ATL: HELENE - Post-Tropical - Discussion

[Pipelines182]

Unless the center is in a different spot, it does look to be moving due north.

Having Ian flashbacks here because I remember distinctly it was supposed to move NW off the western tip of Cuba and it made that north turn early and I remember talking here about it on here and how it actually hit the western side of the Isle of Youth when it wasn't supposed to. The Isle wasn't even in the cone 24 hours before it got hit. And then after it crossed Cuba that NE turn way earlier than any model thought it was and then again, the models had to shift.

Storms coming from this area can be very tricky and do what they want to do. Not saying this will but just be watchful.

Hard to tell right now with the center obscured. Shear is pushing the convection north so it can make it look like that's where the system is going when it's not. With the center maturing, motion can be a bit erratic, but the motion should be generally in the NW direction.

At this point it is not shear, it is the steering winds around 500mb. The ULL has retrograded and weakened to the point where it is not shearing the system but ventilating it.

The winds at 500mb are at a different direction than the winds at 850mb, isn't that what shear is? It looks like shear has pretty much relaxed on the south half, but there's still some on the northern half.



10-20kts on the north side still, but steadly dropping

[LandoWill]

They seem pretty confident with predicting the panhandle/big bend area as landfall.(no warnings for tampa coast) I'm expecting where I'm on the west coast, north of Tampa to probably get winds equal to what we get after a cold front comes by, so i don't think I'll be doing much more than unless something changes tomorrow. Luckily i do live a little further inland from the beach.

[sponger]

Convection is now wrapping around the center. It is likely stacked and ready to go.

[grapealcoholic]

it’s 30 degrees now. LLC still moving mostly north

The center was east of the buoy a few hours ago.
Surface pressure down to 996 mb but there are still transitory light winds near or in the center.
Shift to 30 degrees means the LLC is still south of the buoy location

30 degrees winds does not mean is south of the buoy

Edit: Now winds are north at 20 degrees. The LLC is east of buoy.

Directly east would mean 0 degrees. Just slightly south

[Zonacane]

The center of Helene is going to get pulled north by that blowup. Any deviations north/east away from the Yucatán will spell disaster for Helen’s intensity in the Gulf

[ColdMiser123]

HAFS-A/HAFS-B were too far west by about a half degree longitude at 5 pm EDT. Likely too far west into the Yucatan based off that short-term motion.

[3090]

NHC says 115 at landfall.

[Travorum]

This really is a massive storm.

Shear has definitely relaxed in the past six hours. Good outflow is now setting up on all quadrants. Just needs to fill in the center a bit and it's off to the races.

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

It's starting to get that look

[WaveBreaking]

What scares me about Helene is if it builds a small core like some of the hurricane models were suggesting, then it could very quickly kick off an RI episode like other hurricanes with pinhole eyes have done in recent memory (Idalia, Maria, etc.). But at the same time, that would also increase the chances of a prolonged EWRC which would prematurely halt its intensification. No matter the size of the core, these next few days are not going to be pretty regardless of what happens (unless some sudden, under-modeled mid-level shear shows up and disrupts the core).

[Sunnydays]

If she's able to thread the needle and miss the Yucatan, This is going to be a scary situation. Everyone please take care.

[galaxy401]

Helene is really looking better and I can certainly notice banding as well. Expect the worst from this storm and hope for the best is what I feel the mindset should be.

[ColdMiser123]

Buoy 42056 is now down to 995.5 mb at 5 pm EDT - some steep pressure falls are currently ongoing.

[Nimbus]

The center was east of the buoy a few hours ago.
Surface pressure down to 996 mb but there are still transitory light winds near or in the center.
Shift to 30 degrees means the LLC is still south of the buoy location

30 degrees winds does not mean is south of the buoy

Edit: Now winds are north at 20 degrees. The LLC is east of buoy.

Directly east would mean 0 degrees. Just slightly south

The winds are coming from just east of north they probably will flip to southwest if the storm passes directly over, but if the storm passes further east then they will come from the northwest between 270 and 360.

