Matt Lanza

Modest Atlantic development possible, while Mario will aid in SoCal storm chances later this week

In brief: The tropical wave in the central Atlantic is becoming more likely to develop over the next few days as it moves west northwest across the Atlantic. No land concerns are expected right now. Meanwhile, Pacific Tropical Storm Mario is likely to spread thunderstorm chances across Southern California later this week. We also check in on the Dakotas which had a mini tornado outbreak on Sunday.

Atlantic tropical wave

The wave we’ve been talking about since last week in the middle of the Atlantic looks pretty decent this morning. It’s certainly better looking than the previous wave we were tracking out there.

An Atlantic tropical wave is now up to 80 percent odds of developing. (Weathernerds.org)

This wave now has 80 percent odds of development per the NHC, and I imagine this will get tagged as an Invest within the next day or so. Whereas the previous wave we tracked out here had high development odds and failed to make it, this one has much less of an “all or nothing” chance to develop. There is strong model agreement in some development by as early as Wednesday or Thursday (shown).

Strong model agreement that by mid to late week we have a tropical depression forming in the central Atlantic. (Google Weather Lab)

Notice that this system is already at a fairly moderate latitude by mid to late this week, and with it continuing west northwest, we should see this pass fairly well north of the Caribbean islands. From there, it seems as though it will either curve back north and northeast out to sea, or it will continue west northwest to the north of the islands, sort of in the fashion of Hurricane Erin earlier this season, particularly if it’s on the weaker end of the spectrum. The most likely outcome is some loosely organized storm turning out to sea. But for folks in Bermuda, it probably makes sense to keep a side eye on this one through the week, unlikely as it would be to impact the island.

Generally speaking, while this is the most interesting item we’ve had in what seems like weeks in the Atlantic, it’s thankfully not a serious land threat at this point.

What’s next in the Atlantic?

The background state of the Atlantic may revert back to hostile again after about September 20th, meaning that we’re probably going to continue to see systems struggling for the end of September. Probabilities for tropical development are not exactly strong looking outside of that one tropical disturbance in the middle of the Atlantic.

ECMWF Weekly model odds of tropical cyclones for the end of September showing generally below average development odds beyond the central Atlantic wave. (ECMWF)

In fact, if anything, they’re below average off Africa and below average off the Southeast coast. I do suspect we’ll begin to see more noise in the southwest Gulf or western Caribbean, as is typical for late September and October, but aside from that, it’s becoming apparent that this is probably going to end up being one of the more subdued hurricane seasons in recent memory. Of course, one bad outcome in early to mid-October can change the whole perception, but we currently don’t see anything else out there.

Tropical Storm Mario

(Wholesale Auto Plates)

In the Pacific, Tropical Storm Mario was declared dissipated this weekend, but it turns out the princess was just in another castle. So, Mario is back to life.

(NOAA NHC)

Mario should continue off to the northwest, eventually succumbing to King Koolpa, as sharply cooler water awaits it to the north.

Mario’s tracks from various models plus water temperatures turning sharply cooler after the next 24 hours. (CyclonicWx)

So why am I taking up virtual oxygen talking about a storm that will remain offshore and dissipate. Besides the ability to add Mario puns to the post, the moisture from Mario is going to play a role in the weather in California later this week, with showers and thunderstorms likely to infiltrate from the south, particularly in SoCal. In addition to the potential for locally heavy rainfall in Southern California, there could also be some isolated dry lightning issues with respect to fire starts in parts of the interior. The entire region is under a marginal (1/4) risk for locally heavy rainfall on Thursday.

Some locally heavy rain in addition to dry lightning concerns will permeate SoCal later this week. (NOAA WPC)

Rainfall amounts will be minimal in most places, but there will be areas that see a solid half-inch to 2 inches of rain, which could cause some flash flooding in spots.

North Dakota ‘naders

Quite a day yesterday in the Dakotas. Historically, not a tornado-prone location in September (there have been only one or two historical noted reports of tornadoes in this corridor of the Dakotas since at least 1950 in September), there were nearly 20 reports of tornadoes on Sunday from at least 4 tornadoes. Reports ranged from near Mobridge, SD through Bowman, ND, Golden Valley County, and Hettinger, ND.

(NWS Bismarck)

The National Weather Service office in Bismarck is looking for reports from yesterday across the corridor in northwest South Dakota and western North Dakota. Certainly, there were a number of chasers on these storms. But overall, this was a bit of an impressive, somewhat surprising September event this far north.

