ATL: HELENE - Post-Tropical - Discussion

[kevin]

Crazy that the pressure dropped 7 mb in just one and half hours. Just crazy!

Yep it's insane. I don't have a table of all hurricanes, but if I recall correctly Wilma had an average intensification rate of 4 mb/hr over a period of 24 hours with a peak of 9 mb/hr. With 7 mb/hr Helene is now even more extreme than Wilma's 24 hour deepening and approaching the all-time short-term intensification record of 9 mb/hr. She may have struggled for a while, but she's putting up quite a show now.

[Hypercane_Kyle]

Some extremely intense convection firing off in the NW eyewall. Should be enough to push it to Cat 4.



Tropical storm winds expand greater than 200 miles when compared to Ian.

In a lot of ways, it's a more eastern version of Hurricane Ivan.

[BIFF_THE_UNRULY]

Crazy that the pressure dropped 7 mb in just one and half hours. Just crazy!

Yep it's insane. I don't have a table of all hurricanes, but if I recall correctly Wilma had an average intensification rate of 4 mb/hr over a period of 24 hours with a peak of 9 mb/hr. With 7 mb/hr Helene is now even more extreme than Wilma's 24 hour deepening and approaching the all-time short-term intensification record of 9 mb/hr. She may have struggled for a while, but she's putting up quite a show now.

lol it was something like that. We fell asleep to a Tropical storm and woke up with a 220mph Category 5

That was some year! haha . Wasnt Just Wilma either. They all did it that year. Rita, Katrina, Emily, Dennis, I am sure there are others i missed because we had like 45 storms in 2005.

[Kazmit]

[LandoWill]

I wonder if it's going to rain heh

[BIFF_THE_UNRULY]

I wonder if it's going to rain heh

I am starting to doubt. The wind is so unbearably hot its like a blow dryyer. Very unusual wind temperature

[ScottNAtlanta]

You can see the eye tightening

[NC George]

Quick question regarding storm surge. Does a faster storm mean stronger surge? I know the larger the hurricane, the higher the waves but does speed play a role as well? I imagine it probably does.

So the main three factors in storm surge are wind speed, fetch and duration. Fetch is the distance the winds blow, and duration is how long they blow. So a faster moving storm would have less duration than a slower moving storm, so less surge. However, this is a very large storm, so fetch is higher than usual.

[Hugo1989]

I wonder if it's going to rain heh

I am starting to doubt. The wind is so unbearably hot its like a blow dryyer. Very unusual wind temperature

It's so weird. I am 5 minutes away from the Ruskin Radar and I spent some time outside and I felt out of air.

[NDG]

Calculations show me that Helene is now moving on a 19 deg heading during the past 5-6 hours, compared to 25 deg heading during the morning, it will have to start moving almost on a due north heading to track over Tallahassee.

[BIFF_THE_UNRULY]

Calculations show me that Helene is now moving on a 19 deg heading during the past 5-6 hours, compared to 25 deg heading during the morning, it will have to start moving almost on a due north heading to track over Tallahassee.

Klystron 9 showing a slight eastern path than the NHC line but well within the Cone

For anyone interested, the eyewall is on Tampa Radar now

https://baynews9.com/fl/tampa/weather/radar

[LAwxrgal]

This storm is booking it, at 21 miles an hour to the NNE, according to the advisory.

Do major hurricanes usually travel that fast?

If so, this storm should be on land pretty soon.

[ConvergenceZone]

Some extremely intense convection firing off in the NW eyewall. Should be enough to push it to Cat 4.

https://i.imgur.com/2UMYZ3B.jpeg

Tropical storm winds expand greater than 200 miles when compared to Ian.

In a lot of ways, it's a more eastern version of Hurricane Ivan.

very possible at this point! It does seem like a cat 4 run before landfall. It will be interesting to read the next NHC discussion.

[BIFF_THE_UNRULY]

This storm is booking it, at 21 miles an hour to the NNE, according to the advisory.

Do major hurricanes usually travel that fast?

If so, this storm should be on land pretty soon.

Will be on land in 4 hours or so

[aspen]

It’s been hours of wrapping convective bursts, and the eye has still not cleared. I’m doubtful it will; several hurricane model runs predicted this.

[Teban54]

Crazy that the pressure dropped 7 mb in just one and half hours. Just crazy!

Yep it's insane. I don't have a table of all hurricanes, but if I recall correctly Wilma had an average intensification rate of 4 mb/hr over a period of 24 hours with a peak of 9 mb/hr. With 7 mb/hr Helene is now even more extreme than Wilma's 24 hour deepening and approaching the all-time short-term intensification record of 9 mb/hr. She may have struggled for a while, but she's putting up quite a show now.

Didn't Iota have a drop of 10 mb/hr during one recon mission? Someone was even trying to add it to the Wikipedia page of Atlantic hurricane records at one point, but it was removed later because hour-by-hour pressure changes are rarely measured accurately.

[BIFF_THE_UNRULY]

I wonder if it's going to rain heh

I am starting to doubt. The wind is so unbearably hot its like a blow dryyer. Very unusual wind temperature

It's so weird. I am 5 minutes away from the Ruskin Radar and I spent some time outside and I felt out of air.

yes its very peculiar. does not feel like any hurricane ive ever felt.

[Teban54]

It’s been hours of wrapping convective bursts, and the eye has still not cleared. I’m doubtful it will; several hurricane model runs predicted this.

IIRC, Michael didn't really have a clear eye until just before landfall as a Cat 5.

[grapealcoholic]

I believe they reported hail in the eyewall of Iota

[otowntiger]

Interestingly they are reporting the eyewall as ragged:
https://i.imgur.com/OzIMTz3.png

it is ragged- just look at the radar imagery.