Windspeed

Polo is undergoing an EWRC. The inner eye is shrinking rapidly. The concentric outer eyewall appears to be taking off, and convection remains intense. Though, due to the chaotic nature of these processes, it's futile to try and forecast how fast these will complete and the larger eye clear out entirely, but this one may not take very long. I am basing this on the intensity of convection that persists and the symmetrical structure of the CDO. Once the outer eyewall is fully dominant, it shouldn't take long for sinking airmass to suppress remnant convection of the old and clear it out. SSTs are still very warm, though OHC at depth is decreasing. Polo's motion seems fast enough that upwelling shouldn't be much of an issue for now. SSTs do drop off in the forecast when Polo is moving poleward, which will bring down intensity regardless. Southwesterly shear should also begin to increase, which may help get some drier airmass into the core and put an end to its many hours of Cat 5/upper Cat 4 durations of intensity. Polo may be able to maintain Cat 3 status into the Baja Peninsula. We are still several days away from that, however.

Polo might be making another run at sub 900 mb. This satellite presentation speaks for itself with intense lightning data around the eyewall.

Nolo appears to be wrapping convection around the eye now and trying to mix out some dry airmass. We'll see just how strong it can get prior to the closest approach of the Big Island.

Fay looks like it is going to run out of time again. Clearly, the dry environment is causing issues and inhibiting core development. Increasing shear will start impacting the system by this afternoon.

Polo is still putting on a show once again. The eye has warmed and the CDO has cooled. It probably will regain Category 5 intensity on the next update.

It's worth noting that the 12z HAFS suites get Fay down to 989 and 983 mb respectably by noon tomorrow before shear begins to increase again. Fay's vortex is embedded within a high background pressure regime of 1022+ hPa surface isobar with a 1030 hPa surface ridge centered to the north and 591dm heights. For it to drop 20 mb by tomorrow would require some rather significant intensification, and Fay would absolutely be a hurricane if this unfolds. Again, it's TC modeling, and HAFS may be overdone, but Fay has a real shot if it can continue mustering up convection and close off a core this evening.

Not only has Fay come back from the dead, for now, at least, a small ULAC has positoned right over top of the system. Shear has dropped significantly. The TC is embedded in a rather dry environment. As the NHC noted in their discussion, this may prevent any significant intensification. Despite the less than ideal moisture environment, convection has managed to blossom this morning. Might we get a surprise? It has an established vortex and 36-48 hours to play with before shear reinvades.

FWIW, the GFS operational has brought back a CAG system in the midrange, lifting it into the GOM the past few runs. The 00z was more pronounced with a hurricane.

We're several days away. The important thing to note from satellite is that there is a surface trough with regions of spin. Some of that energy may even split off to the east. But a surface low will eventually organize, intensify and move near the Mid-Atlantic or New England. It's a bit chaotic between operational runs right now because we're dealing with a phasing situation in 48-72 hrs. Also, you know how tell the season is dead? When the entire discussion has been taken over by a potential mid-latitudinal coastal storm in the main tropical thread.

Here is the surface trough, and you can see the spin on visible. But this feature will eventually phase with the mid-level level low that dives out of the Ohio Valley and off the coast of VA/NC. The resultant low is what evolves into our coast storm in about 48-72 hours.

Polo has some structural changes occurring. Note the two images below. Over the past four hours, the tops are warming around the immediate eye, while a larger / thicker band is expanding out away from the immediate core. The MW scan from earlier today did show some intense banding. Though it would be impressive how quickly that has come to evolve into a concentric feature. However, look at your post. That does appear to be evolving fast on recon's radar. Granted, Polo's eye has been small, and at this intensity, structural changes may evolve rapidly:

889.2 mb EXTRAP ... Wow!

FYI, here is the most recent OHC map from Rosenstiel. Polo is currently positioned over a deep, warm eddy. The 26° isotherm is around 70-80 meters (250 ft) in depth.

It depends on the duration of slow movement. The slowdown / stall is occurring now. But heat content is deep there. Sure, it could limit peak intensity down, somewhat, given enough time. Forward progress is forecast to take the core NW tomorrow. But I really think internal restructuring via an EWRC would impact its peak prior to mixing on Wednesday. The 30-31° isotherm layer is not shallow and some of the deepest on the globe right now due to El Niño. The 26° isotherm is over 250 ft. If any location can support a stall right now, it's there.

Looks good for today. But you will notice those are some intense outer bands. I'd say a concentric eyewall will most likely develop by tomorrow given that banding structure.