ATL: HELENE - Post-Tropical - Discussion

[Steve]

The upper low is now NW of the Yucatan with some trailing energy. It should deflect some of the outflow influence from John seen at the bottom left of the view. 9 is likely to feed off some of this if it establishes that Pacific Channel.

https://www.tropicaltidbits.com/sat/sat ... uct=wv_mid

Take it a little farther out to the W Atlantic view and you can see the future pattern reversal. Should be good upper support almost to the coast. Not sure how far right it can get with that ridge off the coast meaning I don't think it will go offshore of the east coast of Florida. But it still can come in anywhere.

https://www.tropicaltidbits.com/sat/sat ... uct=wv_mid

WV doesn't get enough love. Look at the trough digging. For days, we have waited to see where it would set up and how sharp. It is still developing, but you could not look at a model the next couple of days and put together a good track with just the WV. Keep your fingers crossed, Tampa and points south.

No it doesn't get enough love. It's the one satellite view that sums up most of we see in the mid and upper patterns which generally are where steering will be with actual hurricanes. I particularly like it when we get into so-called now cast mode where we're not just watching the models but the actual evolution. It's always got the clues.

[Michele B]

i wont sleep better in Tampa or anywhere else is south florida till the storms develops and start moving north and models are still firm set on the nature coast.

Next 24 hours are a big deal here

At this point I trust the consensus that this is headed towards the big bend

Not me. I'm in the camp that experienced the full force of Charley and then Ian - who were both forecast to head well north of us.

I will not take my eyes off this one until it is north of my latitude.

[DunedinDave]

I don’t know how many remember Hurricane Maria here, but it took 48 hours to go from a weak TS to a category 5 monster. And this water is warmer than what Maria went through.

Katrina is another good example. It went from a weak TS leaving the Florida coast to a 175mph storm within 48 hours.

So for anyone who says it doesn’t have time to get to cat 4 or higher status, I’d say that history would disagree with you.

I dont think any of the NHC folks saying it cannot reach CAT4/5 status. Just that at this time it is not in the forecast. Things can and do change. Just be prepared is the understatement.

I've seen some here mention it, that's why I brought it up. The thought for some is "Well the GFS and Euro don't forecast it so it won't get that strong." That's a whole other conversation I won't get into but it can definitely crank up a lot more than what the GFS and Euro show.

[WeatherBoy2000]

12z Best Track has no upgrade to TD or TS, but the presure is down to 1000 mbs.

AL, 09, 2024092412, , BEST, 0, 194N, 837W, 30, 1000, DB

At this point the delayed TD/TS designation might actually give NINE the possibility to compete for some of the Atlantic all-time intensification records. TD to C5 seems like the most realistic one (if NINE reaches that intensity at all). The other Wilma records feel like they're out of reach, what an unbelievable storm that was.

Fastest intensification from a TD to a hurricane = 12 hours (Harvey 1981)
Fastest intensification from a TD to a C5 hurricane = 54 hours (Wilma 2005, Felix 2007)
Fastest intensification from a TS to a C5 hurricane = 24 hours (Wilma 2005)
Maximum pressure drop in 12 hours = 83 mbar (Wilma 2005, 975 mbar -> 892 mbar)
Maximum pressure drop in 24 hours – 97 mbar (Wilma 2005, 979 mbar -> 882 mbar)

Is there a category for how long a PTC takes to become a named storm?!?! I think NINE is in the running for this award.

Bonnie 2022 spent far more of its time as a PTC than as a TC (not counting its life in the Pacific), this won't come close.

[Teban54]

12z Best Track has no upgrade to TD or TS, but the presure is down to 1000 mbs.

AL, 09, 2024092412, , BEST, 0, 194N, 837W, 30, 1000, DB

At this point the delayed TD/TS designation might actually give NINE the possibility to compete for some of the Atlantic all-time intensification records. TD to C5 seems like the most realistic one (if NINE reaches that intensity at all). The other Wilma records feel like they're out of reach, what an unbelievable storm that was.

Fastest intensification from a TD to a hurricane = 12 hours (Harvey 1981)
Fastest intensification from a TD to a C5 hurricane = 54 hours (Wilma 2005, Felix 2007)
Fastest intensification from a TS to a C5 hurricane = 24 hours (Wilma 2005)
Maximum pressure drop in 12 hours = 83 mbar (Wilma 2005, 975 mbar -> 892 mbar)
Maximum pressure drop in 24 hours – 97 mbar (Wilma 2005, 979 mbar -> 882 mbar)

Is there a category for how long a PTC takes to become a named storm?!?! I think NINE is in the running for this award.

