ATL: PAULETTE - Remnants - Discussion

[curtadams]

GFS, CMC, and UKMET all agree this still has a deep warm core: http://moe.met.fsu.edu/cyclonephase/ (cyclone 1 on all three), just asymmetric, so this should be sub-tropical, not post-tropical.

[AJC3]

GFS, CMC, and UKMET all agree this still has a deep warm core: http://moe.met.fsu.edu/cyclonephase/ (cyclone 1 on all three), just asymmetric, so this should be sub-tropical, not post-tropical.

It's extratropical. It has become a frontal cyclone, so there's no way it can be classified as an STC. Additionally, the convection is now primarily jet forced. The fact that it has a developing baroclinic leaf on it's northern side, (apparent on satellite) is a dead giveaway. I suspect the phase space diagrams are mistaking "warm core" for "warm sector". An argument could be made that's in a the final transient stage of XTC transition - i.e. a frontal hybrid with a remnant, strongly displaced warm "core" that is almost warm sector. However, the fact that it is well embedded in a baroclinic (frontal) zone, by definition, eliminates this from consideration as being classified as an STC.

[curtadams]

NOAA's surface analysis shows Paulette separate from the front:
High clouds to -60 near the center only is also very atypical for non-tropical systems.

[CrazyC83]

I agree that Paulette is ET right now. However, it is only marginally so and these are the storms that can transition back to (sub)tropical easily. I'd have the probabilities of regenesis right now as 40/50.

[AJC3]

NOAA's surface analysis shows Paulette separate from the front: https://i.imgur.com/BDxwYzZ.gif
High clouds to -60 near the center only is also very atypical for non-tropical systems.

This isn't the case for multiple reasons.

(1) Cold cloud tops associated with a baroclinic leaf in XTCs more often than not, easily reach those temperatures, being at jet stream level

(2) The 12Z Unified Surface Analysis, which was issued 3 hours before Paulette was declared a PTC, showed the fronts barely separated from the cyclone.



The 18Z USA clearly shows the cyclone is frontal.


(Also, the graphic you have attached to your post is from 2005)


On the the satellite image from 15Z (when Paulette was declared a PTC), you can clearly see that the structure of the cyclone on satellite is not that of a STC. Both the the developing baroclinic leaf on its north flank, and the warm and cold fronts to it south and east are apparent. Additionally, widespread cold air stratocumulus is being drawn into the system. Clearly the deep layer environment is baroclinic, not barotropic. This is about as textbook as you can get for a post-tropical cyclone that has recently completed XT transition...

[Hammy]

What affect is all that smoke going to have on intensity and possibly inhibiting redevelopment?

[Blinhart]

:uarrow: What affect is all that smoke going to have on intensity and possibly inhibiting redevelopment?

One of many questions that have to be figured out with this awkward season.

[Kazmit]

Most symmetrical storm of the season?

[Blinhart]

Most symmetrical storm of the season?

https://upload.wikimedia.org/wikipedia/commons/thumb/4/49/Paulette_2020-09-14_Suomi_NPP.jpg/1280px-Paulette_2020-09-14_Suomi_NPP.jpg

So how big can she get? And if that is a current picture, how is she Post-tropical, she still looks tropical to me.

[Kazmit]

Most symmetrical storm of the season?

https://upload.wikimedia.org/wikipedia/commons/thumb/4/49/Paulette_2020-09-14_Suomi_NPP.jpg/1280px-Paulette_2020-09-14_Suomi_NPP.jpg

So how big can she get? And if that is a current picture, how is she Post-tropical, she still looks tropical to me.

That was from a couple days ago.

[CrazyC83]

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

My BT analysis for Paulette:

AL172020, PAULETTE, 47,
20200906, 0000, , LO, 18.2N, 35.3W, 30, 1008,
20200906, 0600, , LO, 18.0N, 37.6W, 30, 1007,
20200906, 1200, , LO, 17.3N, 39.5W, 30, 1006,
20200906, 1800, , LO, 16.9N, 40.5W, 30, 1006,
20200907, 0000, , TD, 16.9N, 41.4W, 30, 1005,
20200907, 0600, , TD, 17.0N, 41.9W, 30, 1005,
20200907, 1200, , TS, 17.1N, 42.2W, 35, 1004,
20200907, 1800, , TS, 17.3N, 42.4W, 40, 1002,
20200908, 0000, , TS, 17.6N, 42.6W, 40, 1001,
20200908, 0600, , TS, 17.9N, 42.8W, 45, 999,
20200908, 1200, , TS, 18.2N, 43.1W, 50, 996,
20200908, 1800, , TS, 18.5N, 43.7W, 55, 993,
20200909, 0000, , TS, 18.8N, 44.4W, 55, 992,
20200909, 0600, , TS, 19.1N, 45.2W, 55, 992,
20200909, 1200, , TS, 19.5N, 46.0W, 55, 991,
20200909, 1800, , TS, 19.9N, 46.8W, 55, 991,
20200910, 0000, , TS, 20.4N, 47.6W, 50, 994,
20200910, 0600, , TS, 20.8N, 48.3W, 50, 994,
20200910, 1200, , TS, 21.3N, 48.9W, 50, 993,
20200910, 1800, , TS, 21.9N, 49.6W, 55, 989,
20200911, 0000, , TS, 22.4N, 50.4W, 60, 986,
20200911, 0600, , TS, 22.9N, 51.2W, 55, 988,
20200911, 1200, , TS, 23.5N, 52.1W, 55, 988,
20200911, 1800, , TS, 24.2N, 53.2W, 55, 987,
20200912, 0000, , TS, 25.4N, 54.3W, 55, 987,
20200912, 0600, , TS, 26.5N, 55.6W, 60, 983,
20200912, 1200, , TS, 27.3N, 56.7W, 60, 982,
20200912, 1800, , TS, 28.1N, 57.9W, 60, 982,
20200913, 0000, , TS, 28.5N, 59.1W, 60, 981,
20200913, 0600, , TS, 29.1N, 60.2W, 60, 979,
20200913, 1200, , HU, 29.6N, 61.4W, 65, 976,
20200913, 1800, , HU, 30.2N, 62.6W, 65, 976,
20200914, 0000, , HU, 30.9N, 63.6W, 70, 973,
20200914, 0600, , HU, 31.8N, 64.4W, 75, 972,
20200914, 0900, L, HU, 32.3N, 64.7W, 75, 970,
20200914, 1200, , HU, 32.9N, 64.9W, 80, 967,
20200914, 1800, , HU, 33.9N, 64.4W, 90, 957,
20200914, 2100, I, HU, 34.5N, 63.9W, 95, 952,
20200915, 0000, , HU, 35.1N, 63.3W, 90, 955,
20200915, 0600, , HU, 36.3N, 62.0W, 90, 955,
20200915, 1200, , HU, 37.6N, 59.3W, 90, 955,
20200915, 1800, , HU, 38.8N, 56.5W, 85, 957,
20200916, 0000, , HU, 40.0N, 54.0W, 85, 957,
20200916, 0600, , HU, 41.2N, 50.8W, 85, 958,
20200916, 1200, , EX, 42.6N, 46.9W, 80, 960,
20200916, 1800, , EX, 44.9N, 43.6W, 70, 968,
20200917, 0000, , EX, 45.1N, 41.0W, 60, 975,

Overall changes are minor. However, the big changes are that the intensity is lowered slightly before Bermuda (75 kt at landfall there) and increased slightly afterward. I estimate that Paulette peaked at 2100Z September 14 (non-synoptic time) when it was closest to T5.5 and some were assigning that. At that time, my estimate is 95 kt. The pressures are also lowered based on trends from when Recon was in the storm (minimum pressure becomes 952 mb).

[AnnularCane]

Is Paulette still out there? Thought they'd at least have a colored circle or something.

[tolakram]

Is Paulette still out there? Thought they'd at least have a colored circle or something.

Top near the center. Giant low now.

[ClarCari]

Post-TC Paulette is now on the TWO at 10/20 odds for right now.
She’s forecasted to move straight south in warmer waters and stall there so she should have a decent shot at becoming tropical again.

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Fri Sep 18 2020

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

3. Post-tropical cyclone Paulette is located several hundred miles
north-northwest of the Azores. The cyclone is forecast to move
quickly southward for the next several days and then stall over
marginally warm waters a few hundred miles south or south-southwest
of the Azores by the end of the weekend. The cyclone could
subsequently redevelop tropical characteristics late this weekend or
early next week while it moves little.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...20 percent.

[ouragans]

3. Post-tropical cyclone Paulette is located several hundred miles north-northwest of the Azores. The cyclone is forecast to move quickly southward for the next few days and then stall over marginally warm waters a few hundred miles south or south-southwest
of the Azores by the end of the weekend. The cyclone could subsequently redevelop tropical characteristics late this weekend or early next week while it moves little.
* Formation chance through 48 hours...low...20 percent.
* Formation chance through 5 days...low...30 percent.

[EquusStorm]

An area of interest diving south from 43N 30W is just peak 2020

[Beef Stew]

We just may end up seeing Paulette active at the same time as Alpha after all.

[AnnularCane]

I keep imagining Paulette waking from her slumber and noticing that the Atlantic is just different now. Like where did Sally go? And who are these new guys?

[gfsperpendicular]

I keep imagining Paulette waking from her slumber and noticing that the Atlantic is just different now. Like where did Sally go? And who are these new guys?

And why does the new girl in the gulf have such a weird name?

[ClarCari]

I keep imagining Paulette waking from her slumber and noticing that the Atlantic is just different now. Like where did Sally go? And who are these new guys?

And why does the new girl in the gulf have such a weird name?

Absolutely floored we could have Beta (or heck maybe even Gamma!) by the time Paulette could reform. That’s a 6-7 name gap!!! Easily demonstrates the most active September on record...ever.