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

[Zonacane]

For those with issues seeing the Tweet, the CFS cannot be trusted for shear predictions.

[AlphaToOmega]

Wow! Unbelievable back tracking

https://twitter.com/wxpatel/status/1429592439443046403?

The CFS? The model that forecasts below-average shear in the East Pacific despite a La Niña?

[Iceresistance]

I REALLY don't trust the CFS model very much if at all . . . I call it the 'Ultra-Long Range Model'

[SFLcane]

Wow! Unbelievable back tracking

https://twitter.com/wxpatel/status/1429592439443046403?

Isn’t the fact the shear is dropping typical for this time of year as we head into the peak or is there something different here that is causing concern?

It’s a favorable look to the Atlantic no doubt about that now on the stubborn cfs. Its correcting itself on the VP200. Surely we can either have 2010 2.0 or things get further west. It will all come to that z500 steering. The eps as I mentioned has struggled to get any wave past 60w west recently it’s been rather persistent with that. Not much ridging across the central Atlantic it seems. Long way to go so things can change

[aspen]

I just realized there’s been a pattern for all of the seasons of this recent active phase.

In all of the even-number years, the strongest storm is a low-end/borderline/questionable Cat 5 that has had some debate and revision over its true intensity. There was Matthew ‘16 (probably a Cat 4), Michael ‘18 (originally a 4), and both Eta ‘20 (could’ve been a Cat 5) and Iota ‘20 (originally a 5 but got downgraded).

In both of the odd-number years, the strongest storm is a monster of a Cat 5 with some of the highest wind speeds ever seen in the basin and ludicrous SFMR values, but unusually shallow convection for its intensity — Irma ‘17 and Dorian ‘19.

If this oddly specific pattern continues, then 2021, being an odd number year, could see an absolute monstrosity of a storm in the next six weeks. Hopefully this is just a fluke pattern.

[Iceresistance]

I just realized there’s been a pattern for all of the seasons of this recent active phase.

In all of the even-number years, the strongest storm is a low-end/borderline/questionable Cat 5 that has had some debate and revision over its true intensity. There was Matthew ‘16 (probably a Cat 4), Michael ‘18 (originally a 4), and both Eta ‘20 (could’ve been a Cat 5) and Iota ‘20 (originally a 5 but got downgraded).

In both of the odd-number years, the strongest storm is a monster of a Cat 5 with some of the highest wind speeds ever seen in the basin and ludicrous SFMR values, but unusually shallow convection for its intensity — Irma ‘17 and Dorian ‘19.

If this oddly specific pattern continues, then 2021, being an odd number year, could see an absolute monstrosity of a storm in the next six weeks. Hopefully this is just a fluke pattern.

I've noticed it too

Joaquin in 2015 (So close to a CAT 5)
Harvey, Irma, & Maria in 2017 (Triplets of Terror)
Dorian in 2019 (185 mph winds! I've nicknamed this 'The Defying Dorian that will never Die!')

[Iceresistance]

Now, this is Prepare for the ride. Adrian open your eyes. Heck of Kelvin Wave.

https://twitter.com/webberweather/status/1429120573225926660

https://twitter.com/webberweather/status/1429122335320141825

https://twitter.com/dmorris9661/status/1429124562839609345

Can I see the link on where the model GIFs came from?

EDIT: It may need to come from a site that does NOT require a paid Subscription to observe the models . . .

[toad strangler]

I just realized there’s been a pattern for all of the seasons of this recent active phase.

In all of the even-number years, the strongest storm is a low-end/borderline/questionable Cat 5 that has had some debate and revision over its true intensity. There was Matthew ‘16 (probably a Cat 4), Michael ‘18 (originally a 4), and both Eta ‘20 (could’ve been a Cat 5) and Iota ‘20 (originally a 5 but got downgraded).

In both of the odd-number years, the strongest storm is a monster of a Cat 5 with some of the highest wind speeds ever seen in the basin and ludicrous SFMR values, but unusually shallow convection for its intensity — Irma ‘17 and Dorian ‘19.

If this oddly specific pattern continues, then 2021, being an odd number year, could see an absolute monstrosity of a storm in the next six weeks. Hopefully this is just a fluke pattern.