I'm fairly sure that belongs to pre-Bonnie 2022. PTC 9 isn't even close.

[Pipelines182]

I don’t know how many remember Hurricane Maria here, but it took 48 hours to go from a weak TS to a category 5 monster. And this water is warmer than what Maria went through.

Katrina is another good example. It went from a weak TS leaving the Florida coast to a 175mph storm within 48 hours.

So for anyone who says it doesn’t have time to get to cat 4 or higher status, I’d say that history would disagree with you.

I dont think any of the NHC folks saying it cannot reach CAT4/5 status. Just that at this time it is not in the forecast. Things can and do change. Just be prepared is the understatement.

I've seen some here mention it, that's why I brought it up. The thought for some is "Well the GFS and Euro don't forecast it so it won't get that strong." That's a whole other conversation I won't get into but it can definitely crank up a lot more than what the GFS and Euro show.

Everyone needs to stop looking to the Euro for intensity, it is not an intensity model, it has a horrible track record for intensity.

[kevin]

At this point the delayed TD/TS designation might actually give NINE the possibility to compete for some of the Atlantic all-time intensification records. TD to C5 seems like the most realistic one (if NINE reaches that intensity at all). The other Wilma records feel like they're out of reach, what an unbelievable storm that was.

Fastest intensification from a TD to a hurricane = 12 hours (Harvey 1981)
Fastest intensification from a TD to a C5 hurricane = 54 hours (Wilma 2005, Felix 2007)
Fastest intensification from a TS to a C5 hurricane = 24 hours (Wilma 2005)
Maximum pressure drop in 12 hours = 83 mbar (Wilma 2005, 975 mbar -> 892 mbar)
Maximum pressure drop in 24 hours – 97 mbar (Wilma 2005, 979 mbar -> 882 mbar)

Is there a category for how long a PTC takes to become a named storm?!?! I think NINE is in the running for this award.

I'm fairly sure that belongs to pre-Bonnie 2022. PTC 9 isn't even close.

Bonnie must've been one of the worst storms to track since I've been on the forum. I think it took like 4 or 5 days before it went from a PTC to a TS just before landfall. Almost made me want to give up on the season altogether.

[beachnut]

i wont sleep better in Tampa or anywhere else is south florida till the storms develops and start moving north and models are still firm set on the nature coast.

Next 24 hours are a big deal here

At this point I trust the consensus that this is headed towards the big bend

Not me. I'm in the camp that experienced the full force of Charley and then Ian - who were both forecast to head well north of us.

I will not take my eyes off this one until it is north of my latitude.

Same here Michelle. The old "fool me once" saying comes to mind.

[Steve]

I see a lot of talk about the right hooks many storms make on approach to landfall along the west coast of Florida and the Big Bend. I was thinking that was likely to occur too; however, one item sticks out as a difference to those situations. The upper low over the southeast is going to impart a NW motion after landfall. A right hook followed by a left hook means I think the track forecast could more likely error in either direction versus the normal trough pulling the storm northeast.

That is true. The storm will be steered by the upper low over Arkansas Wednesday that is moving SW. That will result in a gradual turn to the NW Thursday night/Friday. Uncertainty is how close to Tampa will it pass Thursday morning before the more northerly track?

With that eventual left turn, I'm curious how close this gets to Atlanta, and how much punch she will still be packing at that time. Atlanta doesn't really do well with tropical systems. This isn't to take away from the immediate Florida threat, just something I've been thinking about with that NW trajectory after landfall.

Yeah soup. As the 12z models come out, run them at "total accumulated precipitation" and you'll get the respective paths of where the heaviest rain (and path of center) is anticipated by a given model. If you use Tropical Tidbits look down at Precip/Moisture and click "Total Accumulated Precipitation" You can then press play and it will fill in the anticipated rainfall as well as click "x" days out and see what's on the ground at a given time. For instance, this is the 06GFS out to 180 hours (7.5 days) showing a few inches there.

https://www.tropicaltidbits.com/analysi ... 406&fh=180

Here's the 06z ICON out to 120 hours because that's all that comes up there for the 6z run. Notice 1-2 feet in the general area of the ATL.
https://www.tropicaltidbits.com/analysi ... 406&fh=120

And just because, here's the 00z CMC which has heavy rains in Atlanta as well but focuses the energy on western SC and particularly the Great Smoky Mountains.
https://www.tropicaltidbits.com/analysi ... 400&fh=150

There are a bunch of wind features you can look at as well. There are better sites than Levi's for that where you can click a specific point and get max winds. There is a ton of stuff available with these model runs (temperature, humidity, rainfall/snowfall, pressure patterns, winds, etc.).

