ATL: VICTOR - Remnants - Discussion

[CyclonicFury]

This has potential to be a rare October Cape Verde hurricane, even if its intensification window isn't very long.

[cycloneye]

Showers and thunderstorms are showing signs of organization in
association with a tropical wave and broad area of low pressure
located over the far eastern tropical Atlantic. Environmental
conditions are conducive for development, and a tropical depression
is likely to form in a day or two while the disturbance moves
west-northwestward at 10 to 15 mph over the eastern tropical
Atlantic.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...90 percent.

[cycloneye]

As of 12:00 UTC Sep 28, 2021:

Location: 6.7°N 19.7°W
Maximum Winds: 25 kt Gusts: N/A
Minimum Central Pressure: 1010 mb

[cycloneye]

Interesting from Papin.

 https://twitter.com/pppapin/status/1442837120591278084

[Sciencerocks]

[CyclonicFury]

It definitely seems like 90L is becoming the dominant of the two monsoon trough disturbances. 90L is a very large system and it will likely take a day or two for the LLC to become well defined enough for classification. It reminds me of Hurricane Helene from 2018. It has about 3-4 days of low shear, so a hurricane is definitely possible.

[Sciencerocks]

A broad area of low pressure located over the far eastern Atlantic
several hundred miles south-southeast of the Cabo Verde Islands is
producing a large area of showers and thunderstorms. This shower
activity is gradually becoming better organized, and a tropical
depression is expected to form in a day or so while the disturbance
moves west-northwestward at 10 to 15 mph over the eastern tropical
Atlantic.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 5 days...high...90 percent.

[ScottNAtlanta]

It is very far south. Furthest south of any of the invests this season.

[aspen]

90L is gonna be the winner here, it seems. It’s clearly the dominant system and all models have shifted focus onto it.

Based on the GFS and HWRF upper level wind forecasts, 90L/Victor will be in a favorable low-shear environment with acceptable ventilation until Friday afternoon or night. They also have a TC by midday tomorrow. Victor would have about 48-60 hours to intensify and could become a very rare late September eastern MDR hurricane.

[Yellow Evan]

This is basically a Pacific style genesis in the Atlantic which is really fascinating to see.

[grapealcoholic]

90L could reasonably tack on another 20+ ACE if it develops quick like HWRF shows

[Sciencerocks]

[abajan]

Recent satellite-derived surface wind data indicate that the low
pressure system located over the far eastern tropical Atlantic
several hundred miles south of the Cabo Verde Islands is gradually
becoming better defined. The associated showers and thunderstorms
are showing signs of organization, and a tropical depression is
expected to form during the next day or so while the disturbance
moves west-northwestward at 10 to 15 mph over the eastern tropical
Atlantic.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 5 days...high...90 percent.

[cycloneye]

A. TROPICAL DISTURBANCE (90L)

B. 28/2330Z

C. 8.1N

D. 22.7W

E. THREE/MET-11

F. T1.0/1.0

G. IR/EIR/SWIR

H. REMARKS...GREATER THAN 2/10 BANDING RESULTS IN A DT OF 1.0. MET AND
PT=1.0. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...KONON

[cycloneye]

AL, 90, 2021092900, , BEST, 0, 70N, 220W, 10, 1008, LO

[aspen]

Convection is exploding tonight. This might be a TD by the 11am advisory at this rate.

[grapealcoholic]

Convection is exploding tonight. This might be a TD by the 11am advisory at this rate.

5am if we get an ASCAT

[WiscoWx02]

Definitely could make a run at hurricane intensity based off of recent model runs and convective activity. Thing is looking beastly.

[Sciencerocks]

[aspen]

There has been persistent deep convection over where the LLC is likely consolidating for hours now, and the system’s overall structure is improving. This is very close to becoming a TC if it isn’t one already.

Edit: the 8pm TWO says advisories will be initiated if development trends continue. We might have Victor at 11am