Atlantic tropical wave continues to be worth watching for the islands as it slowly tries to get together

In brief: The tropical wave in the eastern Atlantic continues to slowly consolidate. Development odds remain elevated over the next week, but there’s a pretty significant difference between most ensemble guidance and operational guidance versus yesterday that raises some questions. Worth continuing to monitor in the islands.

East Atlantic tropical wave

Another day, another update on the tropical wave we’ve been discussing since last week that’s still at least a couple days from even developing.

The tropical wave looks a little more consolidated compared to 24 hours ago, but it’s still not even at Invest stage yet. (Weathernerds.org)

The wave looks marginally better than it did 24 hours ago; it’s a little more consolidated at least. But it remains far from really *doing* anything yet. I imagine it will approach Invest level by tonight or tomorrow, as models show further consolidation of the disturbance up around 10,000 feet altitude. All that said, my impression of the ensemble modeling this morning is that support has actually dropped a bit with respect to development. Fewer European ensemble members are developing the system, fewer of the Google Deep Mind AI ensemble members are doing so also. In other words, ensemble model support for this, broadly, seems to be stagnating. The NHC odds remain at 70 percent, and that seems fair for now.

About 30 to 40 percent fewer ensemble members than a day ago have this wave developing by Friday night in the central Atlantic. (Google Weather Lab)

I emphasize the ensemble modeling above. Interestingly, if you look at last night’s European operational model, it actually does show it developing and developing aggressively too. Other operational models do too, the GFS less so, the ICON more so. We often preach not to pay much mind to the operational model guidance, and in this case it would also be wise to be skeptical. If you look at the current 5-day out forecast from the European operational model over the last several days, you can see how the model has waxed and waned.

The last several days of European model runs show varying solutions, placements, and intensities of the tropical wave east of the islands at day 5 (Sunday night). (Tropical Tidbits)

There’s a chance here that this is a smaller storm (the Euro solution in particular reminds me of what we’d call a “microcane,” or an especially small hurricane) and the higher resolution operational models are going to be more apt to “see” intensification happening rather than the AI ensembles. In my experience, storms like that have a window to do what the operational modeling says they’ll do. And if they miss the window, you can forget development. I really think this one is a tricky call. Kind of a fascinating case meteorologically too. We’ll know in a couple days whether this is a legitimate concern for the islands, but for now it makes sense to just check in each day for the latest.

Beyond the islands, it seems this gets picked up and absorbed by a trough off the East Coast. But it’s too early to speculate too much there. Right now, we just need to figure out whether this thing can even get off the ground.

Going to cut it a bit short today with a pretty full schedule today. But there isn’t much else of note in the tropics at least. More tomorrow!

Atlantic development will proceed rather slowly this week, while a Pacific system may deliver rain to the Desert Southwest

In brief: While it’s too early to say anything with a lot of confidence regarding the disturbance in the Atlantic, we think it will slowly crawl west this week and perhaps approach the islands by early next week. We explain what we know. Plus, the Desert Southwest may get some beneficial rain courtesy of the latest Pacific tropical depression!

Tropical Atlantic disturbance

The odds continue to increase that the wave off Africa will develop over the coming days. The National Hurricane Center is up to 70 percent odds today for the next 7 days.

The development region over the next 7 days extends to just east of the islands. (NOAA NHC)

This system is still about 7 to 8 days away from making it to the islands if the models are to be believed. This one seems to be getting its act together at a much slower pace than feels usual. Whatever the case, thunderstorms are ongoing west of the tropical wave itself. Over the next 36 hours or so, expect the whole broad area to gradually consolidate into something a little more focused southwest of the Cabo Verde Islands.

While the tropical wave itself is located just south of the Cabo Verde Islands, most of the thunderstorms are west of the wave. It will take a good 36 to 48 hours to consolidate into something that can possibly develop. (Weathernerds.org)

Given the current situation with thunderstorms well to the west of the wave itself, you can see that beyond “there may be a good chance of development,” much is uncertain right now. What we can say is that by Thursday morning, we should have some nascent organization ongoing, probably something like an Invest to the west-southwest of the Cabo Verde Islands.

Various Euro ensembles and AI models show some very nascent organization happening with decent agreement to the WSW of the Cabo Verde Islands by Thursday. (Google Weather Lab)

Where models can’t quite agree is at what longitude exactly this occurs. There’s a solid 6 to 7 degree spread in longitude for where this is as close as Thursday morning. This will obviously have ripple effects on whatever comes next. But rather than just throw up our hands, let’s talk about what should be happening as this comes west. Let’s assume by Saturday we have an organizing disturbance around 40 degrees longitude.

