Windspeed

It's the TC the GFS evolves out of 91L.

There are several natural catalysts that can explain the Younger Dryas though. We do not have a natural catalyst for the ongoing rapid changes we are seeing at present. I am impressed that you referenced it. I love reading about all the potential hypothesis and some which have been presented in journals as corresponding theory. Was it an impact event? Rapid glacial rebound due to a swift decrease in salinity? Volcanic fallout? Aliens? (joking).. At any rate, current changes are none of these. Well maybe it's aliens. Edit: I might also add that the Younger Dryas still took several thousand years to unfold, not ~200. What occurred then is still noteworthy compared to gradual change, but compared to the recent history is still a much longer drawn out period of change. We are seeing unprecedented changes unfolding at present, compared even to interglacial spikes and glacial spikes. Also, rapid changes are cold spikes after a long duration warming trend due to a natural catalyst. We are swinging warm rapidly at present without a natural catalyst. This may be jumping way off topic even for a banter thread about anything/everything, but it was referenced above for the tropical landfall event. I digress...

Oh man, Larry is checking all my boxes here: • Cape Verde Hurricane [emoji736] • Minimal land threat [emoji736] • Major Hurricane Status [emoji736] • Rapid Intensification [emoji736] • Large eye [emoji736] • Annular characteristics [emoji736] • Daylight hours (visible satellite presentation) [emoji736] Yes, I am a weenie. [emoji894]

Note that I stated "anthropogenic"; that was for a reason. Clearly climates change over time, but very slowly and on the geological scale of ages such a glacial and interglacial periods. These are also forced by introductions of gases or particulates into the atmosphere via a natural process (volcanic activity or rising/sinking crust), continental movements via plate tectonics and changes in shallow marine environments, or a slight change in a solar output via our closest star. These are gradual and we have geologic ages built around some of the major ones. That being said, macroclimates should not be rapidly changing within a few hundred years like a microclimate without some large scale global catalyst. There are no natural processes that can explain what we are measuring. Oh, except that pesky fact that human beings are wreaking havoc on the planet by both altering the surface and pumping 40 billion metric tons of carbon into the atmosphere per year; and that figure is still unfortunately rising each year that passes.

Recent satellite estimates support an upgrade to Category 3. The NHC's 00z best track analysis now shows 100 kts. Since we do not have recon data to overrule estimates, this is most likely the upgrade intensity on the next advisory package, 11PM AST. AL, 12, 2021090400, , BEST, 0, 152N, 427W, 100, 964, HU

Sunset over what is likely to be a major hurricane by morning. A large eye is clearing out as the Sun slips over the horizon.

That's the GFS developing the invest 91L in the SW GOM next week. It's certainly possible. Although I hope it doesn't resolve anything close to LA. They certainly don't need any kind of TC right now, even the weak TS variety.

Ida, though not as intense a hurricane, reminded me a lot of Camille in both track and extreme inland flooding far away from landfall. Sometimes these TC setups over the ECONUS can lead to much greater loss of life than the initial impact at landfall.

After Larry, long range EPS guidance is suggestive of a pattern more susceptible to AEWs or resultant TCs being steered further into the WATL and Caribbean. If this pattern evolves, mid-Sept into October might not only be active with a favorable MJO, but with increased probabilities of land interaction. Something to watch.

Larry looks healthy today. Good convective bursting and a cirrus covered eye that is notably larger than yesterday (Thursday) at this time. Should be a major hurricane over night or on Saturday. Time to pump up the ACE. I still feel a bit uneasy about Bermuda. This may still be a strong hurricane that just misses to the east. But a little stronger Azores ridging could get the island into the core. We've still got the weekend to iron out modeling and any potential downstream impacts there. Edit: I originally typed Friday above but in my head I was thinking Saturday for major hurricane status, if not over night, though certainly that wouldn't be impossible by the 11 AST package if Larry continues to improve structurally over the next six hours. I digress, I originally meant Saturday.

Climate change is real. Too much scientific evidence to support that anthropogenic influences are leading to events being amplified. I was a skeptic for a while. However, let me stress that simply picking a single event on the whim and blaming climate change is unwise and not very scientific. Plenty of bad tropical cyclones made impacts prior to the onset of anthropogenic influence upon the atmosphere. If anything, blatant blaming this or that without regard dilutes the message without evidence to support claims. You cannot merely state that Ida would not have occurred without climate change and not be undermined by historical TC landfalls. It is possible or at least more believing that climate extremes may lead to more frequency or stronger systems now, but it's why scientists do research. But you cannot just wave a magic wand however and erase the similar events that occurred 100 years ago.

Yes. The cyclonic low is post-tropical, but still the same system. See: Sandy, Agnes, Hazel, etc.

Ida's remnant low is wreaking havoc on the Northeast this evening. The total of this event from LA to Maine is going to punch the top five costliest in US history.

Holy!!!! [emoji102]

Larry is far enough south in track right now on a westward heading that it doesn't appear thermodynamics are going to be much of an issue at its given rate of motion. It is currently moving over 27-28°C SSTs, and will be crossing over a region of 28°C SSTs soon. It has a fairly moist envelope. It also looks like the vigorous mid-level circulation is wrapping convection up pretty fast here. Larry looks to be steadily strengthening and may be a hurricane sooner than forecast. It might even pull off a large eye right out the gate. The last CV hurricanes I can remember forming a large stable eye early into hurricane intensity were Isabel and Igor.

Even though the cyclone is in its infancy, the circulation is quite large. I'd imagine Larry is going to be a large hurricane as has been hinted by modeling. A core has not developed yet but there are good banding features already in progress. Probably won't take long to form a core once deep convection becomes centralized.

Just for posterity..

Ida may end up remembered as much for its extensive widespread flooding over the central Appalachians and Mid-Atlantic region as its impacts on the Gulf Coast here in the coming days. The mesoscale models are pumping out some insanely high totals over a large region. Oh, and look here, me posting the NAM in a tropical thread; whereby, inland flooding from baroclinic influences upon a surface low and frontogenesis, which is more within its wheelhouse of intended usage. The HRRR is showing much the same as is the RAP. Hope these are just being way overdone. Otherwise, Ida isn't done with the news cycles anytime soon.

The intensity forecast is pretty aggressive for an initial advisory by the NHC. 80 kts by three days. 90 kts in five days. Likely due to the overwhelming intensification trends by the globals and ensemble clusters. Good chance Larry will be the next major hurricane barring some complete failure to structurally organize, and even with slow organization, it probably reaches major intensity beyond five days anyway.

With regards to land interaction, it is worth noting that the ECMWF has been trending further south in track guidance now into the medium range. This is why I would not immediately discount the system as only an ACE producer. Though it does remind me of 2020 Hurricane Teddy in its infancy stage (as far as recent CV-long trackers go), and certainly a close call with Bermuda comes to mind, or perhaps even a potential post-tropical interaction with far eastern Canada. At any rate, the pattern is still far enough downstream that it could evolve into a surprise here. The system could get left behind in the central Atlantic/MDR and we're still early enough in the year that pesky WATL 500 hPa dam could rebuild.

Smith is now breaking these down so it may be a little more convenient for some via Twitter.

Well piles of salt on that. Hypothetical surface trough that results in that GOM TC doesn't resolve until beyond 228 hrs out in an omega block pattern. Such patterns are chaotic and I wouldn't even bother giving much attention until it was at least something resolving in the medium range. If that block does occur though, it would keep the potential monster CV 'cane out in the Atlantic in a recurve, though Bermuda could still be threatened. Again though, those type of patterns are chaotic and could easily break down. It's early to mid September. I have little confidence such would persist unless we were in October/November.