WxWatcher007

Fantastic

I prefer a January 20 plug pull

Which is absolutely bananas. We’ll see if things pick up on the backside of the peak.

Definitely east and not for us. But like I said earlier there is a window with this early season troughing if things align right. Maybe next week with a boundary over the Gulf and SE.

With slim pickin's out there to analyze in the Atlantic, why not spend a few minutes on this newest lemon. I first posted about the potential here on August 29th (yes, with my peak season forecast in mortal danger I will throw up a whoop for identifying this lol) as the guidance was consistent in developing an area of low pressure or series of areas along a stalled frontal boundary. Normally we see these during the early or latter part of the season, but with greater EC troughing recently, a window of opportunity has opened. Yesterday, you could see a robust area of lower level vorticity along the boundary Today that vorticity has wrapped up into an area of low pressure along the boundary. This is not currently tropical for a few reasons. First and foremost, it's attached to a boundary. That means that the low is baroclinic, not tropical. Secondly, despite there being a low and convection nearby, the convection is getting blasted to the east by very strong shear. The result is the following: While the boundary-attached low is clearly able to generate convection, the shear is pushing the convection off in a way that currently prevents this from becoming independent of the boundary and sustaining the necessary convection over the center to begin the tropical genesis process. Over the next few days however, the guidance tries to at least get this low to intensify some, and that could be the window for it to acquire more tropical characteristics. I doubt given the shear that it'll be able to fully become tropical, but there will at the least be a non-tropical low that quickly develops off the East Coast as it moves into Nova Scotia this weekend, and it could acquire enough convection during the intensification phase to be counted as subtropical. For those that truly care about the meteorology of tropical genesis, this will be interesting to watch. I should also note...that with persistent troughing over the next week or so, this is unlikely to be our only area to monitor. The guidance is picking up on a second quick developing low offshore late this weekend and perhaps another further south sometime next week. These boundaries can spur seedlings that become NS, especially if they are further south like the long range Euro hints at today. Just something to be aware of.

If it has a chance, it has to be tagged, irrespective of the type of season its been--at the very least for mariners.

The area off the east coast is now tagged. The models have quick development but it’s an open question of whether it’ll get enough tropical characteristics to be subtropical.

It may not develop lol but I love it when I can tag something before the NHC Subtropical would be the way to go and not fully tropical given how much shear is in the area. 1. Northwestern Atlantic: A non-tropical area of low pressure located a few hundred miles east of North Carolina is producing disorganized showers and thunderstorms. This system could acquire some subtropical characteristics over the next few days as it moves north- northeastward, remaining offshore of the northeastern United States. Additional information on this system can be found in High Seas Forecasts issued by the National Weather Service. * Formation chance through 48 hours...low...10 percent. * Formation chance through 7 days...low...20 percent.

Lemon tagged by the NHC now

Only one option now

The signal for some area of low pressure to develop off the east coast has been across guidance for the better part of a week now…likely non-tropical or perhaps hybrid. I’ll readily admit I’m grasping for straws as the basin remains barren with the following comment, but there may be a window for some September hybrid lows with so many troughs and offshore boundaries showing up on the models in the next 7-10 days.

@weatherwiz Maybe a partial explanation for the quiet in the western portion of the basin too. Too much subsidence in the Gulf/western Atlantic…too much rising air over the African continent, particularly over the Sahara. This kind of early peak bust requires all the dominoes to fall too. Take a look at the thread as it has other years included.

This is a worthwhile read. That massive area of subsidence over the Gulf and western Atlantic may also be why the western half of the basin has been bereft of activity despite several opportunities—as we’re even seeing now with the Gulf disturbance we’ve been casually watching.

People are trying to do them now with 65-70% of the season to go so yes Don’t get me wrong it looks bad—historically bad—but it’s like canceling winter on December 31, which people do every year as we know lol.

I think that’s one of the reasons—seedlings that would otherwise mature are getting smothered by a combination of stable air profiles and cool SSTs to the north of the CV islands before getting anywhere. That said, even stuff that’s come off south and plodded along into the tropical Atlantic east of the Lesser Antilles has struggled mightily. So I don’t think that’s the only explanation. The ITCZ dropping south may be late for tropical Atlantic genesis which should suppress the NS number, but if an active WAM is going to allow the train of vigorous waves to continue into October, once they get to the Caribbean and western Atlantic where TC genesis is climatologically favored things may open up. We’re just so far into uncharted territory (no NS during this period since 1968) that idk if anyone knows what’ll happen. It’s incredibly fascinating to watch.

I’m not sure if it’s just a delayed signal that’ll get washed out on the EPS, but 12z was quite robust in the Gulf with the current Caribbean disturbance. Seems to pull it north or NE eventually too with the eastern U.S. trough next week.