The overall setup on Saturday favors an east to west moving disturbance under Bermuda high pressure. (Tropical Tidbits)

This seems to suggest that the islands should probably keep an eye on this disturbance. Any organization is probably going to be sluggish here, as there are other hurdles this still has to encounter and overcome. But I think what we can say through the weekend is that a westward moving tropical disturbance may begin to slowly develop as it approaches the Caribbean islands.

Beyond that? There I will shrug. In theory, the high near Bermuda is expected to strengthen and shift just a tiny bit east. With a lingering trough over the East Coast, this should allow it to begin gaining latitude at some point early next week. But going out from there, I don’t want to speculate on what may or may not happen. At this point in time, it’s not a realistic threat to land, but it is worth monitoring through the week for the Caribbean islands. For the U.S., you can revisit this again in a couple days. We are a long, long way out still.

After this wave, I’m sure we’ll get another, but admittedly, the next 7 to 10 days look pretty mild across the Atlantic basin other than this one disturbance.

TD 12-E in the Pacific a rainfall maker for the Southwest?

Shifting into the Pacific basin for a moment, Tropical Depression 12-E has formed, and it would appear that this will make it toward Baja by Friday, probably as a tropical storm.

TD 12-E in the Pacific is likely to make it to Baja by the weekend as at least a tropical storm. (NOAA NHC)

There is a chance that this system will push hurricane intensity. But 12-E (or what should be named Lorena) will probably be notable for its moisture. Additional moisture should pivot into the Southwest this week. This will allow for an uptick of (mostly) beneficial rains in the Southwest.

(NWS Tucson)

Details will still need to be sorted out, but this seems like a good setup for a tropical moisture plume to be stretched north toward Arizona and New Mexico. I would anticipate heavy rain chances, at least in scattered locations by the weekend. Indeed, the rainfall forecast for southern Arizona and even northern parts of the state is pretty lucrative over the next 7 days.

The initial 7-day rainfall forecast for Arizona and western New Mexico is pretty healthy. (Pivotal Weather)

Some of the rain near the border with Mexico does fall over the next few days. Anticipate some further adjustments in the overall rain forecast for Arizona and New Mexico as we get closer to the weekend.

Labor Day is trouble-free in the tropics, as we take a look at what is to come over the next week or so

In brief: We’re in the peak weeks of hurricane season in the Atlantic now. Thankfully there are no serious concerns on the radar for the next week or so. We discuss the setup and pattern, as well take a look at some other odds and ends of note today.

Thanks for indulging us in a couple days off this weekend, as we rest up for the final marathon stretch of hurricane season between now and October. From an accumulated cyclone energy standpoint, the next month and a half accounts for about half of the hurricane season’s average total on average.

Where do we look for tropical storms and hurricanes to originate in the first 10 days of September? Everywhere. (NOAA NHC)

This time of year, tropical systems can form basically anywhere in the Atlantic Basin. The Gulf? Yep. The Caribbean? Sort of, but yes. The southwest Atlantic? You bet. Between Africa and the islands in the MDR? Oh yes. Basically, we’re watching everything in early September.

Today’s satellite image shows a couple stand out areas of note.

A couple areas to watch, though none are serious threats at this time. (College of DuPage)

First, closer to home, there is a cool front draped across the Gulf this morning, an oddity for this time of year but not unheard of.

A cool front draped across the Gulf and Florida may fire up some thunderstorms that could have a low-end chance of tropical development as they move east into the Atlantic later this week. (NOAA WPC)

There will be showers and thunderstorms that fire up near or north of that frontal boundary that may work their way into the eastern Gulf or toward Florida. As the week progresses and the front dissipates, it’s not out of the question that one of these thunderstorm clusters acquires a low probability of development. Its track would quickly scoot into the Atlantic from the Gulf, reducing both any time over water, as well as any real land impact concerns. Basically, nothing is expected, but don’t be shocked if you see an area of interest pop up in this region briefly. This weather pattern is actually important in the medium range, however, as just a boatload of dry air is going to be deposited into the Gulf thanks to this early season front and another this weekend and next week.

Substantially dry air this week and again later next week may inhibit any possible development or maintenance of any tropical disturbances in the Gulf or off the Southeast coast. (Tropical Tidbits)

This dry air would probably inhibit both the development or maintenance of any tropical disturbances over the next 7 to 10 days near the Southeast. It’s rather robust for early September.

Wave off Africa

The other area to watch is out in the Atlantic emerging off Africa.

