ATL: INVEST 92L - Discussion

[Jr0d]

I think it would be prudent for the NHC to issue PTC advisories at this point. Clearly a circulation and 92L is approaching Gulf Stream. At most this will be a TD or minimal TS at landfall......MGC

I don't think it's necessary. Why have an advisory for at best a minimal storm over a small area when an afternoon thunderstorm can bring more intense winds?

If this was expected to strengthen up to landfall then sure it would be justified but a mostly naked swirl that appears to be struggling to keep convection firing is really not much of threat, with the exception of marine hazards. Also the rain impact will likely be minimal for a tropical system regardless of it becomes a depression or even storm before landfall.

Issuing unnecessary tropical storm warnings also runs the risk of complacency when less informed folks get minimal weather who are under the advisory and are more likely to ignore future advisories.

[Nuno]

So, center is on the far N edge of the main convection. Is this organized enough to warrant TD status? Opinions?

It's clearly a TD. It's so strange how it isn't at least designated as a *Potential* TC.

Convection isn’t quite organized enough to be designated a TD per NHC.

That isn't something to prevent the designation of a PTC, is it? Whether convection is organized or not, or to what extent, seems subjective from forecaster to forecaster.

Luckily this will be fairly weak at landfall, but I wish the criteria was a bit more clear in their public messaging.

Issuing unnecessary tropical storm warnings also runs the risk of complacency when less informed folks get minimal weather who are under the advisory and are more likely to ignore future advisories.

The opposite is also dangerous. I would never call storm warnings unnecessary if the storms are actually going to produce the effects in the first place. Products exist for a reason. It is dangerous if one were to suddenly escalate and RI. Kind of a worrying omen that we have a system like this is June, and the NHC is going to have to make a lot of difficult decisions this summer.

[NDG]

Lame excuse not to upgrade it to TD2, but they're the experts.

[BobHarlem]

This new convection blob pumped up shortly after they issued the Special TWO.

[ChrisH-UK]

Latest radar from KJAX, looks like its maybe starting to bundle up around a central rotation

[LarryWx]

This new convection blob pumped up shortly after they issued the Special TWO.
https://i.imgur.com/PlWbmRE.png

That new convection is very close to the center, which is now over the Gulf Stream with its 83-84F SSTs.

[REDHurricane]

Come on NHC, I'm not going to pretend like I know more than they do but if this isn't a TD (at minimum) then I have no idea what a TD even is

[MGC]

I think it would be prudent for the NHC to issue PTC advisories at this point. Clearly a circulation and 92L is approaching Gulf Stream. At most this will be a TD or minimal TS at landfall......MGC

I don't think it's necessary. Why have an advisory for at best a minimal storm over a small area when an afternoon thunderstorm can bring more intense winds?

If this was expected to strengthen up to landfall then sure it would be justified but a mostly naked swirl that appears to be struggling to keep convection firing is really not much of threat, with the exception of marine hazards. Also the rain impact will likely be minimal for a tropical system regardless of it becomes a depression or even storm before landfall.

Issuing unnecessary tropical storm warnings also runs the risk of complacency when less informed folks get minimal weather who are under the advisory and are more likely to ignore future advisories.

I've witnessed thunderstorms with over hurricane force winds....should we stop issuing hurricane warning? Yes, this is a marine hazard and PTC advisories could save a life at sea......MGC

[TheAustinMan]

I'm definitely a little surprised by the lack of a TD/TS designation here. Recon was able to locate a well-defined center of circulation and transmitted a vortex data message --- something that's only done if such a center is located --- and 92L received Dvorak classifications this morning of T2.0 from the Tropical Analysis/Forecast Branch and T1.0 from the Satellite Analysis Branch. I would have assumed that the combination of these two factors would be sufficient for some classification, with the recon data justifying the "well-defined center" prong and the Dvorak satellite analysis justifying the "organized convection" prong. The NHC's decision not to initiate at 12Z or 15Z would comport with what I've sensed to be an internal shift away from designating short-fuse systems. That was even a part of my guess in the Storm2k season poll back in early May.

Models in the last two days have really not been able to capture this system in meaningful capacity, and that includes the higher resolution mesoscale models. Mid-level northerlies, which have been modeled, are inducing northerly shear over the system as apparent on satellite imagery. That said, while models do not show much further development, the system is far more organized than any model shows. It is a bit of a gamble by the NHC to not initiate here; it certainly would not be a good look if further intensification/development occurred closer to land. While this may not be a very impactful system, and likely won't be, from a consistency and scientific stewardship perspective it does seem a bit odd that this hasn't gotten the nod, let alone a red marker on the TWO.

