ATL: LARRY - Post-Tropical - Discussion

[aspen]

This small eyewall has become stronger between the 09z and 12z microwave passes, although it isn’t quite complete yet.

[cycloneye]

Inner core looks good.

[Sciencerocks]

[sikkar]

What impressive dual outflow.

[aspen]

With the way Larry’s core is coming together today, it has a good chance of starting RI either tonight or very early tomorrow (EST). The weakening south band and its fantastic outflow setup will help as well. MPIs are able to support a 930-940mb Category 4 hurricane through the next 72 hours before shear picks up.

[cycloneye]

 https://twitter.com/TropicalTidbits/status/1433831181280182277

[galaxy401]

Might be just an illusion with the inner core but it looks like Larry took a more West wobble.

[Kazmit]

Even if Bermuda doesn't get direct impacts the swells are gonna be dangerous. Severe beach erosion is likely. As a surfer, I wish I was on the island right now.

[aspen]

Getting better.

[VBtracker]

[cycloneye]

A. 12L (LARRY)

B. 03/1730Z

C. 14.8N

D. 41.3W

E. THREE/GOES-E

F. T4.5/4.5

G. IR/EIR/VIS

H. REMARKS...16.5/10 BANDING AROUND THE LLCC YIELDS A DT OF 4.5. MET
IS EQUAL TO 5.0 AND PT IS EQUAL TO 4.5 BASED ON A DEVELOPMENT TREND IN
THE LAST 24 HOURS. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...TUGGLE

[cycloneye]

So far is too slow to get plenty of ACE. Unless it does RI soon, the 8 AM of Saturday being cat 3 will not verify.

AL, 12, 2021090318, , BEST, 0, 148N, 415W, 80, 981, HU

[cheezyWXguy]

Larry has some major structural changes going on now, and the hwrf is right - there is going to a very large eye when all is said and done

[aspen]

Larry finally looks like it's ready to bomb out into a major, and conditions look good for it to maintain major status for several days. However, despite the NHC's forecast for weakening to commence early next week, I'm seeing an opportunity for Larry to reach a second (and possibly stronger) peak sometime on Monday.

Starting late Sunday into early Monday, the upper-level environment around Larry looks fantastic, with a big bubble of outflow in all quadrants. This is when the storm will begin moving over SSTs of 28.0-28.5C, warmer than the 27.0-27.5C SSTs it is over now.



As the day progresses, however, it looks like Larry will begin running into problems. A high (red) is present to Larry's SW by Monday night/early Tuesday, which will likely prevent some outflow and induce shear. By the time this happens, Larry will have been over 28.0-28.5C waters for at least 24 hours. This time frame is also when it'll be moving over pockets of OHC as high as 35-50+ kJ cm-2, many times higher than the <15 OHC it's over now.




Larry has about two and a half days before reaching this area, which is plenty of time for an EWRC to start. Therefore, if an EWRC happens at the right time, it'll finish and Larry will begin to strengthen right when it starts moving over the warmest waters of its journey while under a great UL setup. Unless lower-level shear is present at that time, it looks good for a second phase of intensification into a Cat 4.

[Extratropical94]

So far is too slow to get plenty of ACE. Unless it does RI soon, the 8 AM of Saturday being cat 3 will not verify.

AL, 12, 2021090318, , BEST, 0, 148N, 415W, 80, 981, HU

18Z BT has been revised to 85 kts / category 2

AL, 12, 2021090318, , BEST, 0, 148N, 415W, 85, 981, HU

[kevin]

The eye is starting to turn blue on IR:

[Sciencerocks]

[floridasun78]

Bermuda i hope dont get bad hurr nice see out their not affecting land

[galaxy401]

Not surprised in the upgrade to Cat 2. Larry's eye is clearing out.

[kevin]

The eye is just starting to clear out and raw T#'s immediately jump to 5.4. CI# of course still at 4.4, but if it maintains or perhaps even clears out the eye further during the next 6 hours CI will also catch up and then ADT would support roughly 100kt/962mb.

Current Intensity Analysis

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 03 SEP 2021 Time : 192020 UTC
Lat : 15:04:33 N Lon : 41:43:27 W


CI# /Pressure/ Vmax
4.4 / 982.4mb/ 74.6kt


Final T# Adj T# Raw T#
4.4 4.4 5.4

Estimated radius of max. wind based on IR :N/A km

Center Temp : -30.8C Cloud Region Temp : -63.5C

Scene Type : EYE

Subtropical Adjustment : OFF

Extratropical Adjustment : OFF

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : MW ON
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 105nmi
- Environmental MSLP : 1012mb

Satellite Name : GOES16
Satellite Viewing Angle : 42.1 degrees

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