ATL: INVEST 94L - Discussion

[Teban54]

Another concern is that even with advanced technology like ASCAT, a lot of the criteria for classifying a TC still leave room for (sometimes great) subjectivity. The three most common topics of debate are probably:

• How well-defined does the LLC have to be? Does a broad or elongated LLC suffice?
• How persistent must the convection be? Can it be pulsing every few hours, as long as the poofing towers are always replaced by new ones soon?
• How close should the convection be to the LLC for it to be considered "associated"? Does it count if the convection is visibly sheared and leaves the LLC exposed, but still clearly firing from the center?

For both 92L and 94L, some of these criteria can be debated. But the problem is that some other systems that had equally debatable answers in the recent past (e.g. Odette 2021) were also classified. Given the large number of TDs in the 1970s and 80s, I bet some of them were debatable, too.

[zhukm29]

94L is also a tiny system, which models do not handle well. Jose was a good example from last year - all the models showed it dissipating so it was dropped to 0/0, and then it formed like a day later

[ouragans]

Up 30/30

East of the Leeward Islands (AL94):
Showers and thunderstorms continue to show signs of organization 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 could 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. Regardless of development, this system could
produce locally heavy rainfall and gusty winds across the northern
Leeward Islands on Friday.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

[chaser1]

I think those on Montserrat or Antigua might benefit from taking in loose patio furniture or small yard items. This little system sure does have staying power LOL. It is pretty small yet I wonder if pseudo water spout conditions might impact a tight small area if/when the center moves directly over?

[zhukm29]

New microwave imagery of 94L:

[Nimbus]

A weak low drifting into the Caribbean then up over Puerto Rico and out to sea?
80% of NOLA already has their power back on but hopefully this one won't be a problem for ConUS.

[floridasun]

will nhc make chance higher at 8pm?

[zhukm29]

 https://twitter.com/mikefischerwx/status/1834276661287866492

[cycloneye]

East of the Leeward Islands (AL94):
Scattered showers and thunderstorms continue in association with a
small area of low pressure located a couple of hundred miles east of
the Leeward Islands. 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. Regardless of development, this system could
produce locally heavy rainfall and gusty winds across the northern
Leeward Islands on Friday.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

[chaser1]

Pulsating convection is on the increase. I'm just wary of tenacious very small systems. It could quickly go "poof" but it hasn't yet. It may be interesting to watch its approach on radar

[Teban54]

[Ubuntwo]

Surface obs and an earlier ASCAT pass suggest this has now opened into a trough. Do we think it will be added in post?

[ChrisH-UK]

94L with 92L in tow south east of it this morning. The models 94L should be moving WNW toward Bahamas bearly registering on the models, the models also show a large area of the Caribbean with little shear and plenty of heat which is a head scratch on why they don't developed it further, may be the small size etc is having a factor.

[zhukm29]

Surface obs and an earlier ASCAT pass suggest this has now opened into a trough. Do we think it will be added in post?

Probably a good candidate if any - using jconsor's analysis I would probably set the formation around Tuesday night and dissipation earlier this morning. Not sure what I would put for max winds since we never got any good ASCAT passes during its peak, but given the tiny size of the system I wouldn't be surprised if winds could have attained minimal TS strength at some point yesterday. We'll see what happens in the post-season.

[cycloneye]

Bye.

Northern Leeward Islands (AL94):
An area of low pressure near the Northern Leeward Islands is
producing limited shower and thunderstorm activity. Environmental
conditions, including the proximity of dry air, do not favor
development of this system and development is no longer expected
while it moves west-northwestward at about 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...near 0 percent.