ATL: GORDON - Remnants - Discussion

[wxman57]

Looks like a short-lived weak system.

[Teban54]

So we can basically throw the latest model runs for this out of the window since it's already a TD? This one has me intrigued, now clue what will happen now.

Euro is probably the closest at depicting this out of any model. If it's right, the system should weaken through central Atlantic, before intensifying near 50W right when it gets picked up by a trough. Since TD7 already has a well-defined center, this scenario holds much more water than GFS's solution that keeps it strung out until or even after the recurve.

[ElectricStorm]

First forecast has 45kts for almost the entire period

[Category5Kaiju]

Cyclogenesis in 2024's eastern MDR that's plagued with dry, stable air? Impossible!

All that talk was merely two weeks ago. Things change very quickly in the tropics, that’s a rule of thumb.

[MarioProtVI]

Looks like a short-lived weak system.

Forecast cone says different to that “short-lived” notion

[tolakram]

A tiny little swirl in the MDR that might amount to something more in a week? They have better tools so we'll have to watch and see. I am disrespecting SEVEN right now.

[AJC3]

A tony little swirl in the MDR that might amount to something more in a week? They have better tools so we'll have to watch and see. I am disrespecting SEVEN right now.

I can assure you, I'm nowhere near the MDR right now.

[tolakram]

A tony little swirl in the MDR that might amount to something more in a week? They have better tools so we'll have to watch and see. I am disrespecting SEVEN right now.

I can assure you, I'm nowhere near the MDR right now.

Awesome typo. lol

[Hurricane2022]

I think our friend GCANE has done a good job in the Hurricane Francine thread, explaining what happens externally and internally in the system and helping us understand what could happen in the future in a good way. So I would like to know what his opinions and analysis are on the future of TD 07L (soon-to-be-Gordon).

[Teban54]

First forecast has 45kts for almost the entire period

That's reminiscent of Philippe 2023, the eternal 45 kt TS (at least operationally). The difference is that Philippe underperformed forecasts at several points of its life, but TD 7 already outperformed the models so far by forming further east than expected (or at all). Unlike Philippe, TD 7 still has a chance to strengthen further west beyond the end of the current forecast.

-----------------------------

Meanwhile... Do the bolded parts of the first advisory imply that NHC is considering the possibility where TD 7 never gets picked up by the trough? That scenario has little to no model support at the moment (not even from ensembles aside from one random GFS run); but to be fair, models did a poor job in forecasting genesis in the first place.

The depression is estimated to be moving 285/16 kt. The system
should move to the west or west-northwest over the next few days
with the storm being steered by a subtropical ridge to the north of
the Azores. Confidence in the depression's track gradually lessens
beyond forecast hour 72 as the synoptic scale flow becomes more
complex. The depression will probably gradually slow down between
hours 72-120 as it becomes caught between a pair of upper level
ridges; one north of the Azores and another north of the Lesser
Antilles. Meanwhile, an amplifying upper trough in the North
Atlantic will attempt to deepen far enough south to steer the
depression northward. How much the upper trough digs southward
will determine if and when the storm takes on a more northerly
track, or if it remains at a lower latitude longer. The forecast
was placed just south of consensus this forecast period.

Wind shear is not expected to be a big hindrance in its
development initially while SSTs along its forecast path will
generally be around 27C. Thus gradually intensification is shown
for the first couple of days. However, shear is forecast to
increase thereafter along with more marginal dry air conditions.
This forecast leans more heavily on the regional hurricane models
which show more modest intensification than the statistical
dynamical tools but could be conservative at the end depending on
how much latitude the system gains.

[Kazmit]

The GFS and Euro both bring this to hurricane strength 8 days from now, potentially threatening the Azores on the recurve. The Euro had it reaching 939mb a few runs ago which would be something else. Too early to tell for now.

[WaveBreaking]

This is probably one of the nicest looking tropical depressions I’ve seen in a while. I always liked how East Atlantic TCs often have a tail of monsoonal flow from the SW along with some stratocumulus to the N. Like when Irma or Helene first got designated.

[MetroMike]

The latest IR shows the cold tops completely collapsing and looks sheared out.
Perhaps a temp disruption.

[Category5Kaiju]

First forecast has 45kts for almost the entire period

That's reminiscent of Philippe 2023, the eternal 45 kt TS (at least operationally). The difference is that Philippe underperformed forecasts at several points of its life, but TD 7 already outperformed the models so far by forming further east than expected (or at all). Unlike Philippe, TD 7 still has a chance to strengthen further west beyond the end of the current forecast.

-----------------------------

Meanwhile... Do the bolded parts of the first advisory imply that NHC is considering the possibility where TD 7 never gets picked up by the trough? That scenario has little to no model support at the moment (not even from ensembles aside from one random GFS run); but to be fair, models did a poor job in forecasting genesis in the first place.

The depression is estimated to be moving 285/16 kt. The system
should move to the west or west-northwest over the next few days
with the storm being steered by a subtropical ridge to the north of
the Azores. Confidence in the depression's track gradually lessens
beyond forecast hour 72 as the synoptic scale flow becomes more
complex. The depression will probably gradually slow down between
hours 72-120 as it becomes caught between a pair of upper level
ridges; one north of the Azores and another north of the Lesser
Antilles. Meanwhile, an amplifying upper trough in the North
Atlantic will attempt to deepen far enough south to steer the
depression northward. How much the upper trough digs southward
will determine if and when the storm takes on a more northerly
track, or if it remains at a lower latitude longer. The forecast
was placed just south of consensus this forecast period.

Wind shear is not expected to be a big hindrance in its
development initially while SSTs along its forecast path will
generally be around 27C. Thus gradually intensification is shown
for the first couple of days. However, shear is forecast to
increase thereafter along with more marginal dry air conditions.
This forecast leans more heavily on the regional hurricane models
which show more modest intensification than the statistical
dynamical tools but could be conservative at the end depending on
how much latitude the system gains.

I’ve been wondering the same; while models seem to suggest this will recurve easily, I do recall some isolated recent runs (like on the Euro, GFS, and CMC) where a ridge seems to build over the system and makes it move very slowly in the Central Atlantic. Who knows?

[Hurricane Mike]

This one will be around for a while. I doubt it gets close to land, but we shall see.

[GCANE]

I think our friend GCANE has done a good job in the Hurricane Francine thread, explaining what happens externally and internally in the system and helping us understand what could happen in the future in a good way. So I would like to know what his opinions and analysis are on the future of TD 07L (soon-to-be-Gordon).

Thanks so much for the compliment 2022.
I will try to look at this tomorrow.
Initial thoughts are that it's got a long way to go.
It is in the peak of the season where protected pouches make it across the MDR.

[cycloneye]

No TS Gordon yet at 18z best track.

AL, 07, 2024091118, , BEST, 0, 160N, 296W, 30, 1007, TD

[MEANINGLESS_NUMBERS]

This is probably one of the nicest looking tropical depressions I’ve seen in a while. I always liked how East Atlantic TCs often have a tail of monsoonal flow from the SW along with some stratocumulus to the N. Like when Irma or Helene first got designated.

https://i.imgur.com/YuiGw6O.gif

It gives the illusion of the banding you might see with a much stronger system. Really cool.

[weeniepatrol]

Looks like a short-lived weak system.

I'm fluent in 57-ese. This translates to "long-tracker that will prevent me from taking days off"

kidding, of course

[Teban54]

The latest IR shows the cold tops completely collapsing and looks sheared out.
Perhaps a temp disruption.

A new burst of convection started immediately after this comment. This should help it get to TS.