2021 Indicators: SST's / SAL / MSLP / Shear / Steering / Instability / Sat Images

[Steve]

At least according to the recent GFS run, I sincerely think that a model-not-catching the MJO/CCKW bias may be why the Atlantic does not see anything significant form in the next 16 days; after Pamela, the EPAC falls silent, while the WPAC is somewhat active but does not produce any major typhoons. Yeah, something’s fishy here.

Bet.

[chaser1]

CFS height anomalies in early November, around the time the western basin should be favored for development. This pattern favors a track buried into Central America or recurving through the Greater Antilles.
https://i.imgur.com/Y4vMs1R.png
Very intense upper level winds mean nothing is forming within the Gulf. As soon as SFL gets its first dry season front it will be in the clear. No hints of that (yet) in the models.

Season will likely end following the first cold-front that fully sweeps the Caribbean. I don't see THAT horizon approaching anytime soon. Until then, models will continue to show nada (right up to the point when they suddenly light up like the 4th of July).

[Ubuntwo]

Season will likely end following the first cold-front that fully sweeps the Caribbean. I don't see THAT horizon approaching anytime soon. Until then, models will continue to show nada (right up to the point when they suddenly light up like the 4th of July).

Well put IMO. Models are not depicting the season-ending front just as they are not depicting development. Tropical cyclone formation lead time is generally just a few days. Plenty of waves sneaking across the MDR.

[Category5Kaiju]

CFS height anomalies in early November, around the time the western basin should be favored for development. This pattern favors a track buried into Central America or recurving through the Greater Antilles.
https://i.imgur.com/Y4vMs1R.png
Very intense upper level winds mean nothing is forming within the Gulf. As soon as SFL gets its first dry season front it will be in the clear. No hints of that (yet) in the models.

Season will likely end following the first cold-front that fully sweeps the Caribbean. I don't see THAT horizon approaching anytime soon. Until then, models will continue to show nada (right up to the point when they suddenly light up like the 4th of July).

All the more reason to believe that the models may just be having a hard time understanding that after the favorable CCKW passes the EPAC then it'll likely be the Atlantic that wakes up next. For them to not show the season-ending front but also show no significant activity pick up in the next weeks or so is just bizarre.

[AlphaToOmega]

Big middle finger for those wising for an impact-free October

[boca]

Big middle finger for those wising for an impact-free October

https://i.postimg.cc/v8kDGD8c/21102100-1000.gif

Do you have a link to the site?

[AlphaToOmega]

Big middle finger for those wising for an impact-free October

https://i.postimg.cc/v8kDGD8c/21102100-1000.gif

Do you have a link to the site?

weatheronline.co.uk

[Category5Kaiju]

CFS I will give credit to in the sense that it has consistently shown activity in the Atlantic after mid-month.

[wxman57]

Using the seasonal CFS model for predicting TC development is not advised. Very high wind shear now dominates the Gulf and East U.S. Coast. That shear now includes all of Florida, and it may remain through the next couple of weeks. The only shot at additional development would be in the Caribbean or in the subtropics. This is no 2020...

[Category5Kaiju]

Ok, so here's what I will do: I will post the timelines of all cool neutral/La Nina years since the active era's start in 1995 for easy reference. Getting copious October/November activity is not normal (2020 especially), but seeing a few major hurricanes during that timeframe is pretty typical. The two major exceptions that I see are 2007 and 2010 (2017 if you do not count Ophelia as it was not a W Atlantic storm as well perhaps). We'll see what 2021 does, although my gut is telling me that the CCKW's favorable phase should spark some activity later this month, with a decent chance of seeing something in the WCAR then pretty plausible. If not, then I would be surprised, not going to lie.

1995


1996


1998


1999


2000


2001


2005


2007


2008


2010


2011


2012


2016


2017


2020

[toad strangler]

Using the seasonal CFS model for predicting TC development is not advised. Very high wind shear now dominates the Gulf and East U.S. Coast. That shear now includes all of Florida, and it may remain through the next couple of weeks. The only shot at additional development would be in the Caribbean or in the subtropics. This is no 2020...

A couple a weeks gets us very close to the threshold of no more CONUS 'cane landfalls per climo sans 1985

[AlphaToOmega]

Ok, so here's what I will do: I will post the timelines of all cool neutral/La Nina years since the active era's start in 1995 for easy reference. Getting copious October/November activity is not normal (2020 especially), but seeing a few major hurricanes during that timeframe is pretty typical. The two major exceptions that I see are 2007 and 2010 (2017 if you do not count Ophelia as it was not a W Atlantic storm as well perhaps). We'll see what 2021 does, although my gut is telling me that the CCKW's favorable phase should spark some activity later this month, with a decent chance of seeing something in the WCAR then pretty plausible. If not, then I would be surprised, not going to lie.