Development odds increasing with next Atlantic wave, but concerns for impacts are not increasing

In brief: The tropical Atlantic has a number of items but only one really with a chance to develop much. No threats to land at this point either. Aside from that, there’s not a whole lot to say right now through about the 25th. Heavy rain and flooding chances visit South Florida and the southern Rockies today and tomorrow.

Atlantic tropics

The satellite picture over the Atlantic looks pretty noisy, but in reality only one item is truly a development candidate.

The Atlantic is noisy but not busy. (College of DuPage)

There is a cool front draped from near Florida into the Atlantic. You always watch these sorts of boundaries for any development, but there’s nothing imminent, and anything would likely track east or northeast out to sea. The big area of storms you see over the central Atlantic is an upper-level low pressure system, so that won’t develop. There’s an active tropical wave moving into the Lesser Antilles today, bringing some showers and storms but no development odds. And then there’s a broad tropical wave in the eastern Atlantic off Africa that’s now up to 40 percent odds of development as it moves into the open Atlantic this weekend and next week.

Odds of development are slowly increasing in the eastern Atlantic. (NOAA NHC)

There is decent model support still for this to develop, and this wave will have a slightly more supportive background state in the Atlantic to work with as it moves west and west-northwest heading toward next week. This is probably a more legitimate candidate to develop than Invest 91L was a week or two ago. That said, it too will be fighting both dry air and wind shear in its neighborhood as it comes across. For now, I would not expect quick, strong development, but as has been the case with almost every system this year, a slow, uneven development pace. Not much has changed in terms of track, as Eric showed yesterday. We’ll keep watching, but at this point, this system is not a real serious concern.

Beyond that, who is next? Great question. We are seeing noise from the GFS model beginning to stir up the Central American Gyre (CAG) late in the period. That’s a climatological quirk of the model, where it tends to gravitate toward development in that region, whether realistic or not. In this case, there’s not a whole lot we can truly say. If you go by the Euro ensemble (like below), you see that surface pressure is currently forecast to be higher than normal, typically not a signal for development.

The Euro ensemble currently shows generally higher than usual surface pressure in the CAG and Caribbean regions after day 10, which would indicate lower than usual tropical development chances. (Tropical Tidbits)

But that’s 12 to 13 days away, so a lot can change. The main takeaway for me as a forecaster right now? There’s not a particularly strong signal for anything else through September 25th. We’ll see if that continues.

Flood chances

Elsewhere, not a whole lot to discuss weather-wise right now. There is some flash flood risk both in South Florida and in the Southern Rockies today.

(NWS Miami)

In Florida, showers and storms will move along slowly the next couple days, bringing a chance for as much as 3 to 4 inches of rain in spots in a worst-case scenario.

In the West, the risk is on burn scars in particular, with scattered showers and storms likely today and tomorrow across southern Colorado and New Mexico, where flood watches are posted.

(NWS Albuquerque)

The heavier rain risk shifts into the Plains this weekend.

As we hit the statistical peak of hurricane season, we find ourselves in a weird position

In brief: Why is the tropical Atlantic hitting the historical peak of activity with not a wave to be found? We explain the details below, but it looks quiet for the next 7 to 10 days. Beyond that, risks will surely increase a little but how much so remains a topic of uncertainty.

Happy Tuesday evening everyone. Late today due to participation in the National Weather Association’s 50th anniversary meeting in Huntsville, Alabama, a fine city. But I wanted to catch you up on the historical peak of hurricane season.

Tropics outlook

The next 7 days look quiet. (NOAA NHC)

The outlook is the “not stonks” meme for those of you familiar with internet culture.

I mean, truly, it’s just quiet as could be. Now, it does appear we may get a wave in about 7 days in the open Atlantic that could develop. But that’s the only game in town for the next 10 days it would appear.

The next wave will emerge off Africa in a few days and may develop in 7 to 9 days in the open Atlantic. (Weathernerds.org)

An upper low in the central Atlantic, known as a “TUTT” is imparting shear on basically anything that comes off Africa, so they instantly hit a hostile environment. Additionally, there is a lot of drier air in the open Atlantic, which is not helping anything. TUTT lows drag down drier air from the subtropics into the tropics. A lack of instability, drier air, and shear are all decimating any chance at development right now. Climatology is as good a guide as anything when you look at seasonal predictability and timeframes for activity, but if the key ingredients aren’t there, they aren’t there. The cookbook recipe may say that the cake needs flour, butter, and eggs. But if you leave the flour and butter out, you aren’t baking a cake using that recipe.

