ATL: OPHELIA - Post-Tropical - Discussion

[syfr]

I see no reason why this cannot intensify into a hurricane..

It certainly could, but the water is getting cooler as she nears the coast, and interaction with land isn't going to help it much.

[ElectricStorm]

Looks like 983.6 extrap this pass

[JRD]

Surface analysis shows that the troughs have disappeared and the warm front is no longer connected to the core but is still very close to it.

[ElectricStorm]

Eye drop supports 984mb so still deepening

[USTropics]

It's asymmetric for sure, but the biggest distinction on why this is classified as a tropical storm (and not subtropical or extratropical) is that Ophelia has taken on the properties of a warm core system:


Looking at model analysis and theta-e values (essentially this is potential temperature at SLP if you were to condense all of the moisture out), this gives a good picture of total available energy in the atmosphere as well as where the warm, moist air is available to fuel the storm's development and intensification:


You can do a vertical profile of the temperatures at various levels to also see this is now a warm core system (using the 12z ECMWF operational analysis):
850mb (lower levels):


500mb (upper levels):


While Ophelia had hybrid characteristics, the main driving force is now latent heat (associated with the Gulf Stream) and not baroclinic processes (which we had yesterday/earlier today with the frontal characteristics). If you overlay track with current SSTS, we can see this is the case as well:


One last note, the displacement of convection is a byproduct of what helped initialize this low pressure. We've had this amplified subtropical jet that has extended all of the way towards Florida at the upper-levels, and this has developed a negatively tilted trough (highlighted below). While this has displaced the main convection, a negatively tilted trough typically enhances vertical shear (which is why we have +convective activity):

[JRD]

The storm, in addition to being slightly asymmetric, has a shallow warm core bordering on moderate warm core.

[Sciencerocks]

[Vdogg]

https://imagizer.imageshack.com/img922/3165/1LvMZ5.gif

I'd be shocked if this isn't a hurricane...

[sponger]

So a hurricane watch was issued at 5pm? The NHC graphics did not show that.

https://www.nhc.noaa.gov/refresh/graphics_at1+shtml/234950.shtml?radii#contents

[WalterWhite]

https://imagizer.imageshack.com/img922/3165/1LvMZ5.gif

I'd be shocked if this isn't a hurricane...

The NHC has kept it at 60 kt for the 8:00 PM EDT update.

[tolakram]

saved radar loop

[Vdogg]

https://imagizer.imageshack.com/img922/3165/1LvMZ5.gif

I'd be shocked if this isn't a hurricane...

The NHC has kept it at 60 kt for the 8:00 PM EDT update.

I just saw that. Recon seemed to be higher but perhaps they're being conservative.

[Vdogg]

Winds picking up decently in Norfolk/VA. Beach. 36 mph sustained with 51 mph gusts

[invest man]

I'd be shocked if this isn't a hurricane...

The NHC has kept it at 60 kt for the 8:00 PM EDT update.

I just saw that. Recon seemed to be higher but perhaps they're being conservative.

Wonder if they will have a special statement to announce Hurricane before 11 if they get data to show that? In reality wouldn’t make that much difference at this point.

[Hammy]

https://imagizer.imageshack.com/img922/3165/1LvMZ5.gif

I'd be shocked if this isn't a hurricane...

The NHC has kept it at 60 kt for the 8:00 PM EDT update.

More than likely didn't want to change the intensity while there's no plane out there, since I believe we'll have one in time for 11.

[mitchell]

Frying Pan Shoals buoy sustained 43kts gusts to 61 kts.

[floridasun]

i think it be hurr by 11pm or 5am

[SouthernBreeze]

Earlier today, tracks were going over New Bern NC, now I see updated ones inching W to almost Jacksonville NC

[mitchell]

Earlier today, tracks were going over New Bern NC, now I see updated ones inching W to almost Jacksonville NC

This morning's GFS vs evening. Both images are for Saturday Midday. Looks like shift west and weaker.

[Vdogg]

Oceanfront is wild rn. Definitely at the higher end of tropical storms. Probably getting close to 50 sustained now. Just closed down the street on my route home due to downed power line.