACE.

I've been thinking the same about my call for 23 NS, but I still see the potential for a total of 18-20 NS. More importantly is if the majority of those actually reach hurricane intensity as this season thus far has suggested. When I look at the long range 500mb, it sure does imply a potential for a cadre of west longitudinal tracks perhaps even remaining south of the Greater Antilles. That leaves me rather suspicious though. I do not recall a September where numerous storms formed and largely remained Caribbean cruisers. So my next thought goes to the potential that we will in fact continue to see a weakness in the largely amplified Atlantic ridging. Whether that remains along the Eastern Seaboard or retrograded further west to perhaps down toward the Central GOM remains to be seen. The latter has been my big concern since before the season given the anticipation of more storms and stronger storms. I'm still torn whether this will be that type of year where the vast majority of genesis occurs west of 50W or not. That would imply that strong Easterlies and dry air might remain an aspect of this season and ultimately tend to impact ACE I suppose. Worse though is an outcome where there's a concentration of activity a good deal closer to home.

[Stratton23]

And just like that the EPS signal is starting to light up the atlantic basin

[zzzh]

Just like that

[SFLcane]

https://i.imgur.com/TSUwZZU.png
Just like that

[skyline385]

And there's the switch flip coming, just like every year

[Weathertracker96]

https://i.imgur.com/TSUwZZU.png
Just like that

https://i.postimg.cc/763kWVmW/nnn.png

Sorry for the question but does this show steering that favors east coast landfalls?
I know some said troughs were pushing stuff away but just wanted some clarity.

[Stratton23]

No thats alot of ridging, that would favor tracks into the gulf of mexico