NATL: GABRIELLE - Tropical Storm - Discussion

[TampaWxLurker]

From the 11am NHC discussion, emphasis mine:

Atmospheric conditions are expected to remain hostile for a
couple more days, meaning Gabrielle is likely maintain its
current intensity or weaken during that time. It is even possible it could decay into a non-convective post-tropical low for a time.
Assuming it survives, most guidance suggests that the storm will move into more conducive conditions that persist into early next
week, allowing Gabrielle to organize and strengthen as it tracks north to northeastward.

[Ubuntwo]

But Joe is essentially saying that if the no name storm wasn’t called a TC, (even he wasn’t necessarily saying it should have been named…he was kind of wishy-washy on that), why is this naked swirl still being called a TC? In other words, inconsistency/double standard.

Joe’s main objection over the years is that he feels the NHC has a tendency to name or maintain a name for borderline things in the middle of the ocean, but he also feels that they sometimes tend to avoid the same for near-shore systems. Inconsistency is his gripe.

The NHC is very consistent about not naming frontal systems, no matter where they occur. Gabrielle isn't frontal at all. It also wasn't a naked swirl when it was named - that is a more recent development. They typically give about 18 hours operationally after loss of convection before marking a swirl post-tropical.

[TomballEd]

It looks like a post-tropical low already. Unless they count the convection well NE of the center, this is a naked swirl and I thought the rule was organization and convection. This has one but not the other and there would be days of advisories before Bermuda, at least as a PTC if needed.

[MGC]

Remnant low IMO. This is no longer a TC. If convection redevelops then restart advisories.......MGC

[Ubuntwo]

It looks like a post-tropical low already. Unless they count the convection well NE of the center, this is a naked swirl and I thought the rule was organization and convection. This has one but not the other and there would be days of advisories before Bermuda, at least as a PTC if needed.

Generally, those criteria apply for initial designation. The NHC gives two advisories after loss of convection before a system is marked post-tropical on the third. The timing can be tweaked in post.

[REDHurricane]

He was slow this time, but Bastardi finally this morning had his expected say about Gabrielle’s anemic look vs the NC/VA no name system:

What a Joke. Stratocu Swirl Gabrielle

Then Joe compares satellite images of the two.

The issue with the NC/VA low was not its intensity or organization. The issue was that it was a frontal low not a tropical system.

The NHC is very consistent about not naming frontal systems, no matter where they occur. Gabrielle isn't frontal at all. It also wasn't a naked swirl when it was named - that is a more recent development. They typically give about 18 hours operationally after loss of convection before marking a swirl post-tropical.

This raises an interesting question, though: if the impacts (channeling Mark Sudduth) that people experience from a tropical-looking frontal low are functionally identical to an actual tropical storm, then from a weather risk communication perspective (i.e. the reason the NHC exists) why not give the system a name anyway? The entire point of naming systems is to convey to people that a storm is coming and they need to prepare accordingly, so even if it's not 100% meteorologically accurate to designate it as a named tropical storm, I think it would be prudent to give the system a name but with an asterisk so anyone analyzing the season after the fact will know that it didn't technically qualify as a "tropical storm" despite having very similar impacts on people in the affected area. Thoughts?

[cycloneye]

I think we can ruturn to comment about TS Gabrielle, Thank you.

[mitchell]

Joe’s main objection over the years is that he feels the NHC has a tendency to name or maintain a name for borderline things in the middle of the ocean, but he also feels that they sometimes tend to avoid the same for near-shore systems. Inconsistency is his gripe.

I think it gets back to wxman57's comment about broadly serving the public interest, not just following data. The system along OBX was frontal in origin. I think as it moved along the coast near VA Beach it began to acquire subtropical characteristics/appearance but was not intensifying. Reclassifying it as a Tropical Storm and naming it would be widely (mis)interpreted and portrayed in media and social media as an unexpected change or upgrade in intensity, wind and flood risk. People are just SO used to Tropical Storm naming being associated with a newly stronger system, and no amount of concurrent messaging about it just being a change in storm classification, rather than in intensity would mitigate the potential for confusion.

[Teban54]

Even though it's well expected that this would be the weakest point of Gabrielle's life with harshest conditions, I'm still amazed at how bad it is.