[SFLcane]

The upper low is now NW of the Yucatan with some trailing energy. It should deflect some of the outflow influence from John seen at the bottom left of the view. 9 is likely to feed off some of this if it establishes that Pacific Channel.

https://www.tropicaltidbits.com/sat/sat ... uct=wv_mid

Take it a little farther out to the W Atlantic view and you can see the future pattern reversal. Should be good upper support almost to the coast. Not sure how far right it can get with that ridge off the coast meaning I don't think it will go offshore of the east coast of Florida. But it still can come in anywhere.

https://www.tropicaltidbits.com/sat/sat ... uct=wv_mid

WV doesn't get enough love. Look at the trough digging. For days, we have waited to see where it would set up and how sharp. It is still developing, but you could not look at a model the next couple of days and put together a good track with just the WV. Keep your fingers crossed, Tampa and points south.

Could surely see some outages across the area. Have to wait and see how close it gets. Huge windfield!

Graphic via Craigsetzer

[Zonacane]

https://x.com/cyclonicwx/status/1838578 ... 38518?s=61

The Tail Doppler Radar data from #PTC9 shows a solid low-level center. Seems like we've got a TC on our hands now. What's more interesting is this LLC is stacked with the MLC at 5km! Looks to be organizing now

Reminder that TDR data is now available at cyclonicwx.com/recon/!

[Poonwalker]

The most disturbing thing I have read today is wxman57 saying watch the Icon model. Sheesh

[Stormlover70]

I don’t know how many remember Hurricane Maria here, but it took 48 hours to go from a weak TS to a category 5 monster. And this water is warmer than what Maria went through.

Katrina is another good example. It went from a weak TS leaving the Florida coast to a 175mph storm within 48 hours.

So for anyone who says it doesn’t have time to get to cat 4 or higher status, I’d say that history would disagree with you.

I remember Katrina strengthening over the south florida area. It was over land. Had a bad feeling of things to come.....

[underthwx]

Wxman is one of the forum's most experienced and knowlegable members. Thank you for all your valuable contributions. I guess his years of experience have made him a bit more conservative regarding storm intensity compared to others on the forum (like me ). Because of this, whenever he does put out concerning messages or warnings regarding a TC I'm immediately on high alert. We all know what happened to Ian's east shifts, it doesn't take much for this to change to a MH storm surge event for Tampa.

I agree Kevin......Xman is valuable to Storm 2K....he is among many here on 2K...that are phenomenally gifted with weather knowledge.....including yourself bro....

[Travorum]

https://x.com/cyclonicwx/status/1838578426795438518?s=61

The Tail Doppler Radar data from #PTC9 shows a solid low-level center. Seems like we've got a TC on our hands now. What's more interesting is this LLC is stacked with the MLC at 5km! Looks to be organizing now

Reminder that TDR data is now available at cyclonicwx.com/recon/!

https://imgur.com/a/sW449k6

Looks like a pretty strong case for a TS at 11:00, I always love the data from the tail doppler radar.

TDR center fixes confirm the increase in vertical alignment over the pass several hours, and the general WNW current track:

[DunedinDave]

The most disturbing thing I have read today is wxman57 saying watch the Icon model. Sheesh

ICON should start running here within the next 20 minutes so we'll get a good update here very fast on that model.

[jlauderdal]

The most disturbing thing I have read today is wxman57 saying watch the Icon model. Sheesh

He said it yesterday too and others have been saying it for a few days, it has had some big wins in this part of the basin. it carries real weight so watch the trend, not the windshield wipers.

[Nimbus]

Western quadrants still exposed probably near 19.9 -84.4 now should be Hermine?

[Lightning48]

Good morning. I believe I read a few post back that cyclone had mentioned that the center had relocated under the heavy confection to the east if that’s the case, will that change future forecast tracks?

[underthwx]

The 5 am NHC update states that 97L remains poorly organized atm.....if the system takes longer to form a true center....do anyone yall feel that a center may form more eastward?....resulting in the system tracking almost entirely northward...over the Florida peninsula?....or maybe a center tries to form closer to Cuba?....resulting in track adjustments further east?....it just seems plausible to me....based on 97Ls satellite appearance....and reading the NHC update....thanks for any help with this....