ATL: ISAAC - Extratropical - Discussion

[weeniepatrol]

All eyes are elsewhere, but a cursory glance at Isaac reveals that it is, indeed, September.

Probably at LEAST 65 kt atm.

[galaxy401]

Best Track up to 50 kts but I feel that is too low.

[aspen]

Probably a hurricane now. Knowing how the NHC does with high-latitude storms as of late (TC1 ‘23 being missed altogether and Ernesto’s underestimated second peak), I’m willing to bet Issac will obviously be a hurricane but doesn’t get classified as one operationally thanks to low ADT.

[Hurricane2022]

...ISAAC STRENGTHENING AND LIKELY TO BECOME A HURRICANE SOON...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...37.1N 49.8W
ABOUT 1245 MI...2005 KM W OF THE AZORES
ABOUT 910 MI...1470 KM ENE OF BERMUDA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...E OR 90 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...992 MB...29.30 INCHES

[Beef Stew]

I think there's a non-zero chance we have two hurricanes and a tropical storm all active right now.

[Buck]

I think there's a non-zero chance we have two hurricanes and a tropical storm all active right now.

I’m inclined to agree.

[ChrisH-UK]

CIMSS's real time tropical cyclone intensity product has it just below hurricane strength.

Source - https://tropic.ssec.wisc.edu/real-time/ ... ry_IR.html

[weeniepatrol]

lol

[Hurricane2022]

Habemus Hurricane Isaac.

...ISAAC BECOMES A HURRICANE...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...37.0N 48.5W
ABOUT 1175 MI...1895 KM W OF THE AZORES
ABOUT 980 MI...1575 KM ENE OF BERMUDA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...E OR 90 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...981 MB...28.97 INCHES

[Sciencerocks]

[Teban54]

Pleasantly surprised they pulled the trigger, though the current organization of Isaac doesn't leave them much choice.

Forecast now has 75 kt peak. Not shabby at all for a storm that nobody expected to form in the first place!

[aspen]

GOES imagery is lagging behind on Tropical Tidbits, but Issac looks stronger than just 65 kt. Could already be 75-80 kt based on the moderately deep convection around a tight core.

[aspen]

From the 11am discussion:

Subjective and objective Dvorak estimates range widely
from 35 kt to 73 kt and the initial intensity is held at 65 kt for
this advisory, closest to the SAB classification.

Man, Dvorak is awful with these high-latitude system.

[Travorum]

Pleasantly surprised they pulled the trigger, though the current organization of Isaac doesn't leave them much choice.

Forecast now has 75 kt peak. Not shabby at all for a storm that nobody expected to form in the first place!

An SAR pass from 7 hours ago shows it might already be there:

Platform: RCM-2
Acquisition Date: 2024-09-27 09:13:53 UTC
Storm Name: AL102024 / ISAAC
Storm ID: AL10
Storm Center Longitude: -48.537
Storm Center Latitude: 37.008
Incidence Angle (Degrees): 45.548
Quadrant 1 NE VMax (kts): 71.77
Quadrant 2 SE VMax (kts): 76.77
Quadrant 3 SW VMax (kts): 71.23
Quadrant 4 NW VMax (kts): 69.96
RMax (nmi): 12.00 - 19.00

[HurricaneAndre2008]

Hurricane 10L


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 : 27 SEP 2024 Time : 171020 UTC
Lat : 37:14:24 N Lon : 46:46:12 W


CI# /Pressure/ Vmax
4.4 / 969.7mb/ 74.6kt


Final T# Adj T# Raw T#
4.4 4.4 2.7

[cycloneye]

Bumped at BT up to 75kt.

AL, 10, 2024092718, , BEST, 0, 375N, 462W, 75, 976, HU

[Sciencerocks]

[Hurricane2022]

Bumped at BT up to 75kt.

AL, 10, 2024092718, , BEST, 0, 375N, 462W, 75, 976, HU

So it's likely that Isaac is a Category 2 hurricane in reality
I hope the NHC overrides this estimate to 80 kt.

[AnnularCane]

https://i.imgur.com/J7OD691.gif

What a cute fellow.

[HurricaneAndre2008]

Hurricane 10L


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 : 27 SEP 2024 Time : 201020 UTC
Lat : 37:48:21 N Lon : 45:17:40 W


CI# /Pressure/ Vmax
4.5 / 968.7mb/ 77.0kt


Final T# Adj T# Raw T#
4.5 4.5 3.1