An area in the eastern Atlantic has at least a 40 percent chance of development over the next week as it comes west. (NOAA NHC)

This area is fairly complex. Basically, you’ve got a large tropical wave with a couple areas of concentrated thunderstorm activity. The wave itself is southeast of the Cabo Verde Islands with heavy thunderstorms just south of the islands. Another cluster of heavy storms over Africa was going to exit near the same latitude as the Cabo Verde Islands. Over the next 2 to 3 days we’ll see this wave try to consolidate a bit as it tracks south of and just west of the Cabo Verde Islands. I don’t think we’ll see any development in that time.

A complex picture of a large, disorganized tropical wave extending into the Atlantic. (Weathernerds.org)

Once it begins to establish itself west of the Cabo Verde Islands, we’ll begin to watch for possible development later this week or weekend. Once we get there, model agreement is pretty good that something should begin to develop. You can see below that the Euro ensemble a plethora of Google AI modeling shows good agreement on a system somewhere in the middle of the Atlantic. Where the models disagree and what matters most right now for future track developments is where this will be. A slower, slightly farther north system would be apt to turn out to sea quickly. A faster, somewhat farther south system could make it to the islands before beginning to turn.

Good model agreement on some lower-end development from this African easterly wave by the weekend in the middle of the MDR in the Atlantic. (Google Weather Lab)

One thing I do see some pretty decent agreement in with the models is that very few are intensifying this system in any haste. In other words, they seem to be expecting that the basin will be hostile to tropical developments. I think this wave has an above average chance of developing but perhaps a below average chance of becoming a hurricane. A lot of modeling just disintegrates the system once near the islands as it turns northward. Bottom line: We’ll watch it like we do everything in September but right now concerns on this one are pretty minimal.

Other odds and ends

I wanted to point out a couple interesting things I’ve read since late last week.

First, Michael Lowry has a nice retrospective on Katrina.

So does Alan Gerard at Balanced Weather.

Alan also has an important post on some global issues ongoing. Ocean Heat Content is insanely high globally right now. It seems to be dominating the northern Pacific Ocean at the moment, including in Japan where multiple locations have already smashed their all-time September high temperature record today. Alan’s post also touches on the very (scientifically) intriguing and (personally) troubling potential collapse of the Atlantic meridional overturning circulation (AMOC) which is higher than we previously thought. Keep in mind that when reading this that this isn’t necessarily likely to happen today or next year or over the next 10 years, but the odds are being pushed uncomfortably high. When you assess risk, you’re assessing the chance that something happens. There’s a pretty significant difference in risk posture for when something has a “non-zero” chance of occurring versus something having odds pushing up to 25 percent. A story to continue to watch.

Opinion: Twenty years on from Katrina, have we learned enough?

Today is the 20th anniversary of Hurricane Katrina’s landfall in Louisiana. Many reflections are being written, including our own Eric Berger’s over at Space City Weather.

I don’t think we need to rehash the storm specifics, but if you’re a younger weather enthusiast reading this or you do not know the story as well as you wish, I can offer up a few reading recommendations.

I think everyone should read “Five Days at Memorial,” by Sheri Fink because it showcases the best and worst of humanity in a terrible situation, and the author does such a good job of placing the reader in the moment. That was truly a gripping book, non-fiction that reads at times like a thriller. Douglas Brinkley’s “The Great Deluge” is more like a tick tock account of how things unfolded and sets up the facts in a digestible manner. I also recommend “After the Flood,” by Gary Rivlin who did a ton of on the ground reporting in the wake of Katrina. Lastly, “Katrina: A History 1915-2015,” by Andy Horowitz ties together the very important issues of race, class, and reality that you absolutely cannot ignore when talking about Katrina.

I think there’s something to be said about forethought, planning, decision-making (deliberate and otherwise) and disaster, and reflecting on the 20th anniversary of Katrina is as good a time as any to tie that to the present day. We’ll do this again in a couple weeks on the 125th anniversary of the 1900 Galveston Storm.

Andrew Rumbach of the Urban Institute (who also writes a good publication called Place+Resilience on Substack) put together (with his colleagues) an interesting graphic that shows the last 20 years of disasters on the Gulf Coast. While Katrina was uniquely devastating, it was not a unique problem. According to their research, “disasters in the Gulf Coast since 2005 have caused $365 billion in property damage, accounting for 62 percent of all disaster losses in the US.” Just 10% of the country accounts for 62% of disaster losses. The entire report is worth your time, but while there are glimmers of positives in here the overall reality is quite sobering. I write this from Houston, Texas where disasters are on our minds frequently.