1995
https://upload.wikimedia.org/wikipedia/en/timeline/o5mwgk64clkn0nx3ojs1vrhi9pxkfu4.png

1996
https://upload.wikimedia.org/wikipedia/en/timeline/9466c4b5b4756bd8f9d95e75416d7821.png

1998
https://upload.wikimedia.org/wikipedia/en/timeline/3xyvhneu7hmxyc4f52xjn38is10ymmd.png

1999
https://upload.wikimedia.org/wikipedia/en/timeline/70c4220e451c4ba743c542d4ce7f2791.png

2000
https://upload.wikimedia.org/wikipedia/en/timeline/f82aedaca98bef461759f6eb2a0f2c14.png

2001
https://upload.wikimedia.org/wikipedia/en/timeline/i94gc6qz0cn42l21ubvtg9zkuu9fygq.png

2005
https://upload.wikimedia.org/wikipedia/en/timeline/nrdwfc8w8kzpqzdw0rk8k88inxlutma.png

2007
https://upload.wikimedia.org/wikipedia/en/timeline/iis13x5mxnkn0bkpid2e8rmxki367jn.png

2008
https://upload.wikimedia.org/wikipedia/en/timeline/86d1j6u8v5qap56wd1799ueol477d6l.png

2010
https://upload.wikimedia.org/wikipedia/en/timeline/e0b2vkmbrlrjdz5iny3o56v71o5nvi1.png

2011
https://upload.wikimedia.org/wikipedia/en/timeline/5eecd1b32cb9cf9e143ca516fde004dd.png

2012
https://upload.wikimedia.org/wikipedia/en/timeline/b7fu0g5mlk5cv3x53ayzuasb9fvz1ta.png

2016
https://upload.wikimedia.org/wikipedia/en/timeline/7dkigbe4n7spafr8j6tf6i5odpwbxtr.png

2017
https://upload.wikimedia.org/wikipedia/en/timeline/mvwjzaf4ej35o3er04lw403v0bwz5rt.png

2020
https://upload.wikimedia.org/wikipedia/en/timeline/aq63elp2btahkf9mikk4ukb93uzkk1l.png

2012 was warm-neutral during ASO.

[AlphaToOmega]

Don't you love it when models ignore very obvious signals? It always gives me a chuckle.

[WiscoWx02]

Signal appears to be weakening for the MJO passing through the Atlantic. Not surprising at all in my opinion. Sure, almost every hurricane season that had a La Nina developing produced one major in the Caribbean Sea during October or November, but there is always an exception. There may not be one yet, but that doesn't mean one won't show up. In fact, one is almost destined to show up sooner or later based on probability. I think this year will be the exception to two things, that a La Nina almost guarantees a major hurricane later in the season, and all seasons that see a MDR storm by early July will end as hyperactive.

[AlphaToOmega]

Quite a potent -VP signal in this Indian Ocean as well as a -VP cell south of the Caribbean
This seems like this sort of setup screaming for a major hurricane
Climatology is also favoring activity during this month
We do not leave the peak of hurricane season until November 1

[aspen]

Using the seasonal CFS model for predicting TC development is not advised. Very high wind shear now dominates the Gulf and East U.S. Coast. That shear now includes all of Florida, and it may remain through the next couple of weeks. The only shot at additional development would be in the Caribbean or in the subtropics. This is no 2020...

IMO, if anything from the Caribbean does threaten the CONUS, it’ll be more like Eta than Zeta — much weaker than its peak in the WCar and probably just a TS.

[Category5Kaiju]

If for whatever reason this season does not produce any majors going forward (especially in the West Atlantic), then I think we're going to need to do some heavy, extensive, retrospective research and studies on what happened, or what went wrong, or why it turned out to be an "exception." Because clearly you would think that the above average sst anomalies and the past behavior of the season to rumble into action with each favorable CCKW pass would suggest otherwise (not to mention a triple negative, solid -ENSO, -PMM, -PDO phase of the Pacific).

[AlphaToOmega]

This gives me a chuckle

[Category5Kaiju]

 https://twitter.com/WxTca/status/1447220909035638788




Here's this as well..

[LarryWx]

CFS height anomalies in early November, around the time the western basin should be favored for development. This pattern favors a track buried into Central America or recurving through the Greater Antilles.
https://i.imgur.com/Y4vMs1R.png
Very intense upper level winds mean nothing is forming within the Gulf. As soon as SFL gets its first dry season front it will be in the clear. No hints of that (yet) in the models.

Season will likely end following the first cold-front that fully sweeps the Caribbean. I don't see THAT horizon approaching anytime soon. Until then, models will continue to show nada (right up to the point when they suddenly light up like the 4th of July).

All the more reason to believe that the models may just be having a hard time understanding that after the favorable CCKW passes the EPAC then it'll likely be the Atlantic that wakes up next. For them to not show the season-ending front but also show no significant activity pick up in the next weeks or so is just bizarre.

Why does there need to be a “season-ending front” to likely end a season for all practical purposes? From where did this concept originate? Please provide links to credible sources on this idea.

Anyway, there’s a good reason for the models thread to be very quiet. There’s been and still is very limited activity on the two week models/ensembles. This takes us through 10/25, which is past the end of the climo secondary/final peak of the season. Thus, the outlook for future big threats to land masses is improving a good bit from day to day. Not over, but improving, especially for Conus.

Yes, due to global warming, the active part of seasons is likely ending a bit later (and starting a bit earlier) on average. But regardless, once past around 10/21, the threat to even S FL goes down markedly per historical stats. As I posted before, the period 10/17-21 may actually be the highest 5 day threat period of the entire season climo wise to south FL in terms of frequency of TCs being there or very closeby per past seasons. But once just past that period, the threat drops off rapidly leaving only a few outliers.