ATL: LARRY - Post-Tropical - Discussion

[Sciencerocks]

[Blown Away]

@8.7N/15.3W

[cycloneye]

 https://twitter.com/cyclonicwx/status/1432445482111012877

[cycloneye]

Wow, just emerged from Africa and look how well organized it is. The convection will help to tighten it and off to the races.

[aspen]

At the rate this is organizing, I won’t be shocked if we have TD12 by tomorrow morning. Maybe we’ll see a seventh named storm before August wraps up.

[cycloneye]

An area of low pressure associated with a tropical wave is located
over the far eastern tropical Atlantic just off the west coast of
Africa. This system is producing disorganized showers and
thunderstorms, mostly on its south side. Environmental conditions
are conducive for development of this system, and a tropical
depression is likely to form within the next couple of days while it
moves west-northwestward at 10 to 15 mph.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...90 percent.

[ouragans]

Invest 90L
As of 00:00 UTC Aug 31, 2021:

Location: 8.5°N 16.3°W
Maximum Winds: 25 kt Gusts: N/A
Minimum Central Pressure: 1007 mb
Environmental Pressure: N/A
Radius of Circulation: N/A
Radius of Maximum wind: 60 nm

[Teban54]

Surely it looks like 2021 isn't facing issues of large, CAG-like waves taking a long time to consolidate, which 2020 had and some users predicted 2021 would have.

[abajan]

Seeing comments hoping it recurves. But if it does so, it may threaten the Azores. In fact, I think that's exactly what a couple runs of the GFS have been showing.

[weeniepatrol]

This season is becoming uncomfortable

[cycloneye]

Seeing comments hoping it recurves. But if it does so, it may threaten the Azores. In fact, I think that's exactly what a couple runs of the GFS have been showing.

Or Bermuda as the European shows. Both areas have to watch this.

[Blown Away]

Invest 90L
As of 00:00 UTC Aug 31, 2021:

Location: 8.5°N 16.3°W
Maximum Winds: 25 kt Gusts: N/A
Minimum Central Pressure: 1007 mb
Environmental Pressure: N/A
Radius of Circulation: N/A
Radius of Maximum wind: 60 nm

.2 Degrees South
1.0 Degree West
Since 18z...

[Teban54]

 https://twitter.com/WxPatel/status/1432489606801510403

[cycloneye]

A. INVEST (90L)

B. 30/2330Z

C. 8.5N

D. 16.7W

E. THREE/MET-11

F. T1.5/1.5

G. IR/EIR/SWIR

H. REMARKS...3/10 BANDING RESULTS IN A DT OF 1.5. MET AND PT=1.5. LLCC
APPEARS TO HAVE REFORMED TO THE W LAST 6 HR. FT IS BASED ON MET DUE
IRREG/PULSING CONVECTIVE PATTERN AND UNCERTAINTY OF EXACT POSITION
OF LLCC.

I. ADDL POSITIONS

NIL


...KONON

[sma10]

I don't believe 90L will be a US or Caribbean threat, but it did get me thinking. Has the US ever been struck by a system that developed East of 20W? I don't ever recall one.

[LarryWx]

I don't believe 90L will be a US or Caribbean threat, but it did get me thinking. Has the US ever been struck by a system that developed East of 20W? I don't ever recall one.

Yes: Hugo of 1989 was the last one I think. Dora of 1964. Able of 1952. #4 of 1947. #6 of 1938. #4 of 1928. #6 of 1893 likely was as well as some others before the satellite era. I'm counting those that were declared a TD+ by 20W. And that can be very subjective, too. Some would argue that Donna of 1960 fits in here, too.

[sma10]

I don't believe 90L will be a US or Caribbean threat, but it did get me thinking. Has the US ever been struck by a system that developed East of 20W? I don't ever recall one.

Yes: Hugo of 1989 was the last one I think. Dora of 1964. Able of 1952. #4 of 1947. #6 of 1938. #4 of 1928. 36 of 1893 likely was as well as some others before the satellite era.

Really cool stuff - and some real doozies in that list. Pretty interesting that it happened last mid-century at a clip of about 1 every 7 years (5 in 36 years). Yet only once in the past 57 years. Weird.

[LarryWx]

I don't believe 90L will be a US or Caribbean threat, but it did get me thinking. Has the US ever been struck by a system that developed East of 20W? I don't ever recall one.

Yes: Hugo of 1989 was the last one I think. Dora of 1964. Able of 1952. #4 of 1947. #6 of 1938. #4 of 1928. 36 of 1893 likely was as well as some others before the satellite era.

Really cool stuff - and some real doozies in that list. Pretty interesting that it happened last mid-century at a clip of about 1 every 7 years (5 in 36 years). Yet only once in the past 57 years. Weird.

Check out my edited post as I added Donna as one that many would also include. I counted a total of ~24 that formed by 20W in the record. If I count just Hugo, Dora, Able, 1947, 1938, and 1928, that's 6 of 24 or 1 in 4 that hit the CONUS.

[Sciencerocks]

[Teban54]

I don't believe 90L will be a US or Caribbean threat, but it did get me thinking. Has the US ever been struck by a system that developed East of 20W? I don't ever recall one.

Here are the easternmost forming tropical cyclones that hit the CONUS as per HURDAT:

- 1928 Okeechobee hurricane: 14.2N, 17.0W as a TD
- Dora 1964: 14.0N, 17.0W as a TD
- Able 1952: 14.6N, 19.0W as a TD
- 1938 New England hurricane: 12.8N, 19.4W as a TD
- Hugo 1989: 13.2N, 20.0W as a TD
- 1947 Fort Lauderdale hurricane: 14.5N, 20.1W as a TD
- 1893 Sea Islands hurricane: 18.1N, 20.2W as a TS (likely a TD before 20W if that TS point is accurate)
- Fran 1996: 14.0N, 21.0W as a TD
- 1933 Chesapeake–Potomac hurricane: 12.3N, 21.5W as a TD
- Donna 1960: 10.2N, 22.8W as a TD
- Gloria 1985: 13.3N, 23.6W as a TD
- Florence 2018: 13.8N, 23.8W as a TD
- 1933 Cuba–Brownsville hurricane: 12.6N, 24.9W as a TD
- Georges 1998: 9.7N, 25.1W as a TD
- Frederic 1979: 11.0N, 25.5W as a TD
- Dennis 1981: 10.5N, 25.7W as a TD (dissipated before reforming and hitting CONUS)
- 1915 Galveston hurricane: 14.0N, 26.0W as a TD
- Irma 2017: 16.1N, 26.9W as a TD
- Ivan 2004: 9.7N, 27.6W as a TD

Note that I would take the pre-satellite and even early satellite ones with a grain of salt, as we would likely have no reliable way back then to distinguish a TD/TS from a vigorous tropical wave, especially as far as a closed circulation is concerned. (We still have that problem today, don't we?)