Right. SSTs/OHC can tell you which side of the AN/BN coin to lean, but that only takes you so far. It’s shocking that with shear being low so often across the basin we’re as low as we are. I’ve been factoring in stability/SAL for a few years now and it just seems like every year it gets worse. It’s far from apples to apples but it reminds me of the great setups we get in winter and confluence to the north just grinds up what’d be a KU 95 times out of 100. Everything else is good as it gets from a broader seasonal perspective—but you can’t factor in this one persistent feature that kills potential in the cradle. It’s both maddening and fascinating. Pouring in the Sahara and puffy sand laden clouds in the tropical Atlantic.

Thanks. I’m dumbing down why it’s been historically quiet, but there are likely a series of factors that has made the season an increasingly epic dud thus far. The real interesting part is whether this continues into later September when we usually see climo shift west and warmth aloft diminish. I’m not ready to totally pull the plug. The late season storms we get in the western Atlantic could be absolute nukes with enough runway.

Agree—we’ve seen anomalously low shear in the basin all season. Cool neutral hasn’t hurt. It’s far more complicated than anyone can fully grasp I think. Quietest since 1968 when a few months ago a top 5 season looked like a lock? That doesn’t happen easily.

Tropical Update--September 3, 2024 Yikes Now that we're actually moving through the upswing of the climatological peak of the season, we're entering epic bust territory. Since Hurricane Ernesto early in August, there has been an intractable lid on the Atlantic. Not just the MDR, but the entire basin. We have held at 5/3/1, and while our ACE number is still above normal for this time of year due to the fast start and high end systems relative to the early part of the season, we've gone from historically active to historically...inactive. According to Dr. Phil Klotzbach, this is the first time since 1968 that we haven't had a named storm between August 13 and September 3. That's extraordinary. There is a lot of conversation happening in the tropical wx space about reasons for this. I'd argue that despite historically warm SST/OHC and anomalously low wind shear across the MDR most of the season, that a combination of stability, SAL, and in the last month or so, a much further north ITCZ leading to waves leaving Africa too far north to survive getting to even the central Atlantic has been the main culprit. It's possible that too wet a West African Monsoon is bad for TC genesis. Stability issues further west into the tropical Atlantic (the area between Africa and the Antilles) has stifled everything that has tried to develop there in essentially the last month. Even now, it's not a good look in the tropical Atlantic. For my peak season forecast of 15/10/5, we need to get on the board soon. The reason to not completely pull the plug on higher end activity in terms of H and MH is two fold. 1) Despite the iron lid being over the basin, the underlying factors for a quality over quantity season still remain Simply put, the lack of instability in the eastern MDR to this extreme once again makes me believe that truly significant activity here is a lost cause. However, just west, with a combination of lower shear (especially as the trade wind impact diminishes with climo) and historically high OHC and much more normal instability, I do think that a lot can happen through later September and October. 2) Even though it's September 3, approximately 65-70% of historical activity in a given season still remains. The favorable conditions above should be able to take center stage as climatology abandons the tropical Atlantic and the focus for TC genesis becomes the western Atlantic and Caribbean. We'll see if they do. Areas of Interest The basin is still hostile, but the chance of development is there for any one of these. The NHC notes three areas and I add a fourth. 1. Caribbean Disturbance--60% This is the one we've been following for a while, and the signal has continued to waffle on the models. Unlike in the tropical Atlantic, this one has been firing more convection in the Caribbean (speaking to greater instability) but ran into the problem of shear and becoming more strung out as it quickly moved west. It's just south of the island of Hispaniola right now, and while it barely has visible signs of life I would not count this one out yet. The ensemble signal is still modest, and with a more favorable environment likely as it gets into the western Caribbean or potentially Bay of Campeche, it's worth watching. 2. Eastern Atlantic Wave--40% All the way near the Cabo Verde Islands we have a strong wave that's a bit tied up in the currently further south ITCZ/monsoon trough. The model signal is modest but I need to see that something can develop this far east to believe it given the profound stability issues. 3. Central Atlantic Wave--30% The third area on my list has only really started grabbing attention in the last 24 hours, in large part because it has for now been able to maintain persistent convection. If you refer back to the SAL/water vapor image at the beginning of this post, you'll see that there's a lot of dry air lurking. I'm less bullish on this one as well because there's no evidence yet of robust low level vorticity. Yet at least. This wave only has a few days before conditions become even more hostile, but if it can keep convection firing that may be enough time for a quick spin up before getting ripped apart. Low odds at this time. 4. East Coast Hybrid--10% Finally, the lowest odds of development come from something not even tagged by the NHC. The signal for some type of low pressure to form off of an offshore boundary has been persistent for a week now, and the guidance continues to try to spin something up along the boundary in the coming days. If you look at the vorticity image above, it's easy to see why. The question however, is how far south does something develop, and can it attain tropical characteristics. Most indications are that it's more baroclinic than tropical or subtropical, which makes sense given the trough and fact that anything tropical trying to develop would get blasted by shear, but something hybrid may be worth keeping a casual eye on.

Low of 46.5°

892mb at landfall too, and it was a slow mover. Just insane.

Not related to New England, but this one is one of the all time greats. Going 1 to 5 that close to FL is incredible.