ATL: HELENE - Models

[Steve]

Thanks LSU. Hosting sites are blocked at work so I can't upload. Appreciate you handling that. Down to 981 at 30 hours. Depending on specific track now that it's past the Yucatan will determine how low the pressure will get on this run. It's got the hot Gulf and a high aloft at 30 hours so there's no reason this couldn't deepen 20mb or even more in the remaining time. Oh 975 at 36 hours lifting up a little but not quite to Key West's latitude.

[lsuhurricane]

[DunedinDave]

ICON doesn’t seem to dig that trough down as much so I am thinking this may be more west than before.

[Steve]

42 hours 969 and located roughly 24.10 86.23 but showing an eastern component along with the north.

Gonna be close to the peninsula again on this run unless it hooks north.

42 hours
https://www.pivotalweather.com/model.ph ... slp&m=icon

[Steve]

ICON doesn’t seem to dig that trough down as much so I am thinking this may be more west than before.

Initially maybe. I'm running at Tropical view surface and 10m AGL winds. Looks like a decided hook east there about a half degree between hours 42 and 48.

[DunedinDave]

Looks to me like landfall around Horseshoe Beach. Isn't that the same place Idalia made landfall?

Landfall a little more north than before but still dangerously close to the west-central Fla coast.

[lsuhurricane]

Trough definitely holds back on this run.

[lsuhurricane]

ICON landfalls at 947 mb

[derpbynature]

ICON really wants to give Cedar Key a bad day. After the fires they just had there and all. Sad.

[CronkPSU]

ooof Jacksonville would take a big hit on that path and forward speed....would be tons of flooding on both coasts

[Ubuntwo]

12z ICON is the strongest yet with landfall at 947mb near Steinhatchee. Appears to be correcting west now, TB area no longer makes it into the eyewall.

[DunedinDave]

Obviously there will be changes but I think we're zeroing on an Idalia redux here. Maybe landfall in the exact same spot. But potentially 30mph stronger than Idalia and with water being thrown on a more saturated land compared to a year ago. If the pressure is in the 920s or 930s as it passes by Tampa and takes the ICON or GFS track, the storm surge along that coast is going to be insane.

[Steve]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

[StPeteMike]

Honestly, everyone along the west coast north of Port Charlotte should be on watch. Just for reference, a day before Idalia made landfall, the 06z on many of the models had landfall near Carrabelle on the other side of the Big Bend. That was just over 24 hours before she made landfall south of Perry.

So things can change in a day and we have two days for that to happen here.

[Nuno]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

What's interesting is the NHC track is now to the west of GFS and ICON, slightly west of Euro... must be seeing something in the midwest already.

[Beef Stew]

If a more easterly path like the Icon suggests were to pan out, the east coast from Jacksonville to Savannah could see some moderate surge damage as well as a significant tornado risk as well. While not ground zero, the impacts of Helene are going to be felt far from the Big Bend, and even more so if she becomes a category 4+ and maintains a robust structure through landfall.

[Steve]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

What's interesting is the NHC track is now to the west of GFS and ICON, slightly west of Euro... must be seeing something in the midwest already.

Yeah. You can see the big *** high coming down into the plains and then the little point to the east behind the front/flow where I think the cutoff is going to form.
https://www.tropicaltidbits.com/sat/sat ... uct=wv_mid

Here it is in RGB (water vapor CONUS)

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

[MetroMike]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

What's interesting is the NHC track is now to the west of GFS and ICON, slightly west of Euro... must be seeing something in the midwest already.

But on the same token the NHC noted they could end up shifting the entire guidance suite in future cycles

[BobHarlem]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

What's interesting is the NHC track is now to the west of GFS and ICON, slightly west of Euro... must be seeing something in the midwest already.

They are sticking to the TVCN, for better or worse.

[Steve]

I don't know how any of these models calculate their dynamics and how much historical data goes into them. ICON definitely like that east of track path. NAM 12km is still centered on Apalachee Bay which seems a bit more realistic though we aren't talking much distance here between the two.

https://www.tropicaltidbits.com/analysi ... 2412&fh=63

What's interesting is the NHC track is now to the west of GFS and ICON, slightly west of Euro... must be seeing something in the midwest already.

They are sticking to the TVCN, for better or worse.

Certainly a good call when there is uncertainty