ATL: FLORENCE - Post-Tropical - Discussion

[1900hurricane]

It appears the disturbance in the AEJ has been declared Invest 90L.

90L INVEST 180830 0600 12.9N 17.0W ATL 20 1007

(Thread for guidance is here.)

[1900hurricane]

Here is the corresponding IR image.

[Hammy]

Doesn't look like it'll take very long to develop given current organization.

[plasticup]

GFS runs are consistently showing a 930 mb (Cat 4) monster. Euro barely picks it up. Global setup looks good to me. This invest is the one to watch.

So far all steering has this thing recurving around 42-47W, which would make it a solid fish. Still a long way out though.

[GCANE]

A couple hot towers fired off at sunrise.

[GCANE]

Impressive.
Didn't take long for those towers to get a spin started.
Likely got a relatively deep warm core.

https://www.tropicaltidbits.com/sat/sat ... roduct=vis

[plasticup]

Really kicking off this morning. 90L wastes no time. Deep convection, rotation, honestly it looks like a TS this morning. CV better watch out.

[cycloneye]

80%/90%

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Thu Aug 30 2018

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Satellite images and surface observations indicate that a
well-defined low pressure system is located just off the west coast
of Senegal, Africa. Environmental conditions are favorable for a
tropical depression or a tropical storm to form as the disturbance
moves westward or west-northwestward at about 15 mph near the Cabo
Verde Islands during the next day or two. This system is expected to
bring heavy rains and strong gusty winds to the Cabo Verde Islands
on Friday and Saturday, and if the current development trend
continues, Tropical Storm Watches or Warnings will likely be
required for these islands later today. Interests on the Cabo
Verde Islands should continue to closely monitor the progress of
this developing disturbance.

* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...90 percent.

$$
Forecaster Avila

[Ntxw]

Very impressive looking this morning

[plasticup]

80%/90%? Looks like it's already there, to me. At this rate we'll have an upgrade at noon.

[GCANE]

I think that's only the second time I have seen a TC spin up this quickly off the coast.

[GCANE]

Typical TD signature

[Kazmit]

Looks like the GFS may be right with how quickly this develops right off the coast. I think this will be the first major of the season.

[cycloneye]

I think that's only the second time I have seen a TC spin up this quickly off the coast.

When was the first time you saw this rapid development scenario take place?

[Ntxw]

I think that's only the second time I have seen a TC spin up this quickly off the coast.

When was the first time you saw this rapid development scenario take place?

Hurricane Fred in 2015 did I believe. Effected Cabo Verde as a hurricane.

[GCANE]

I think that's only the second time I have seen a TC spin up this quickly off the coast.

When was the first time you saw this rapid development scenario take place?

I can't remember the exact storm or year.
It was the only time I recall when an Invest was declared over land.

[tolakram]

SLIDER: http://rammb-slider.cira.colostate.edu/?sat=goes-16&sec=full_disk&x=20228.5&y=8277&z=5&im=12&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&p%5B0%5D=1&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&s=rammb-slider

Someone needs to call out the 'eye like' feature.

[GCANE]

More data coming in.

[gatorcane]

While a recurving fish looks likely, the latest GFS and CMC ensembles cast a little doubt even if it is slight. See models thread.

[cycloneye]

12z Best Track:

AL, 90, 2018083012, , BEST, 0, 128N, 179W, 25, 1007, LO