ATL: FIONA - Post-Tropical - Discussion

[AtlanticWind]

The circulation does look weaker than earlier today

[InfernoFlameCat]

Convection is going to explode over the western part of the storm over night. Hwrf predicted the anemic form last night before rapidly developing it. Also, there are signs on radar that some big boomers are about to form around the eyewall.

[skyline385]

Not sure what this is but its something

Seems to be getting destroyed by dry air

https://i.imgur.com/qLpaavZ.jpeg

I don't think it's dry air that is the problem here, it could be the DMIN since the sun is setting.

Check out the black patch on WV killing off the bands in the west

[IsabelaWeather]

Not sure what this is but its something

Seems to be getting destroyed by dry air

https://i.imgur.com/qLpaavZ.jpeg

I don't think it's dry air that is the problem here, it could be the DMIN since the sun is setting.

Check out the black patch on WV killing off the bands in the west

https://s4.gifyu.com/images/goes16_wv-mid_07L_202209172135.gif

I dont believe dry air is the problem, nowhere have I heard dry air will be a problem.

What I have noticed are storms seem to fall apart quickly after they get organized only to explode later on.

[Hammy]

Despite the lackluster convection tonight, this is the best Fiona’s structure has been all day. It now has a focused and stacked LLC, as well as a developing eyewall on radar and microwave. Its IR appearance is also quite close to what the 18z HWRF showed for this time.

Organization is quite poor at the moment, winds get stronger as you move away from the center. This likely won't strengthen much, and appears to have weakened from earlier. But it's quite likely (as with Laura in 2020 among others) that moving over Puerto Rico will tighten it up after, as often happens with broad storms.

[Iceresistance]

Eye Dropsonde of 998 MB with 17 knots of wind.

[Dean4Storms]

16.3N? It's jogged a little WSW.

[Hammy]

recon fix

[Iceresistance]

16.3N? It's jogged a little WSW.

I'm increasingly becoming concerned about the possibility of Fiona threading the needle between Hispaniola and Puerto Rico. She would have less land interaction and more opportunity to become even stronger.

[NDG]

I think the dry air disrupted the nice eyewall like feature it had earlier and convection that it had in the NW quadrant.

Latest vortex:

247
URNT12 KNHC 180032
VORTEX DATA MESSAGE AL072022
A. 17/23:41:40Z
B. 16.30 deg N 064.69 deg W
C. 700 mb 3056 m
D. 998 mb
E. 325 deg 17 kt
F. NA
G. NA
H. 46 kt
I. 114 deg 61 nm 23:23:30Z
J. 220 deg 43 kt
K. 113 deg 59 nm 23:24:00Z
L. 34 kt
M. 313 deg 99 nm 00:11:00Z
N. 067 deg 55 kt
O. 313 deg 92 nm 00:09:00Z
P. 8 C / 3046 m
Q. 12 C / 3053 m
R. 7 C / NA
S. 1345 / 7
T. 0.02 / 1 nm
U. AF303 0907A FIONA OB 06
MAX FL WIND 55 KT 313 / 92 NM 00:09:00Z
;

[skyline385]

I don't think it's dry air that is the problem here, it could be the DMIN since the sun is setting.

Check out the black patch on WV killing off the bands in the west

https://s4.gifyu.com/images/goes16_wv-mid_07L_202209172135.gif

I dont believe dry air is the problem, nowhere have I heard dry air will be a problem.

What I have noticed are storms seem to fall apart quickly after they get organized only to explode later on.

Here's the dry air on HWRF killing off its western bands, and almost getting into the core through the west. The location matches perfectly on the water vapour I posted as well. The HWRF also got this pretty well on IR.

[skyline385]

16.3N? It's jogged a little WSW.

I'm increasingly becoming concerned about the possibility of Fiona threading the needle between Hispaniola and Puerto Rico. She would have less land interaction and more opportunity to become even stronger.

But then she basically goes OTS without making any landfall though. Obviously the rain will still be a problem but atleast the islands escape the strongest winds.

[Iceresistance]

Check out the black patch on WV killing off the bands in the west

https://s4.gifyu.com/images/goes16_wv-mid_07L_202209172135.gif

I dont believe dry air is the problem, nowhere have I heard dry air will be a problem.

What I have noticed are storms seem to fall apart quickly after they get organized only to explode later on.

Here's the dry air on HWRF killing off its western bands, and almost getting into the core through the west. The location matches perfectly on the water vapour I posted as well.

https://i.imgur.com/X7a12F9.png

I'm impressed that the model predicted it almost perfectly.

[Kingarabian]

Ok guys and gals. I will shut down as the winds are starting to pick up here in PR and the power grid will go. Hopefully I will be back sooner than when Maria as I was 2 months without power and internet.

Good luck stay safe!

[Hammy]

I dont believe dry air is the problem, nowhere have I heard dry air will be a problem.

What I have noticed are storms seem to fall apart quickly after they get organized only to explode later on.

Here's the dry air on HWRF killing off its western bands, and almost getting into the core through the west. The location matches perfectly on the water vapour I posted as well.

https://i.imgur.com/X7a12F9.png

I'm impressed that the model predicted it almost perfectly.

Not doing well beyond 6h though, 00z run had it 982mb by now and much tighter.

[Stellar]

The latest COC is more than a half degree south of the predicted position at 00Z. Should the dry air being ingested into the storm continue to disrupt the core, is is conceivable that the storm would remain disorganized and not only miss PR but miss the Mona Passage and cross the island of Hispaniola before beginning it's northward turn and intensification?

[skyline385]

Yea this isn’t looking good for the storm, can see the western eyewall eroding on radar as well

[pgoss11]

The latest COC is more than a half degree south of the predicted position at 00Z. Should the dry air being ingested into the storm continue to disrupt the core, is is conceivable that the storm would remain disorganized and not only miss PR but miss the Mona Passage and cross the island of Hispaniola before beginning it's northward turn and intensification?

The 00z models will be interesting. Not sure if this SW drop is just a temporary jog but the 8:00 update said the heading was wnw. Hopefully Puerto Rico can avoid a landfall.

[skyline385]

Current Intensity Analysis

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

----- Current Analysis -----
Date : 18 SEP 2022 Time : 002020 UTC
Lat : 16:51:34 N Lon : 64:59:53 W


CI# /Pressure/ Vmax
4.0 / 985mb / 65kts


Final T# Adj T# Raw T#
3.2 3.3 2.1

Center Temp : -15.1C Cloud Region Temp : -43.8C

Scene Type : CURVED BAND with 0.38 ARC in LT GRAY
Maximum CURVED BAND with 0.48 ARC in LT GRAY
at Lat: 16:38:59 N Lon: 64:35:23 W

Well we know from recon that its most definitely not at 985mb lol

[Iceresistance]

Current Intensity Analysis

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

----- Current Analysis -----
Date : 18 SEP 2022 Time : 002020 UTC
Lat : 16:51:34 N Lon : 64:59:53 W


CI# /Pressure/ Vmax
4.0 / 985mb / 65kts


Final T# Adj T# Raw T#
3.2 3.3 2.1

Center Temp : -15.1C Cloud Region Temp : -43.8C

Scene Type : CURVED BAND with 0.38 ARC in LT GRAY
Maximum CURVED BAND with 0.48 ARC in LT GRAY
at Lat: 16:38:59 N Lon: 64:35:23 W

Well we know from recon that its most definitely not at 985mb lol

Also want to mention that it has the "Rapid Dissipation Flag" on right now.