NATL: MELISSA - Hurricane - Discussion

[Hurricane2022]

943.6 extrap - intensifying again!

[Hurricane2022]

 https://x.com/TheSteveCop/status/1982507691525513234

 https://x.com/WeathermanAAA_/status/1982509651079074124

[kevin]

FL winds only peaked at 119 kt this pass which still doesn't support much more than 110 kt at the surface. The extrapolated pressure has fallen from 946.9 mb with 7 kt -> 946.2 mb to 943.6 mb with 9 kt -> 942.7 mb. That's roughly a 3.5 mb drop in 80 minutes or 2.6 mb/h. Definitely deepening, not per se at the rate that one would expect with a pinhole. But if an EWRC cycle were starting you'd expect practically zero deepening which is also not the case. Still a bit of a puzzle, but she is getting stronger at the moment.

[Hurricane2022]

 https://x.com/AndyHazelton/status/1982482770782818347

[aspen]

Even as a mature hurricane, Melissa isn’t making it easy on us lol.

Between its incredibly complex track forecast for the better part of a week and its stair-stepping, erratic intensification phase, this is likely one of the most difficult TCs to forecast and assess in a long time.

[WaveBreaking]

[cycloneye]

Dropsonde down to 945 mbs.

[eastcoastFL]

 https://x.com/TheSteveCop/status/1982507691525513234

 https://x.com/WeathermanAAA_/status/1982509651079074124

Not what I wanted to see, especially with so much time left before landfall. This could spell additional trouble for cuba and Hispaniola as well as they're already dealing with a lot of rain.

[zzzh]

FL winds only peaked at 119 kt this pass which still doesn't support much more than 110 kt at the surface. The extrapolated pressure has fallen from 946.9 mb with 7 kt -> 946.2 mb to 943.6 mb with 9 kt -> 942.7 mb. That's roughly a 3.5 mb drop in 80 minutes or 2.6 mb/h. Definitely deepening, not per se at the rate that one would expect with a pinhole. But if an EWRC cycle were starting you'd expect practically zero deepening which is also not the case. Still a bit of a puzzle, but she is getting stronger at the moment.

You can't use flight level wind for pressure conversion

[GCANE]

Anticyclone is moving west away from Melissa.
Wrong direction if Melissa wants to strengthen further.

Vort interference at 925 and 500 mb.

Strong infeed now of EPAC high-TPW air thru southern Nicaragua.

IMHO, 50/50 chance this could strengthen more near and after dusk.

[eastcoastFL]

Even as a mature hurricane, Melissa isn’t making it easy on us lol.

Between its incredibly complex track forecast for the better part of a week and its stair-stepping, erratic intensification phase, this is likely one of the most difficult TCs to forecast and assess in a long time.

So far the NHC has done really well with track. They had one little hiccup when she was first forming but since then it's been rock solid.

[zzzh]

[Iceresistance]

A C6 eye? Hello?

148
URNT12 KNHC 261823
VORTEX DATA MESSAGE AL132025
A. 26/18:05:40Z
B. 16.38 deg N 076.93 deg W
C. 700 mb 2651 m
D. 945 mb
E. 065 deg 9 kt
F. CLOSED
G. C6
H. 106 kt
I. 217 deg 3 nm 18:04:30Z
J. 308 deg 107 kt
K. 219 deg 5 nm 18:04:00Z
L. 115 kt
M. 025 deg 9 nm 18:08:30Z
N. 116 deg 119 kt
O. 024 deg 11 nm 18:09:00Z
P. 10 C / 3047 m
Q. 20 C / 3041 m
R. 8 C / NA
S. 12345 / 07
T. 0.02 / 1 nm
U. AF307 1613A MELISSA OB 15
MAX FL WIND 122 KT 110 / 9 NM 16:42:00Z

[Teban54]

[GCANE]

As advertised.
Down to a pinhole.

[cheezyWXguy]

Given the discussion we’ve had earlier in the day about this persistent band feature, I’m very closely watching what happens with the newer convection that has popped on the southeastern, eastern side. So far, it seems to be streaming northward, eventually into the circulation, as opposed to staying put and stealing energy from the circulation like the previous band did. If this is actually true, I think it should be noted that there’s a distinction between these two types and their impacts on storm intensification trends, but we’ll have to wait and see.

[cheezyWXguy]

As advertised.
Down to a pinhole.

Gotta give credit here, you were right. I didn’t think the eye would contract to this degree when it was originally forming.

[Iceresistance]

As advertised.
Down to a pinhole.

Gotta give credit here, you were right. I didn’t think the eye would contract to this degree when it was originally forming.

I knew the eye was going to contract, but I didn't think it was going to contract to a pinhole this quickly

[GCANE]

Next thing to watch for is a drop in relative humidity in the eye.
That will be the onset of an EWRC.

[Sciencerocks]