ATL: INVEST 94L - Discussion

[Hammy]

Now down to 10/40

What's actually happening with this invest?

It went all the way to 80%, then down to 50%, then back up to 70%, and now back down again to 40%.

I know but I'm talking about why chances arare dropping when there is no dry air, no wind shear, bathwater ssts....

Seems like the sinking air is back--most of the models indicated the more longer-term favorable conditions not arriving until mid-September, but having a favorable Kelvin wave passing through at the end of August/beginning of September (which led to the spurt of activity we had, as well as aiding in Dorian's initial formation)

[DioBrando]

It went all the way to 80%, then down to 50%, then back up to 70%, and now back down again to 40%.

I know but I'm talking about why chances arare dropping when there is no dry air, no wind shear, bathwater ssts....

Seems like the sinking air is back--most of the models indicated the more longer-term favorable conditions not arriving until mid-September, but having a favorable Kelvin wave passing through at the end of August/beginning of September (which led to the spurt of activity we had, as well as aiding in Dorian's initial formation)

Thought it was a suppressed cckw but seems feasible
Am legit thinking humberto can strengthen come the favourable cckw

[Hammy]

I know but I'm talking about why chances arare dropping when there is no dry air, no wind shear, bathwater ssts....

Seems like the sinking air is back--most of the models indicated the more longer-term favorable conditions not arriving until mid-September, but having a favorable Kelvin wave passing through at the end of August/beginning of September (which led to the spurt of activity we had, as well as aiding in Dorian's initial formation)

Thought it was a suppressed cckw but seems feasible
Am legit thinking humberto can strengthen come the favourable cckw

That could be what's responsible for the suppressed phase between now and mid-September--I don't particularly remember the charts much but remember it coming up in discussion.

[aperson]

Yeah, over from models thread I saw this when trying to find any reason at all to be bearish since models weren't heavy on cyclogenesis:

Bearish velocity potential (MJO-related) maybe?

Guess I'll give this more credence in the future.

[ScottNAtlanta]

Yeah, over from models thread I saw this when trying to find any reason at all to be bearish since models weren't heavy on cyclogenesis:

Bearish velocity potential (MJO-related) maybe?

https://i.imgur.com/AwuciTc.png

Guess I'll give this more credence in the future.

Actually...the MJO is headed to the Nul phase...so it really isnt a player in this

[aperson]

Actually...the MJO is headed to the Nul phase...so it really isnt a player in this

First, it's been in Phase 5 over the past two days which is the period where some of us have been surprised that cyclogenesis has not occurred:


Second. The VP200 anomalies in the original figure show sinking in the MDR consistent with Phase 5 over the past two days and may even be enhanced past what one would normally expect on a statistically average weak phase 5. MJO phase space plots do not fully describe the VP anomalies in a local region.

[Aric Dunn]

Looks like on sat we have a smaller more defined circ starting to come together with that recent convective burst in the middle of the broad rotation..

Things may be happening just a tad faster .. lol

[StruThiO]

Things may be happening just a tad faster .. lol

Yeah I suppose you could say that

[hurricaneCW]

Don't sleep on this disturbance especially during peak season.

I suspect we'll be singing a different tune 7-10 days from now. In addition, any wave that develops off of Africa is very likely to get near the US as they'll be a massive eastern ridge in place for the rest of September.

Very ominous steering pattern.

[GCANE]

Slicing thru SAL like a hot knife thru butter

[cycloneye]

No change.

A broad area of low pressure associated with a tropical wave
continues to produce disorganized showers and thunderstorms
several hundred miles west of the Cabo Verde Islands. Some slow
development of this system is possible during the next several days
while the low moves westward across the central tropical Atlantic
Ocean.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...40 percent.

[hipshot]

Yeah, over from models thread I saw this when trying to find any reason at all to be bearish since models weren't heavy on cyclogenesis:

Bearish velocity potential (MJO-related) maybe?

https://i.imgur.com/AwuciTc.png

Guess I'll give this more credence in the future.

How is the MJO different from CCKW's or is one a subset of the other?

[GeneratorPower]

94L looking better this morning with convection consolidating a little bit and the one curved band showing some more activity. Could be this wave that develops.

[Aric Dunn]

Moving right along. I suspect if convection maintians throughout the day we see the chances go up again.

Well that and if convection maintians that long then we will see a much more defined circ as well .

[Abdullah]

Pressure has dropped to 1011 millibars from 1012(while the environmental pressure has stayed constant at 1014) and wind speeds have risen from 20 knots to 25 knots since yesterday. It really doesn't look too shabby right now.

[NDG]

ASCAT this morning though it only showed the eastern portion of 94L is enough evidence that circulation at the surface is broad, the defined vorticity remains above the surface, IMO.
If it keeps tracking to the WSW I think it will have a better chance of developing but closer to the 50th latitude. SAL forecast shows that dust will will not go past the 45th longitude over the next few days.

[DioBrando]

Am legit thinking this is gonna obtain the name Imelda at this point as it's taking way too long to develop, not to mention another wave coming off Africa which might be named quicker.

[GeneratorPower]

ECMWF and GFS both showing activity in the next 240 hours but I would be surprised if they are handling genesis well. Dorian’s genesis was poorly forecasted and I think that will continue. Model changes? Subsidence? Not sure if the cause.

[cycloneye]

A broad area of low pressure and an associated tropical wave are
producing showers and thunderstorms several hundred miles west of
the Cabo Verde Islands. Some slow development of this system is
possible during the next several days while the low moves westward
across the central tropical Atlantic Ocean.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...medium...40 percent.

[abajan]

Now down to 10/40

What's actually happening with this invest?

It went all the way to 80%, then down to 50%, then back up to 70%, and now back down again to 40%.

Did the formation chance actually ever get as high as 80%, though? I've been checking the TWO archives and haven't seen anything higher than 70%. Is it possible the 80% chance was in relation to the system that eventually became Gabrielle?