2024 Global Model Runs Discussion (Out thru day 16)

[Stratton23]

GFS. has a similar disturbance to the EURO in the NW gulf in 8-9 days, worth watching

[skyline385]

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

https://i.imgur.com/gQjTGAq.png

Similar support today

https://i.imgur.com/nLeXsgF.png

Support continues

[Stormlover70]

8 to 9 days out says it all.

[TomballEd]

10 or 20% of the ensemble members showing widely scattered (all over the basin) TCs is not that much model support.

The one exception is the 5 TCs seen by Euro ensemble members clustered fairly close together in the Caribbean. A suggestion of something by Euro ensembles Central Atlantic after day 10. I see a lot of 1010 or higher members not in a hurry to strengthen, those don't count in my book but there are some members with solid TS/H. Or, it is waking up but no switch is being thrown in the next week.

[Stratton23]

The switch is coming and i expect ensemble guidance to continue to grow, its been growing every run especially on the EPS

[toad strangler]

The switch is coming and i expect ensemble guidance to continue to grow, its been growing every run especially on the EPS

There has been two hurricanes this month, with one of them still active. If anything, it's just the models being wrong more so than a seasonal switch flip in less dynamic indicator seasons.

[skyline385]

8 to 9 days out says it all.

Yep that is standard time frame for ensemble signals, these arent deterministic runs.

[skyline385]

The switch is coming and i expect ensemble guidance to continue to grow, its been growing every run especially on the EPS

There has been two hurricanes this month, with one of them still active. If anything, it's just the models being wrong more so than a seasonal switch flip in less dynamic indicator seasons.

Both signals for the systems this month were caught on by models and ensembles well in advance.

[LarryWx]

The switch is coming and i expect ensemble guidance to continue to grow, its been growing every run especially on the EPS

There has been two hurricanes this month, with one of them still active. If anything, it's just the models being wrong more so than a seasonal switch flip in less dynamic indicator seasons.

Agreed, it has been a very active season and Aug so far.
1) 2024 is currently at 47 ACE vs 15 avg for 8/15 season to date for the very active 1991-2020. It is projected to be at ~57 through 8/19 vs 18 avg of the active era. Aug, itself, is projected to be at ~21 MTD through 8/19 vs 8 avg for 1991-2020.
2) August has had TCs on 10 of the 1st 16 days and that is expected to be at 13 of the 1st 19 days.

[wxman57]

Peak season isn't far off, and I'm quite pleased, amazed actually, that the models are not showing much activity. That's perfectly fine with me. We have lowered our predicted numbers to 19/8/5 from 23/12/6 earlier in June. That's an additional 14 named storms, which is much more reasonable than another 18, given the state of the tropics. New Euro seasonal is predicting normal activity for Sept-Nov. La Nina just can't get going, and the deep tropics just don't seem as favorable as expected. Also, the Azores-Bermuda high is weaker than predicted, allowing for storms (like Ernesto) to recurve earlier. I'd be quite happy if Ernesto was the last storm of the season, though I doubt that will be the case. My internal office hurricane contest numbers are 17/8/4 (from May).

[Teban54]

and the deep tropics just don't seem as favorable as expected.

The deep tropics is almost never favorable in mid-August, no? If anything, the existence of Beryl should have shown that it was much more favorable than it typically would be.

[WeatherBoy2000]

Peak season isn't far off, and I'm quite pleased, amazed actually, that the models are not showing much activity. That's perfectly fine with me. We have lowered our predicted numbers to 19/8/5 from 23/12/6 earlier in June. That's an additional 14 named storms, which is much more reasonable than another 18, given the state of the tropics. New Euro seasonal is predicting normal activity for Sept-Nov. La Nina just can't get going, and the deep tropics just don't seem as favorable as expected. Also, the Azores-Bermuda high is weaker than predicted, allowing for storms (like Ernesto) to recurve earlier. I'd be quite happy if Ernesto was the last storm of the season, though I doubt that will be the case. My internal office hurricane contest numbers are 17/8/4 (from May).

I agree with the storm count reduction. This year hasn't fallen in line with many recent years of pumping out short lived TSs left and right, this looks to continue. I think we're on track for a 2017 like season which was a quality over quantity output year.

[SFLcane]

Peak season isn't far off, and I'm quite pleased, amazed actually, that the models are not showing much activity. That's perfectly fine with me. We have lowered our predicted numbers to 19/8/5 from 23/12/6 earlier in June. That's an additional 14 named storms, which is much more reasonable than another 18, given the state of the tropics. New Euro seasonal is predicting normal activity for Sept-Nov. La Nina just can't get going, and the deep tropics just don't seem as favorable as expected. Also, the Azores-Bermuda high is weaker than predicted, allowing for storms (like Ernesto) to recurve earlier. I'd be quite happy if Ernesto was the last storm of the season, though I doubt that will be the case. My internal office hurricane contest numbers are 17/8/4 (from May).