Strong wind shear is hampering development, in addition to other factors. (Tropical Tidbits)

In addition to this, in the western Atlantic there is high wind shear as well. So we have a number of highly problematic factors right now as it relates to tropical development. Good for almost everyone!

Now, after 10 days the forecast in the Atlantic seems to favor a slightly more favorable shift for tropical activity. At least we should see more instability out there. That being said, I have seen a couple instances this hurricane season where tropical Atlantic conditions were expected to become more favorable “in 10 to 14 days,” and those conditions ultimately never materialize. That could be true here too. But given our streak of good luck, one figures it can only last so long. At the least, we will probably start to see GFS operational model runs showing tropical development in the Caribbean or Gulf soon. Please remember that this model has a very well-known bias to overdo that activity in most cases, particularly beginning in later September and October, as well as in May and June.

Bottom line: Enjoy the respite from peak season activity. But we still have about half the season’s activity in front of us historically. We’ll keep you posted.

125 years after the Great Galveston Hurricane, it still remains relevant if we’re willing to listen

In brief: Today, we reflect on the 1900 Galveston hurricane, which made landfall on this day 125 years ago. The lessons before and after the storm ring loudly today in an age where disaster is happening to more people more frequently.

On July 16, 1891, a byline in the Galveston Daily News attributed to Dr. Isaac Cline was published. The sub-headline read “Record of twenty years — The Texas Coast Not Liable to Serious Damage.” Essentially, Cline was using the best knowledge of how things worked at that time to try to explain why he believed the Upper Texas Coast was immune to disasters, such as the 1875 Indianola Hurricane.

July 16, 1891 Galveston Dailly News. Click to enlarge.

After seeing what happened to Indianola in 1875 and again in 1886, some residents of Galveston had felt they needed a seawall for protection of the city. Cline, among some others did not believe this was necessary. In fact, in this 1891 article, Cline wrote this:

The opinion held by some, who are unacquainted with the actual conditions of things that Galveston will at sometime be seriously damaged by some such disturbance is singly an absurd delusion and can only have its origin in the imagination and not from reasoning; as there is too large a territory to the north which is lower than the island over which the water may spread, it would be impossible for any cyclone to materially injure the city.

While it may seem patently absurd today that any learned individual would ever say something like that with such confidence and in that tone, keep in mind again the context of the day. This was not a deranged individual. This was how even brilliant people thought about things in that era. But in hindsight, it tells us a lot about hubris and an invincibility complex.

The storm

It was today 125 years ago that hell was unleashed on the Texas coast. The great Galveston hurricane remains the deadliest single weather event in our nation’s history. Despite how it may seem in hindsight, it wasn’t inevitable. And despite it happening 125 years ago, it remains as relevant today as it was in 1900. Most of us know the general theme of things. The hurricane struck Galveston, delivering the full fury of the Gulf of Mexico onto the island, washing away virtually every structure on the Gulf side of the island. The death toll ranged from 6,000 to 12,000 based on various estimates. The storm’s impact was well documented in several books. Obviously, “Isaac’s Storm” comes to mind first and foremost, telling the story through the life of the weather bureau chief in Galveston, Isaac Cline. “A Weekend in September” remains a classic for this topic as well. I am fortunate to also own an original copy of the “The Great Galveston Disaster,” which contains accounts and details of the storm’s impacts.

But the Galveston storm also had noteworthy impacts near and far from Galveston.

A selection of headlines from the Houston Post describing loss across Southeast Texas.

Across Southeast Texas, damage was everywhere. Bayshore communities were devastated with significant loss of life. Inland locations from Houston to Richmond to Brenham suffered extensive, widespread damage and lesser but not inconsequential loss of life. A similar storm today, a large category 4 hurricane would probably cause north of $100 billion in damage, with significant risk to the Houston Ship Channel, an economic engine for both Texas and America.

The 1900 storm remained a tropical storm into Oklahoma before it became post-tropical. But the 1900 storm was clearly fueled by the jet stream after that, and it reintensified as an extratropical cyclone over the Midwest and Great Lakes.