Meh, none of this has anything to do with basin indicators. It's a fun thought but belongs in a place such as the Chinese Zodiac thread

[Shell Mound]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

[Shell Mound]

Wow! Unbelievable back tracking

https://twitter.com/wxpatel/status/1429592439443046403?

Isn’t the fact the shear is dropping typical for this time of year as we head into the peak or is there something different here that is causing concern?

Models underestimated the shear over Henri. Why trust them? They have consistently shown more favourable conditions than have actually ended up verifying, at least insofar as shear and dry air are concerned, especially in the MDR.

[Teban54]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

According to models, Henri, Danny and Bill would not even exist, Fred would have made landfall in Gulf as a remnant low, and Elsa would never have become a hurricane.

[Hammy]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

So far Henri's really the only storm that's underperformed. Several storms that have formed this year weren't even forecast to in the first place.

[toad strangler]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

You expect everything to turn into a Cat 3
There is a reason that historically there are far, far, FAR more tropical storms and depressions than there are hurricanes

[Category5Kaiju]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

Sure, but I am not sure if it would be proper to say that all other storms aside from Grace underperformed. As others mentioned, Bill and Danny formed out of nowhere, Claudette formed at the last minute and even intensified into a TS over land, Elsa became a hurricane in the MDR in early July, Fred came roaring back in the Gulf while not completely dying over Hispaniola never to be seen again, and Ana continued our streak of pre-season May storms. If anything it’s the EPAC that has really underperformed relative to its NS count with many of its storms aside from Felicia or Linda not even forming despite a code red or remaining a weak hurricane (Enrique or Hilda) or tropical storm (Kevin, Jimena, or Guillermo) as not even reaching the potential that the NHC was forecasting. Also I am not 100% sure, but are you talking about “underperform” in the context of ACE or something else? Because quite frankly, with a total ACE of 30 so far in the Atlantic, this is clearly above average for this time of year, and we are even ahead of where 2020 was by this time ACE-wise.

[tolakram]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

Are you trolling? What value does this post add to this thread?

Models underestimated the shear over Henri. Why trust them? They have consistently shown more favourable conditions than have actually ended up verifying, at least insofar as shear and dry air are concerned, especially in the MDR.

I agree, so why trust them when they show no activity?

[Hypercane_Kyle]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

"Other than the borderline Cat 4 making landfall in Mexico and the season's stats being 8-3-1 on August 23, this season is really underperforming thus far"

So far Henri's really the only storm that's underperformed. Several storms that have formed this year weren't even forecast to in the first place.

Henri didn't even underperform. None of the models, including the GFS, caught its genesis.

[Iceresistance]

Well, Henri certainly continued the trend of storms mostly underperforming thus far, Grace notwithstanding.

"Other than the borderline Cat 4 making landfall in Mexico and the season's stats being 8-3-1 on August 23, this season is really underperforming thus far"

So far Henri's really the only storm that's underperformed. Several storms that have formed this year weren't even forecast to in the first place.

Henri didn't even underperform. None of the models, including the GFS, caught its genesis.

What you mean 'Underperforming'? The basin is actually overperforming!

This may be the averages from 1966-2009, but you can clearly see that the Basin is ahead of schedule . . .

Average First Hurricane - August 10th (Elsa became a Hurricane on July 2nd)
Average first Major Hurricane - September 4th (Grace became a Major just before landfall on August 21st)

[cycloneye]

I am repeating this from earlier posts in past few days about ACE. 2021 is overperforming in the ACE thing as after Henri the basin is at 31.7 units and that is above average for this August 23 date. The normal average is 19.3.

[kevin]

I am repeating this from earlier posts in past few days about ACE. 2021 is overperforming in the ACE thing as after Henri the basin is at 31.7 units and that is above average for this August 23 date. The normal average is 19.3.

If 2021 would continue overperforming like this we'd end up with 96.7*(31.7/19.3) = 159 units so just below the hyperactive threshold. 96.7 is the 1951 - 2020 average ACE. So it seems like a an above-average season is very likely and that a hyperactive one is also a possibility.

[Hypercane_Kyle]

What you mean 'Underperforming'? The basin is actually overperforming!

Yes, that's what I said.