One point the article makes is that for every dollar spent by the government on hazard mitigation, the savings from avoided damages is about six dollars. So, with FEMA’s $13.5 billion in hazard mitigation funding to Gulf Coast counties, the damage avoided should be north of $80 billion, a not inconsequential number. Of course, when the total damage is over $350 billion, it makes the 80 seem less meaningful. But the message is pretty clear, and it has been for ages: Hazard mitigation is a wise investment. It’s not politically sexy to come out and say you’re going to run on a platform that will spend X billion dollars to mitigate problems that have not yet occurred. But it would be smart. A six-to-one return on investment is pretty good. Everyone wants to solve problems, but no one wants to pay to do it. And it’s a problem we have seen firsthand today.

While there have been discussions about the historic Hill Country flooding in Texas last month, and there have been some pretty standard linkages made to climate change, the reality is that this was not an unprecedented event. There is a reason the area is known as “Flash Flood Alley.” So with that in mind, it would seem obvious that foresight would go a long way here. I mean, the same kind of event happened in a similar area less than 40 years ago in 1987. This paragraph from the excellent and sobering Texas Tribune article says it all and should jump off the page smashing cymbals together when you read it.

After the 1987 flood, river gauges were installed to provide real-time information to forecasters and emergency managers. But as the years passed, political will and funding for flood warning infrastructure diminished. An effort to get flood sirens never came to fruition; local governments were repeatedly passed over for grants by the state; and the county eliminated its own flood protection tax.

When you read, it’s striking how short-sighted some of the elected officials in Kerr County seem to have been over the years.

“The thought of our beautiful Kerr County having these damn sirens going off in the middle of night, I’m going to have to start drinking again to put up with y’all,” then-County Commissioner Buster Baldwin said at a 2016 meeting.

Even after this event, there are residents in this area that are still so vehemently anti-tax that they don’t want to see any tax increase to fund warning sirens or alert systems that they feel the camps should provide. There’s clearly a disconnect here between some residents’ priorities and the reality of where they live. Even in the wake of such tragedy. I’m not here to rag on people, but it’s completely obvious that there are ways to mitigate the problem that make fiscal sense. All too often the solution is to either put a band-aid on the problem or lick your wounds and move on. This isn’t 1850. Disasters today are less failures of imagination or “acts of God” than they are societal shortcomings. More can and should be done.

The Washington Post did an investigation into an RV Park on the Guadalupe River where 37 people died last month. When lobbying to upgrade the park, the company that owned the property assured officials that they’d have an hour or two heads up on flooding and could safely evacuate the park. The developer even referred to himself as a “poor man’s weatherman,” which feels laughably condescending when considering a decision like this. The local government allowed the company to upgrade the RV Park ***in the floodway*** of the Guadalupe River. This was in 2021, four years after Hurricane Harvey exposed how much property in Houston had been built in floodways or reservoir flood pools. Again, not an unknown problem. Yet, according to the investigation, the RV Park ownership said “in a statement that the severity of the flooding on July 4 could not have been anticipated and that failures in public warning systems meant they had little advance notice.” That seems misleading at best.

The reality is that many places we choose to live in are disaster-prone because they’re often beautiful. Oceans, rivers, forested mountains. All of these places have a draw, but they also come with risk, and in some cases a lot of risk. In many ways, as Robert Paterson from the University of Texas says, “disasters are a human choice.” After these events, the blame game gets played, and in many cases now, people will blame made-up nefarious forces instead of focusing their blame on the people that often deserve the scrutiny. It’s pretty obvious that here in Texas at least, where regulation is frequently viewed as a four-letter word, we often let local governments make decisions they are not equipped to make. There needs to be some structure in place so partially avoidable disasters, like the Hill Country flood can be mitigated. I think it’s important to recognize the uncomfortable fact that a catastrophic flood occurring in the middle of the night will almost always have a bad outcome. It will always be difficult, if not impossible to get to a mythical “zero” figure in terms of damage or loss of life. Nor should we necessarily strive for that. But in reality, some thoughtful mitigation and/or regulation is better than saying something was an unavoidable disaster.

This problem is not confined to Hill Country in Texas. It’s not a problem exclusively to a red state or a blue state. This is a national challenge. We could talk about how San Antonio plans to address flooding after a deadly flash flood event earlier this summer. We could talk about how West Virginia is just now coming around to studying flooding and mitigation on Kanawha River, nearly 10 years after catastrophic flooding there. 17 years after Hurricane Ike, we’re discussing modern Galveston flood protection, the Ike Dike, and it’s still a plan on paper. The Galveston Seawall’s core structure was built in less than 10 years and began only 2 years after the great 1900 storm. And on and on and on. In the 20 years since Katrina, we’ve learned a lot but I’m not quite sure we’ve learned enough.