[ScottNAtlanta]

The issue with the NC/VA low was not its intensity or organization. The issue was that it was a frontal low not a tropical system.

The NHC is very consistent about not naming frontal systems, no matter where they occur. Gabrielle isn't frontal at all. It also wasn't a naked swirl when it was named - that is a more recent development. They typically give about 18 hours operationally after loss of convection before marking a swirl post-tropical.

This raises an interesting question, though: if the impacts (channeling Mark Sudduth) that people experience from a tropical-looking frontal low are functionally identical to an actual tropical storm, then from a weather risk communication perspective (i.e. the reason the NHC exists) why not give the system a name anyway? The entire point of naming systems is to convey to people that a storm is coming and they need to prepare accordingly, so even if it's not 100% meteorologically accurate to designate it as a named tropical storm, I think it would be prudent to give the system a name but with an asterisk so anyone analyzing the season after the fact will know that it didn't technically qualify as a "tropical storm" despite having very similar impacts on people in the affected area. Thoughts?

I think that is what Gale Warnings are for

[ScottNAtlanta]

It looks pretty dead to me. I've very rarely seen storms that are this void of convection come back. It is possible, just not likely historically speaking

[LarryWx]

I think we can ruturn to comment about TS Gabrielle, Thank you.

Well, Luis, with it now a naked swirl, it no longer looks like a TS. I think most (and I assume you) agree on that.

As some others have said though, the model consensus has for at least a couple of days been suggesting it might weaken or at least struggle til a few days from now. So, this isn’t a total shock. We’ll have to see if the admittedly still well organized tight swirl will maintain itself until convection returns. They often spin down.

[zzzh]

[MEANINGLESS_NUMBERS]

Even though it's well expected that this would be the weakest point of Gabrielle's life with harshest conditions, I'm still amazed at how bad it is.

https://i.postimg.cc/tRsx4qfG/goes19-truecolor-07-L-202509181325.gif

Definitely does not look tropical here.

[wxman57]

I think we can ruturn to comment about TS Gabrielle, Thank you.

Agree. This topic would be best placed in its own thread and out of the Gabrielle discussion.

[chaser1]

But Joe is essentially saying that if the no name storm wasn’t called a TC, (even he wasn’t necessarily saying it should have been named…he was kind of wishy-washy on that), why is this naked swirl still being called a TC? In other words, inconsistency/double standard.

Joe’s main objection over the years is that he feels the NHC has a tendency to name or maintain a name for borderline things in the middle of the ocean, but he also feels that they sometimes tend to avoid the same for near-shore systems. Inconsistency is his gripe.

The NHC is very consistent about not naming frontal systems, no matter where they occur. Gabrielle isn't frontal at all. It also wasn't a naked swirl when it was named - that is a more recent development. They typically give about 18 hours operationally after loss of convection before marking a swirl post-tropical.

NHC does (understandably) give about 18 hr's operationally after loss of convection before downgrading a tropical cyclone following transition to a naked swirl.

Joe is correct regarding an inconsistency in how tropical cyclones are newly designated, especially as it relates to:
1) distance from land
2) model confidence (intensification)

Gale-brielle was upgraded at 5:00 a.m. on September 17, prior to visible satellite and prior to a reasonable period of time in which substantial convection had persistedaround a defined LLC.

The initial Cyclone Discussion states:
"....and although it was not well defined at the time of the
pass, the system was only lacking some northerly winds on its west side. Since deep convection has been persisting and consolidating near the center, it appears to now meet the convective and circulation criteria needed to be considered a tropical cyclone. However, it should be noted that the system is quite large and there is still considerable north-south elongation in the low-level structure.....".

I contend that a combination of dry air and upper level winds significantly disrupted the disturbance during that day, evening, and following day, to an extent that Tropical Storm designation criteria had not been met. One scientific argument suggests that any upgrade is warranted "the moment" that adequate data can arguably support that, in spite of waning or diurnal convective cycles. That's totally fine, as long as that some criteria is applied for all tropical cyclones regardless of time of year or geographic location. The latter has absolutely not been the case.

[MGC]

Gabrielle is completely engulfed by dry air. What little convection that develops is quickly sheared away. Gabrielle's future is perilous at best. I think it will open into a trough in the next couple of days as I don't see the hostile environment Gabrielle is embedded in should persist longer than Gabrielle.......MGC