Source: AWIPS CAVE

[Sciencerocks]

 https://x.com/WXTriad/status/1804167321050632669

[Sciencerocks]

[Zonacane]

Nice spiral band wrapping in

[Nuno]

It is a bit of a gamble by the NHC to not initiate here; it certainly would not be a good look if further intensification/development occurred closer to land.

You would know more than me, but isn't this the precise type of storm that the PTC designation was created for?

[zhukm29]

Very surprised this hasn’t been designated yet. Certainly looks better that systems that have been designated in the past, and I agree that from a consistency standpoint this should at least get an upgrade to TD2.

[emeraldislenc]

I agree they have upgraded worse looking systems!

[chaser1]

It's clearly a TD. It's so strange how it isn't at least designated as a *Potential* TC.

Convection isn’t quite organized enough to be designated a TD per NHC.

That isn't something to prevent the designation of a PTC, is it? Whether convection is organized or not, or to what extent, seems subjective from forecaster to forecaster.

Luckily this will be fairly weak at landfall, but I wish the criteria was a bit more clear in their public messaging.

Issuing unnecessary tropical storm warnings also runs the risk of complacency when less informed folks get minimal weather who are under the advisory and are more likely to ignore future advisories.

The opposite is also dangerous. I would never call storm warnings unnecessary if the storms are actually going to produce the effects in the first place. Products exist for a reason. It is dangerous if one were to suddenly escalate and RI. Kind of a worrying omen that we have a system like this is June, and the NHC is going to have to make a lot of difficult decisions this summer.

This is a fair and good discussion.

NHC does a great job of projecting risk and protecting the general public in the face of a tropical cyclone risk. I personally think that some past tropical cyclone designations were unnecessary and not fully meeting "all" prerequisite characteristics especially in light of potential conditions like rainfall or storm surge flooding impact, where protecting the public interest was paramount. Having said that, I believe that forecasting itself along with communicating potential risk should be 100% consistent.

Issuing Watches or Warnings now would offer little benefit for giving the general public reasonable time to react. More importantly, I think it would convey a message that forecasters were "caught with there pants down" (which would be altogether wrong). In my opinion, the error might have been not a issuing PTC Watch at least 24 hours ago with the clear communication of risk potential being minimal and primarily associated with high seas and possible coastal impact such as minor coastal flooding and strong gusts in squalls. I was under the impression that Potential Tropical Cyclone alerts or warnings were created for this very reason.... not limited to those events where NHC was pretty sure that a last moment upgrade to tropical storm was likely or imminent.

Thus far the forecasting of 92L has been correct with exception of this small feature appearing to slightly overperform in terms of satellite presentation and better co-located convection. That's saying a lot considering how poorly all models performed.

[kevin]

Please explain it it to me if I an misunderstanding something here. But with many 30+ kt SFMR & surface wind estimates (as well as multiple 35 kt+ measurements) & a clear center with plenty of convection near it, how is this not at the very least a TD? It doesn't matter how long the TC will still have before landfall, a TD designation should not be subjective based on impacts or the presence of prior advisories, but purely on whether a system matches the requirements and as far as I can see this one does. The NHC consists of experts in their field so I'm sure they're making the right call, I just don't fully understand it myself so if anyone could clarify.

[kevin]

53 kt SFMR (uncontaminated measurement) as well as 6 other 35+ kt SFMR measurements and a well-defined center with now at least < 6 kt FL winds. Not sure how they could still argue against an upgrade now.

[Hypercane_Kyle]

53 kt SFMR (uncontaminated measurement) as well as 6 other 35+ kt SFMR measurements and a well-defined center with now at least < 6 kt FL winds. Not sure how they could still argue against an upgrade now.

Flight level winds don't really match up... looks like a gust to me.

[Sciencerocks]

53 kt SFMR (uncontaminated measurement) as well as 6 other 35+ kt SFMR measurements and a well-defined center with now at least < 6 kt FL winds. Not sure how they could still argue against an upgrade now.

As far as I am concern it will be a tropical storm in my archives and in my mind with such data. You can throw me in a prison cell and I won't ever stop saying it was.