There is still plenty of season left we have already had 3 hurricanes and 1 major thats one heck of start for any yr. nearly 85% of all majors i am sure you know occur after 8/20. With a an intensifying la nina we should tracking storms late into November especially in the caribbean. Regarding the bermuda high yes it has been weak for ernesto and we still managed to have impacts in the caribbean. With a +NAO heading into September models show the ridge building quite strong across the tropical atlantic.

[SFLcane]

To add to my post above all 3 hurricanes that have developed have impacted land thus far whether thats a trend who knows.

[SFLcane]

[skyline385]

and the deep tropics just don't seem as favorable as expected.

The deep tropics is almost never favorable in mid-August, no? If anything, the existence of Beryl should have shown that it was much more favorable than it typically would be.

On another topic, regarding Beryl and deep tropics, any activity in the MDR before August is heavily correlated with an active season so atleast on that front the signal for this season was a giant red flag with a historic C5 in late June. However, it does seem like it will be a more quality focused season rather than a quantity one like we have seen in recent years.

[SFLcane]

and the deep tropics just don't seem as favorable as expected.

The deep tropics is almost never favorable in mid-August, no? If anything, the existence of Beryl should have shown that it was much more favorable than it typically would be.

On another topic, regarding Beryl and deep tropics, any activity in the MDR before August is heavily correlated with an active season so atleast on that front the signal for this season was a giant red flag with a historic C5 in late June. However, it does seem like it will be a more quality focused season rather than a quantity one like we have seen in recent years.

This..especially one that becomes a major.

[Spacecoast]

On one hand...


However, on the other hand....




Really don't know what to think

I suspect that the next 3 weeks will be closer to normal (1-2 H's forming), rather than above normal (3-4 H's forming).

[TomballEd]

Larry knows more about this than I do, but a neutral ENSO will tend to have a weaker B-A ridge than a cold ENSO, if memory serves. Ernesto was *almost* a fish (Virgin Islands, Puerto Rico and probably Bermuda means Ernesto was not a true fish), the Euro weeklies have a strong 'fish' feel.

That said, first week of September Euro suggests recurve may be too late to spare the ECUSA. CFS has the mean trough closer to the Ohio/Mississippi Valleys than the other weeks, which could suggest an ECUSA threat.





CFS image doesn't seem to want to show up.

[LarryWx]

Larry knows more about this than I do, but a neutral ENSO will tend to have a weaker B-A ridge than a cold ENSO, if memory serves. Ernesto was *almost* a fish (Virgin Islands, Puerto Rico and probably Bermuda means Ernesto was not a true fish), the Euro weeklies have a strong 'fish' feel.

That said, first week of September Euro suggests recurve may be too late to spare the ECUSA. CFS has the mean trough closer to the Ohio/Mississippi Valleys than the other weeks, which could suggest an ECUSA threat.

https://charts.ecmwf.int/streaming/20240816-0710/9f/ps2png-worker-commands-754b4646fc-q282z-6fe5cac1a363ec1525f54343b6cc9fd8-mbxwjf8r.png

https://www.tropicaltidbits.com/analysis/models/cfs-avg/2024081600/cfs-avg_z500aMean_us_4.png

CFS image doesn't seem to want to show up.

Hey Ed,
My research suggests a stronger ridge with mid grade moderate to strong La Niña vs weak La Niña. The tracks for weak to low end moderate La Niña during ASO (say -0.5 to -1.2) are ON AVERAGE (every year varies of course) significantly more ominous for the corridor stretching from the Lesser Antilles through the NE Caribbean, Bahamas, SE US, and E GOM vs those for a mid grade moderate to strong Niña in ASO (-1.3-). The stronger Niña ASO seasons have tended to have only a near avg threat for the same areas with somewhat stronger to the SW (MX/S TX/C America), which I attribute to a stronger Bermuda high.

I also found cold neutral in ASO (-0.1 to -0.4) to be only near avg in that LA to E GOM corridor.

What’s recently been scary to me is that the latest RONI forecasts strongly suggest ASO RONI will likely end up in the most dangerous -0.5 to -1.2 range. Keep in mind that there have already been 2 H hits in the corridor with Beryl hitting the LAs and Debby hitting the SE US. There could easily be another 3-4 this season.