ATL: KIRK - Post-Tropical - Discussion

[Teban54]

Tropical Storm Kirk Advisory Number 4
NWS National Hurricane Center Miami FL AL122024
1100 AM AST Mon Sep 30 2024

...KIRK STRENGTHENING OVER THE TROPICAL ATLANTIC...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...13.5N 34.8W
ABOUT 740 MI...1195 KM WSW OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES
...

Hmm, 45 kts definite sounds ahead of schedule. The previous advisory (at 5am EDT) had 40 kts three hours from now and 50 kts another 12 hours later.

Forecast peak is now up to 110 kts, with a 70 kt hurricane less than 24 hours from now.

Satellite images show an expanding area of central convection near
the system with the low-level center on the western side of the deep
convection. Microwave data from a few hours ago showed that an
inner core is forming, with a partial eyewall noted on an AMSU
pass. The initial wind speed is set to 45 kt based on 40-45 kt
winds from a pair of recent scatterometer passes.

[Travorum]

NHC is now forecasting an increased rate of strengthening given the AMSU-B pass showing a developing core, but note that rapid development and the large projected size of Kirk will make it more prone to ERCs. FWIW hurricane models are in good consensus about future ERCs. From the 1100am discussion:

Given the formation
of an inner core, the rate of strengthening has been raised in the
short term, and rapid intensification is a distinct possibility.
The biggest negative to this system is probably its large size,
which could eventually promote eyewall replacement cycles and some
SST cooling ahead of the system.

[ChrisH-UK]

This is a 2 hour loop of GOES-16 Meso Sector using Cloud Optical Depth. As you can see there is an elongated circulation in the structure that is starting to become smaller as a new convection burst fils it in.

Source - https://col.st/DUc8w

[sunnyday]

Any idea where it might be headed?

[cycloneye]

Already they edited the best track and it was a storm at 06z, which means, the TSR will have fixes.



https://ftp.nhc.noaa.gov/atcf/btk/bal122024.dat

[aspen]

Any idea where it might be headed?

Almost certainly OTS, recurving well east of Bermuda. Maybe the Azores might have to watch out for its post-tropical remnants but otherwise it should be a safe OTS major.

The possible system behind Kirk, however, has potential to get further west and maybe threaten the islands. For now I think Kirk will keep it weak or open an escape path for it.

[sunnyday]

Thank you, Aspen.

[HurricaneAndre2008]

I think Kirk is 60 to 70mph storm right now.

[HurricaneAndre2008]

Tropical Storm 12L


UW-CIMSS Automated Satellite-Based
Advanced Dvorak Technique (ADT)
Version 9.1

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 30 SEP 2024 Time : 171020 UTC
Lat : 13:32:14 N Lon : 35:10:13 W


CI# /Pressure/ Vmax
3.7 / 991.9mb/ 59.0kt


Final T# Adj T# Raw T#
3.7 3.7 3.7

[cycloneye]

Up to 50kt.

AL, 12, 2024093018, , BEST, 0, 135N, 351W, 50, 999, TS

[Travorum]

Improvement in the western half of the core since this morning's AMSU pass:

[abajan]

I wouldn't be surprised if Kirk were to be upgraded to a hurricane in the next NHC advisory.

[cycloneye]

AL, 12, 2024100100, , BEST, 0, 142N, 363W, 50, 998, TS

[zzzh]

It's getting that look, should be a hurricane soon.

[xtyphooncyclonex]

Big-ACE fishes are by far the best storms to track. Hoping Kirk wouldn't let us down.

Thinking 40 ACE might not be a stretch at all.

[Hypercane_Kyle]

Definitely quite the large tropical storm. Still organizing, no inner core as of yet.

[zzzh]

Buoy 13008 (15N 38W) recorded 996.3mb as of 07z.

[cycloneye]

AL, 12, 2024100112, , BEST, 0, 150N, 387W, 55, 992, TS

[Sciencerocks]

[zzzh]

https://www.ndbc.noaa.gov/station_page.php?station=13008
Buoy 13008 recorded 990.2mb at 09z (this buoy records data every 1h). 09z NHC advisory had 998mb