“Texas Blasts Strike Chicago” (Chicago Tribune)

As the storm moved into the Great Lakes it produced wind gusts over 80 mph in Chicago, 78 mph in Buffalo, and 74 mph in Toronto. Flooding occurred in Minnesota, two were killed in Chicago, and “severe damage” was reported in Buffalo.

As it passed north of an extremely dry New England, it helped fuel significant wildfires that broke out in southeast Massachusetts and Cape Cod.

New England “swept by gales and forest fires.” (Boston Globe)

Water scarcity had been a problem in 1900 in New England, with shortages reported in New Hampshire and Connecticut. The passing of the hurricane, with drier air on the back side and gusty winds led to a rough setup that helped produce fires.

In Canada, the damage was immense in the Maritime Provinces with strong winds and numerous shipwrecks. Over 50 were confirmed killed in Canada, making the 1900 storm the 8th deadliest storm on record there. However, unofficially, the toll was likely higher, and the 1900 storm may be as high as the third deadliest (possibly over 200 perished).

The footprint was massive, and in 2025, this type of storm may not cause as much loss of life but would still cause immense damage. We got a sampling of this with a similar storm to the 1900 storm, Hurricane Ike in 2008. Ike caused over a half-billion dollars in damage and wind gusts of hurricane-force inland across interior parts of the U.S.

Response to 1900

Recall at the beginning of this post, we noted how the 1875 Indianola hurricane planted the seed that never germinated in time. After the storm, the reaction was quick. The Seawall began construction in 1902 with the first segment completed by 1904. The length was over 3 miles. An additional extension just under a mile was completed in 1905 to protect Fort Crockett. The first three miles were approved by the Texas Legislature and funded by the issuance of bonds in Galveston County. The section protecting the fort was funded by Congress. The Seawall was further extended in 1927 and again in 1963. In addition to that, 500 city blocks were raised in elevation by 1911. This was the largest civil engineering project in American history at that time and stands as one of the most enduring.

The track of the 1900 Hurricane vs the track of the 1915 hurricane vs Hurricane Ike in 2008. (NOAA)

The Seawall paid dividends almost immediately. In 1915, a very similar storm to the 1900 one struck nearly the same exact place. We’d be the first to tell people that no two storms are identical, but in this instance, the difference was so dramatic, it needs mention. While the 1915 storm did do a fair bit of damage, the devastation that was seen in 1900 was not repeated in any way. The loss of life was around a dozen in Galveston proper, with many others lost elsewhere on Galveston Island and along the bayfront closer to Texas City. But the Seawall stood the test. It was the true definition of hazard mitigation.

When Hurricane Ike hit in 2008, the damage in Galveston proper was primarily caused by bayside flooding, as Ike took a slightly farther north track. The Coastal Barrier project, or “Ike Dike” as it’s commonly called would substantially mitigate this type of flooding, further bolster the Gulf side risks, and provide a layer of protection that does not currently exist for the Houston Ship Channel.

The 1900 storm still matters a lot today for the toll it took and the lessons it left behind

I’ll say it again: Hurricane Ike hit the Texas Coast in 2008. 17 years later, the Ike Dike is a plan on paper that’s funded sort of, but not really. After 1900, the people of Galveston recognized what had to be done and did it. It’s a different world today of course, and these projects are more complicated, more thorough in planning, done more safely, and they’re just more expensive. But here’s the thing about large mitigation projects: They save more than they cost. The Galveston Seawall is a testament to that. It was created as a reactive solution to a permanent, existential problem. What has it done? Saved hundreds of millions of dollars in damage and countless lives. Will the Ike Dike do the same thing? The better question may be: Would the Seawall have prevented the 1900 tragedy? The answer is probably yes, even if in truth, there’s no way to know for sure. But the plans for the Ike Dike seem reasonable, and we know that mitigation money pays back about $6 in avoided damage for every dollar invested.

Ingenuity and a sense of existential risk to a community brought people together after 1900 to plan and implement a radical change. As we move forward through the 21st century, we are going to need that same sense of thinking for the greater good of our communities. It’s likely that some communities will face existential threats to their survival, be it through sea level rise, storms made worse by warming oceans, or simply infrastructure that’s unfit for the current population. These risks aren’t unknown. We know what many risks to our communities are; they aren’t theoretical. Had Galveston followed down that line of thinking in the 1890s, the 1900 storm may have been a footnote in history. The lesson from 125 years ago stands today: Proactive investment in hazard mitigation for our communities allows them to survive and prosper, and that’s good for everyone.