Windspeed

Dr Papin mentioned this in his latest post. The same PV helping to lift 99L's resultant TC into the central GOM also seems to act as a buffer between airmass evacuation from the potential EPAC system and the same from the GOM system. At any rate, the overall upper environment looks considerably conducive for an intensifying hurricane, especially given the westerly + northerly branch outflow jets.

Uh oh...

That's a big if though. Early genesis in the NW Caribbean could open the door for the TC to be anywhere along the north GOM, not necessarily a Laura redo. Note how the PV anomaly north of 99L evolves through the first 72 hours. If 99L's resultant TC deepens faster than the GFS models here, a stronger stacked system is likely to feel the initial poleward 500-300 mb flow over the eastern GOM until the TC's diabetic heat transfer processes squash it. This could result in more intial latitude gain until a gradual bend back NW with increasing 500 dm heights over the eastern CONUS. Lots of possibilities here with a notable heavy flood threat in a stalling inland deluge with a possible block scenario late next week into the following weekend. This is unfortunately another nasty setup for inland flooding.

Heh, 99L does not appear to be wasting any time getting organized today. Note the sharpening of the wave axis and evident mid level circulation developing. If these trends continue, location of low level vortex / TCG is going to be sooner ahead of schedule than yet modeled. This would give credence to more northerly clusters of track ensembles, but of course still all unknowns until we have a CoC to track and better model initializations.

So boring yet you'll be posting nonetheless, right? lol

Worst time of year for any TC to reach the northern GOM regardless of gulf loop current position and eddy proximity. The entirety of the northern coast from Texas to the Florida Panhandle is ≥30°C; its profile extending several hundred miles out from shoreline with a very large surface area in the western GOM. A slow moving or stalled system can still upwell and lower its maximum potential intensity, but from the highest of known intensity potential here. Even a large TC with decent motion is only limited by the atmospheric environment which it is contained, interaction with airmass, structure, shear, etc.. Thermodynamic profiles such as these are essentially overkill this time of year until we start seeing cold fronts reach the GOM in late September/October, or numerous TCs decrease heat content. That being said, even a slow moving large TC could stall over the central GOM for several days and likely still remain a major hurricane if under a favorable atmospheric environment. The gulf loop current extends all the way up to the Mississippi River's discharge current at present. So there is a very a deep 26°C isotherm from the Yucatán Channel up to the shallow shelf waters near Louisiana. Really the entire GOM has good depth of heat content, but obviously that absurd loop current profile is like the NW Caribbean.

We're in the medium range now. It's becoming very apparent that the upper level pattern will most likely be primed to support a hurricane in the GOM. The question is the latitude where low level circulation closes off. Obviously a lower latitude will spend more time over the Yucatán and will have a longer organizational period of development versus a more northern region of TCG. This matters for if we are looking at a potential major Harvey-like hurricane or something more slow to intensify into landfall. Nothing is in stone until we have that vortex placement regardless of all the crazy outputs we may yet see from the models. That being said, the signal is clearly on the up that we have a TC in the GOM next week. You do a double-take at these outflow patterns in the 72 to 126 hour range.

While we're all going to be looking to the NW Caribbean and GOM for potential development into the weekend, currently there is a nice AEW south of the Cabo Verdes forecast to make its way across the MDR this week. It's not in a horrible environment at the moment, but conditions are only marginal across the MDR. Some SAL and stable air mass to contend, but it bears watching.

Linda is a sheared cyclone, no doubt. But how on Earth is that not a classified TC? It has a closed low level vortex and ASCAT has TS and Gale force winds. Also, Linda has produced nice bursts of convection over the LLC the past 24 hours. Boggles the mind...

This thread.. and I absolutely agree with it. What the hell has the CPHC been doing the past 24 hours?

Yeah NYC and areas just north are in the pivot of a nasty band.

Grace's remnant surface trough is redeveloping into a cyclone SSE of Cabo San Lucas. Explosive convection is persistent and likely to regenerate a closed vortex at this rate. This will get a new name if reaches TS strength even though Grace is the source of the disturbance. Per WMO rules, a tropical system must remain classified between basins to retain its original name.

NOAA2 is en route so we should get a sampling of Henri despite the earlier AF Hurricane Hunter abort.

New England regional subforum has the hot thread. Makes sense since that is where it will be making landfall and the forum kind of rose out of the ashes of EasternWx. The tropical subforum threads are hotter when its a purely tropical and subtropical latitude event. This system isn't exactly going to make people "OMG!!" at any point from an intense hurricane aspect, outside of some kind of unforeseen atmospheric phenomenon. I should clarify Henri is still a dangerous threat, but more from a hydrological event. A Gloria or '38 it aint. Edit: Now watch since I made a that snooty insulting comment about Henri above, it drops 20 milibars over the next 6 hours.

I realize this thread is being neglected somewhat with several busy regional (PA/NY/Mid-Atlantic/NE) forums with a landfalling Henri. At any rate, Henri is now Hurricane Henri. The third Atlantic hurricane and the first time since 2012 to have three this early. Kind of a surprising stat on the latter there as we've had some busy seasons since 2012.

6z GFS does keep a fairly steady motion into landfall. The distance between 6 hr positons doesn't decrease too much until Grace is inland. Still, that is at least 12 hours over decreasing thermodynamic support. I'm not sure how much baroclinic influence the binary interaction could give during that time for convective support to mix down 700-850 hPa level winds. Could surprise but obviously the biggest threat is flooding, which has been and should continue to be overstated.