Curious SE Pacific cyclone off Chile (37S 82W)

[TheAustinMan]

Was looking at some full-disk imagery from GOES-16 when I noticed a peculiar cyclone spinning about in the southeastern Pacific off the coast of Chile. It's expected to weaken as it approaches the Chilean coast over the next few days, but for now, it does have some decent organization and convective activity about the center. Cyclone phase analyses have it as an asymmetric shallow warm core system, though it'd be great if a pro met with a better handle on tropical cyclogenesis could interpret this storm; I'm just reading the pretty graphics

143 KB image. Source GOES MSFC.


161 KB image. Source Florida State University cyclone phase evolution.

[AJC3]

Looks like a vertically stacked fall cold core SHEM cyclone that's making a brief run at developing a shallow warm seclusion at its center.

Nice find!

[Ptarmigan]

No tropical cyclone is known to hit the West Coast of South America. The waters off the West Coast of South America are cooler. There is not a lot of land mass, which does not heat the water up unlike the Northern Hemisphere. Point Nemo is the most remote spot on the ocean in the Southeast Pacific. One reason why the Atacama Desert is very dry.

[TheAustinMan]

The hybrid cyclone has weakened somewhat per analyses in the over the past day, but it remains a peculiar and somewhat convectively organized sight in a location that's never seen a designated cyclone, at least in my knowledge (though there may have been an INVEST designation outside the ordinary 90-99 range, but it escapes my memory). Convection has built somewhat in the last few hours.

Source: GOES MSFC. About 290KB per image.



 https://twitter.com/TropicalTidbits/status/993568187068362752

[Sciencerocks]

Wouldn't be totally surprised to see an invest if convection can fire directly over the center. We will see...

[AnnularCane]

Cute little thing.

[hurricanes1234]

[hurricanes1234]

Looks to have more convection this evening than earlier today. Impressive.

[Sciencerocks]

Can anyone argue that this isn't currently a tropical cyclone? I want to hear your case on why I would be wrong to say it is.

[Hammy]

Can anyone argue that this isn't currently a tropical cyclone? I want to hear your case on why I would be wrong to say it is.

Very much looks at least subtropical but I don't know if there's any protocol in place for formally classifying SE Pacific systems at the moment.

[hurricanes1234]

It's subtropical according to this article. No designated tropical cyclone agency to declare it as such though.

https://www.wunderground.com/news/2018-05-08-subtropical-cyclone-chile

[AJC3]

Can anyone argue that this isn't currently a tropical cyclone? I want to hear your case on why I would be wrong to say it is.

I would say at this point, it's certainly no less of a TC than the Angola cyclone IMO. And it's peak intensity is about 10KT stronger.

[1900hurricane]

 https://twitter.com/DRmetwatch/status/994007681320083456

[talkon]

The hybrid cyclone has weakened somewhat per analyses in the over the past day, but it remains a peculiar and somewhat convectively organized sight in a location that's never seen a designated cyclone, at least in my knowledge (though there may have been an INVEST designation outside the ordinary 90-99 range, but it escapes my memory). Convection has built somewhat in the last few hours.

Three years ago there was STC Katie in this general region.

[CrazyC83]

Who is responsible for warning, if anyone, in that area? What basin would it be considered?

I agree re: a TC classification.

[USTropics]

Who is responsible for warning, if anyone, in that area? What basin would it be considered?

I agree re: a TC classification.

There is no official agency that is mandated to provide warnings for this area, as technically it would fall outside of the South Pacific cyclone basin. The Chilean Navy Weather Service (http://meteoarmada.directemar.cl/prontu ... nicio.html) would be responsible for issuing High Sea Warnings if this system were to warrant it. There is a post season reanalysis, as was the case with Subtropical Cyclone Katie, where researchers confirmed it was an established substropical cyclone, but it was not added to the official list of 2014-2015 South Pacific Cyclone Season (it was included in the foot notes as 'other systems').

[BYG Jacob]

Oh my god, its a frickin" unicorn. Enjoy this ladies and gents, you probably NEVER see this happen again.

[Cuda]

Oh my god, its a frickin" unicorn. Enjoy this ladies and gents, you probably NEVER see this happen again.

Is it a unicorn specifically because of where it is located?

[1900hurricane]

Oh my god, its a frickin" unicorn. Enjoy this ladies and gents, you probably NEVER see this happen again.

Is it a unicorn specifically because of where it is located?

Yep, that is exactly the reason.

[CrazyC83]

The fact this is happening in a non-El Nino year is amazing too.

That probably was T3.0 looking at it.