995 pressure and back to 40 degrees

[Michele B]

I am curious about the placement of warnings. It seems like the TS warning/Hurricane watch combo is a good option for much of the Florida west coast since the track is pretty far offshore and the Hurricane winds probs are low....so far..

We are not in a coastal county (east of Sarasota), but have been put on Tropical Storm watch since this morning.

I expect lots of rain, and some wind.

But what I am most NOT looking forward to is the never-ending tornado warnings that go off all night (like they did during Debby).

[SoupBone]

They seem pretty confident with predicting the panhandle/big bend area as landfall.(no warnings for tampa coast) I'm expecting where I'm on the west coast, north of Tampa to probably get winds equal to what we get after a cold front comes by, so i don't think I'll be doing much more than unless something changes tomorrow. Luckily i do live a little further inland from the beach.

There were warnings in the previous discussion that additional changes in landfall could occur, depending upon how she's moving. To me, that's a sign that they are at least acknowledging that this might track further east and down the coastline of Florida.

[Michele B]

[url]https://i.postimg.cc/3rfJ3Bt1/43eb7fc7-1cc8-417b-94e0-a4163e9ee43d.gif [/url]

12z GFS had the LLC bounce south then north in the next 18 hours at @85.6. It's occurring now a full degree E at @84.6. Maybe this very small eddy/LLC is rotating around a larger broader circulation, but if this is what the models are tracking it's occurring a full degree east than modeled.

It might not go over the tip there on Western Cuba, but I think it will get close and defy many of the models that show Helene closer to Yucatán or even going over.

Once she fills that naked swirl, it’s off to the races unfortunately.

From a size perspective, this is going to be a big girl, isn't it? Sure has the makings of that. Hopefully it doesn't get to the size that Wilma was. That thing was one of the biggest monsters I ever saw. Gilbert was another. Let's hope we don't see that here.

I think that's what we will experience, Dave. I think your county is also under Tropical Storm watch. I think because this thing is huge and there will lots of effects because of it: rain, some wind gusts, but mostly tornadic activity coming ashore. That's the part I hate the worst!

[Zonacane]

Buoy 42056 is now down to 995.5 mb at 5 pm EDT - some steep pressure falls are currently ongoing.

.01 in every 10 minutes. Going to be a hurricane soon.

[xironman]

I'm back from some meetings today. Models are all over the place, but let's focus on the storm itself in this thread and she's looking good. Shear is rapidly dropping. It was near 30 kt only 8 hours ago and already fell to 12 kt 2 hours ago (18z). The current 3-hour based shear tendency near Helene is around -30 kt/day. 12z GFS even predicts shear to drop to ~5 kt by 00z. On IR it looks like pink cloudtops are forcing their way around the northern half of Helene's center. The main potential issue for Helene is land interaction with Yucatan, because of course that could destroy even the most potent storms. But it if avoids that (like 18z ICON is showing) I think she's off to the races.

Every latest obs show she going to shoot the channel just like the NHC says

[NDG]

Buoy now reporting a pressure of 995mb with 17 knot winds, pressure is probably down another mb or two.

[fllawyer]

They seem pretty confident with predicting the panhandle/big bend area as landfall.(no warnings for tampa coast) I'm expecting where I'm on the west coast, north of Tampa to probably get winds equal to what we get after a cold front comes by, so i don't think I'll be doing much more than unless something changes tomorrow. Luckily i do live a little further inland from the beach.

There were warnings in the previous discussion that additional changes in landfall could occur, depending upon how she's moving. To me, that's a sign that they are at least acknowledging that this might track further east and down the coastline of Florida.

Yes, but if that was the case, wouldn't you expect them to keep those caveats in the 5pm disco? Seems they dropped it. Plus the absence of a hurricane warning for Pinellas/Tampa Bay Area seems like a rather deliberate choice. Seems like they have more confidence.