ATL: INVEST 94L - Discussion

[Subtrop]

AL, 94, 2024091112, , BEST, 0, 152N, 530W, 30, 1010, LO, 34, NEQ, 0, 0, 0, 0, 1012, 60, 10, 0, 0, L, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 022, SPAWNINVEST, al742024 to al942024,

https://ftp.nhc.noaa.gov/atcf/btk/bal942024.dat

[TampaWxLurker]

Which one is this?

We go from nothing to suddenly having more invests than I can keep track of.

[REDHurricane]

Which one is this?

We go from nothing to suddenly having more invests than I can keep track of.

93L is the red one, 92L is the one to the left, and 94L is the one to the left of that

[Teban54]

[Emmett_Brown]

This thing is small, weak and sheared, but it clearly has an LLC

[xironman]

Looks like a mini TD

[xironman]

Continues to fire even though it is in a desert, I am sure that's why the models kill it off. Shear is fairly low so there isn't the best mechanism to force it into the system, if it continues fire eventually it will reach better conditions

[jconsor]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

[Hammy]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

This is such a bizarre change given how many short-lived storms have been added in the reanalysis project, and now many of those likely wouldn't be included by those standards.

[xironman]

8am a bit better

2. East of the Leeward Islands (AL94):
Showers and thunderstorms have become a bit more concentrated in
association with a small area of low pressure located a few hundred
miles east of the Leeward Islands. However, the proximity of dry
air near the system is expected to limit additional development
over the next couple of days. Environmental conditions are expected
to become even less conducive over the weekend while the system
moves slowly west-northwestward.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 7 days...low...20 percent

[HurricaneEnzo]

Gordon, is that you?

Sent from my Pixel 8 Pro using Tapatalk

[Cachondo23]

Continues to fire even though it is in a desert, I am sure that's why the models kill it off. Shear is fairly low so there isn't the best mechanism to force it into the system, if it continues fire eventually it will reach better conditions

https://i.imgur.com/0HlZF50.gif

I don’t understand how do we have a “desert” in the MDR in peak season…

[ChrisH-UK]

94L (left side) is looking much better as it approaches the Winward isles with a weaker looking 92L (right side) in tow. Looks like the dry air around them will stumpt their development.

Source - https://col.st/ZDuai

[zhukm29]

I think this is a TC... a very tiny one though, so I'm not sure if the models can resolve this well. Getting ASCAT to hit this will definitely be a tall task, but we know this has a well-defined LLC, and I wouldn't be surprised if there are TS winds due to its extremely small size.

[ouragans]

Best Track Position and Intensity as of: Thursday, Sep. 12, 2024 12:00 Z

Wind (1 min. avg.): 30 knots (35 mph | 15 m/s | 56 km/h)

Pressure: 1010 mb (29.83 inHg | 1010 hPa)

Location at the time: 274 statute miles (440 km) to the NE (45°) from Bridgetown, Barbados.

Coordinates: 15.9N 56.7W

[ElectricStorm]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

If that change is policy is true then I highly disagree with that. I mean a TC is a TC regardless of how long it last and while sure, it may be a short one that never threatens land but it should be counted as a TC if it is one. To me not counting these would mess up the historical record from a data/science standpoint.

[tolakram]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

If that change is policy is true then I highly disagree with that. I mean a TC is a TC regardless of how long it last and while sure, it may be a short one that never threatens land but it should be counted as a TC if it is one. To me not counting these would mess up the historical record from a data/science standpoint.

It already has as these were not counted for years and not even seen prior to satellites. I favor not naming them during the season and IF one of these shorties happens to have existed longer than expected then it goes into the count post season. I'm still not convinced a count of swirls has any scientific value. Strength (ACE) does, and impacts are what we should be most concerned with.

[Nuno]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

This is such a bizarre change given how many short-lived storms have been added in the reanalysis project, and now many of those likely wouldn't be included by those standards.

I hope they properly upgrade such systems post-season if this indeed is the philosophy now. Doesn't make sense to take such a stance when we have the technology to identify systems no matter how short-lived.

[Ubuntwo]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

If that change is policy is true then I highly disagree with that. I mean a TC is a TC regardless of how long it last and while sure, it may be a short one that never threatens land but it should be counted as a TC if it is one. To me not counting these would mess up the historical record from a data/science standpoint.

It already has as these were not counted for years and not even seen prior to satellites. I favor not naming them during the season and IF one of these shorties happens to have existed longer than expected then it goes into the count post season. I'm still not convinced a count of swirls has any scientific value. Strength (ACE) does, and impacts are what we should be most concerned with.

But they have been getting designated for the past twenty years, if not longer. Look at the 70s/80s seasons and you will find dozens of short-lived MDR TDs just like 92L and 94L, except now we have scatterometer data to confirm closed circulations so the standard is even more rigorous. A reliable record was starting to be built. This introduces another point of inconsistency. What defines a TC? 94L has had a closed circulation and central convection for well over a day now. Would that need to persist for three days, so as to not be a ‘shortie’? IMO, it is no coincidence that a whopping 2/3rds of the official named storms this season have been hurricanes.

[zhukm29]

I am fairly confident 94L will be upgraded to a TS post season. Since the new NHC director took over in 2023, and possibly as early as 2022, there has been a change in policy at NHC to be more strict about naming "shorties" (short-lived TCs, that are expected to last less than 48 hours) that are out at sea and will not have any significant impact on land. I have seen this change discussed by those with inside info who work at organizations connected with NHC, like Andy Hazelton.

94L has likely had a closed circulation since Mon, and since late Tue has had enough persistent deep convection to be classified as a TC.

https://x.com/yconsor/status/1834174781828084159

If that change is policy is true then I highly disagree with that. I mean a TC is a TC regardless of how long it last and while sure, it may be a short one that never threatens land but it should be counted as a TC if it is one. To me not counting these would mess up the historical record from a data/science standpoint.

It already has as these were not counted for years and not even seen prior to satellites. I favor not naming them during the season and IF one of these shorties happens to have existed longer than expected then it goes into the count post season. I'm still not convinced a count of swirls has any scientific value. Strength (ACE) does, and impacts are what we should be most concerned with.

While I agree a lot of tropical storms were likely missed in the pre-satellite era, we do have the tools now to identify these systems, and if they meet the criteria then I don’t see why they can’t be designated if they are going to be added during the post season anyway. We have 42 names to use and I personally think it’s better to designate if a TC meets the criteria since it makes it easier to compare with recent seasons, since this was never an issue until now (vs having a bunch of unnamed tropical storms every season, e.g. where in the alphabet are we now vs other years). Also definitely doesn’t hurt to give the later alphabet names a bit more representation

Personally I think we should use advancements in technology to our benefit when it comes to identifying TCs - as Hammy mentioned, a lot of time has gone into reanalysis projects to identify TCs that were missed before we had all these resources at our disposal, so it just feels a bit counterintuitive to me if we are going to start missing them intentionally. There is no harm in designating if something meets the criteria, and ACE and impacts would still be able to be measured. But that’s just my opinion on things.