Season Comparison (related to indicators, long post)

[Hammy]

This is a very long post so I wanted to give it a separate thread, so I didn't tie up the indicators thread, but moderators can move it there if it best fits.

Since this season isn't going to progress like the typical active seasons (either switch flip on or around Aug 20, or generally continuous/consistent activity) I wanted to look up seasons that had a similar August, and a bit off pacing (for context, this August is at 2/2/0, and 19 ACE

2000: August was dominated by early and mid-month activity, and (aside from Alberto) underperformed expectations--4/2/1 but we had Beryl and Chris which came well under their forecast intensities, the infamous debacle with Debby that was forecast as a Cat 2 or higher into Miami (only to dissipate). Nothing formed after Aug 20, and in fact, save for one short lived tropical storm at the start of September, it was completely dead from August 24 until September 11. The real bell day that year was in late September when we had two major hurricanes over ten days.
August: 4/2/1 and 43 ACE. Rest of season: 11/6/2 and 52 ACE
This season would end at 15/8/3 and 107 ACE.


2001: Nothing in July an August drastically underperformed: Barry failed to reach hurricane intensity despite the forecast, Chantal similarly ran into a lot of shear in the Caribbean, and Dean had two short-lived stints, and after August 20 there were only four days during which tropical storm activity occurred. In September, the switch flipped, and we had four hurricanes (including two majors) in September, and activity continued well into November.
August: 3/0/0 and 10 ACE. Rest of season: 11/9/4 and 96 ACE
This season would end at 16/12/5 and 151 ACE

2003: Featured June and early July activity (including Hurricane Claudette) and another underperforming August—between July 24 and August 27, only one hurricane formed, Erika, lasting a total of three days (and only forming from a non-tropical origin). The switch flipped around August 27, and that year featured Fabian and Isabel.
August 1-27: 1/1/0 and 2 ACE. Rest of season: 11/4/2 and 157 ACE
This season would end at 16/7/3 and 212 ACE

2006: This was an El Nino year, but the atmospheric conditions had not yet set in by August, and (as a result of El Nino developing later than usual) the season was forecast to be more active, had that not occurred, so I’ll compare August and September specifically. August featured three storms and one hurricane, underperforming a bit, but having one more storm than this year. But (despite the by-then developing El Nino) from September 7 until the early season shutdown, still pumped out 4/4/2.
August: 3/1/0 and 10 ACE. September: 4/4/2 and 63 ACE
This year would be at 9/6/3 and 118 ACE with October and November still to come.

2016: While this year is running about a week behind with August activity it’s still a good comparison. Prior to August 22, the season had a Cat 1 in the Caribbean, and a tropical storm in the MDR, This followed a lot of early season activity and a storm-free July. after which Gustav (Cat 3) and Hermine developed, but the season struggled through the first half of September, and then we had three back to back majors at the back of the season, including Matthew.
August 1-20 activity (and including July since this season was displaced earlier) was:
2/1/0 and 8 ACE. Rest of season: 9/5/4 and 126 ACE
This season would end at 14/7/5 and 181 ACE

2017: While we’re behind this year in storm count that’s mostly because that year featured two non-tropical origin storms and this year none, but those were in April and July. August activity matches this year through the middle of the month—a Cat 1 at the start of the month, and Cat 2 around mid-month. We had Harvey come into Texas on Aug 25 and then Irma formed around the 30th, and we all know how the rest of the season went. The key difference is this year does not seem like it’ll feature a Harvey, but like 2016 this year could be offset by a week or so, so I’ll split the month.
Aug 1-16: 7/2/0 and 23 ACE. Rest of season: 10/8/6 and 197 ACE.
This season would end at 15/10/7 and 252 ACE and 240 ACE without Harvey factored in

2018: Possibly the most apt comparison season at this point, despite being an El Nino. Early season activity, two August storms (albeit in the subtropics (El Nino year and all), and a largely dead MDR during August. Then the lid came off in September, and we had Florence and Michael.
August: 2/0/0 and 3 ACE. Rest of season: 10/5/2 and 114 ACE.
This season would end at 15/8/3 and 167 ACE

2022: Throwing this in because we had a storm-free August, and overactive/northward displaced monsoon trough, and still had an active September through November. Another feature in common was the June monsoonal development followed by late June/early July MDR-origin development, and entered August with the same storm count as this year.
August: 0/0/0 and 0 ACE. Rest of season: 10/7/2 and 91 ACE
This season would end at 15/10/3 and 146 ACE


So summing up, if the years progress the same as the given years, we’d end up, sorted lowest to highest ACE, at:
2000: 15/8/3 and 107 ACE.
2006: 9/6/3 and 118 ACE (note: this is only through September 30)
2022: 15/10/3 and 146 ACE
2001: 16/12/5 and 151 ACE
2018: 15/8/3 and 167 ACE
2016: 14/7/5 and 181 ACE
2003: 16/7/3 and 212 ACE
2017: 14/9/6 and 240 ACE

[FireRat]

Very interesting post Hammy!
I remember the Debby debacle funny enough, was warching Wsvn 7 news and Bill Kamal had the storm probably hitting Miami as a 140 mph storm in their cone, surely was quite a threat but of course she ran into Hispaniola!
I have a feeling the 2016 comparison may be the closer one, we might see a Matthew type system with that track even later in September or October, just a hunch.
Next season could be like 2017 if this one takes on a 2016 path, would be the 2nd year after El Niño too.

2024 has already been quite a bizarre season, and after seeing what already happened with Beryl, one needs to pay extra close attention to the tropics this year! Will be interesting to see how this season plays out.

[al78]

2000 was an unusual season in that many storms which formed in the MDR failed to become significant hurricanes. Phil Klotzbach noted this in his post-season summary and attributed the lack of activity to a strong TUTT over the western Atlantic.

https://tropical.colostate.edu/Forecast ... 000-11.pdf