It only takes one: Watching the Gulf for increasing chances of legitimate tropical development

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In brief: Tropical development chances are trending up over the southwest Gulf this week. While we don’t have a fully coherent picture of what will occur, we can begin to speculate a bit on how dry air, wind shear, and the track will play out. Folks on the central and eastern Gulf Coast from just west of New Orleans through the Big Bend region of Florida will want to monitor the progress of Invest 92L.

Our disturbance to watch has been classified today as Invest 92L, and it’s an area of thunderstorms in the Bay of Campeche.

Satellite image as of 5 PM ET Monday in the Gulf. (WeatherFront)

Nothing yet. Just some unsettled weather. Over the next couple days, this is expected to gradually become better organized and a bit stronger. As of this afternoon, the NHC has pushed up the potential for development to 80 percent.

(NOAA/NHC)

So what’s going to go on here. Like I said, we expect this whole area to become a bit better organized through the week in the Bay of Campeche, and by Wednesday afternoon or so, we should have a fairly coherent area of low pressure there.

European model forecast for mid-level “spin” in the atmosphere on Wednesday evening. (WeatherFront)

It’s at this point that the models begin to diverge wildly. The GFS goes ballistic. The Google AI model begins to gradually develop it, as does Google’s 1,000-member ensemble. The AIFS model seems to follow Google’s solution, albeit weaker (though the AIFS is known for poor intensity forecasting). The European operational model peaks it as a tropical storm and weakens it on approach to the Gulf Coast, and the Euro ensemble is a mixed bag of all of the above, though with a lean toward an AIFS type outcome. So the number of solutions on the proverbial board are plentiful.

Google’s WeatherNext model showing a likely tropical storm and potential hurricane in the Gulf tracking toward the central or eastern Gulf Coast by the weekend. (Google)

I feel like the operational version of Google right now feels like a healthy compromise. Still a chance nothing comes of this, but also a 30 percent chance of a hurricane, or perhaps a 5 percent chance of a major hurricane. We’ve seen model guidance come into better agreement today, and we will want to study trends tonight for any sort of signals we can pull.

In the meantime, it seems like a significant rainstorm will precede a potential tropical storm or hurricane impact this weekend on the Gulf Coast, somewhere east of central Louisiana.

NBM model rainfall forecast through Monday morning. (WeatherFront)

I don’t want to overlook the heavy rain impact of this system because that’s going to happen whether this is a tropical storm, hurricane, or nothing at all. So, from that point of view, we’re looking at a potential for some areas of flash flooding on parts of the Gulf Coast this week.

But whether or not this organizes still matters from a wind, surge, and honing of the heavy rain forecast. It appears the system will fester in the Bay of Campeche for a couple days before beginning to turn eastward or northward by later Wednesday or Thursday. There will be a lot of things influencing and dictating the outcome here. For one, wind shear, which is expected to be plentiful in the northwest Gulf but less so in the central Gulf.

Wind shear forecast the Gulf later this week showing strong shear in the northwest Gulf. (Tropical Tidbits)

Keep in mind that wind shear has not always acted as destructively on tropical system intensity as expected, especially along the Gulf Coast and in recent years. While shear is generally going to act against development and strengthening, there have been cases where northward moving storms toward the Gulf Coast have had their outflow aided by wind shear leading to maintained intensity or even strengthening. We can also get weird behaviors when storms are transitioning more toward extratropical cyclones than classic hurricanes. In other words, while wind shear is going to be a topic with this system, if it can organize in the next few days, I would not be fully convinced that is necessarily a negative. That said, this does look rather strong, and it may be a bit tough to fully overcome.

In addition to the wind shear as a result of the pattern over the Gulf and Southeast, there’s also the situation regarding the next Pacific storm, which will likely be named Simon. If that can outdevelop Invest 92L, it could impart more destructive shear on 92L, leading to weaker development. This seems be a low likelihood (but not an impossibility) right now.

Last, we always need to watch to see if dry air is going to be an issue. Much of Texas and the Gulf Coast has or will see rain, but some notably drier air pushing offshore of Texas is likely to get drawn into the storm in the Gulf. This will probably yield at least a somewhat lopsided system, with much greater impacts east of the center than west.

Relative humidity is likely to play a role here, probably leading to a more lopsided storm and a much less intense western half. (Tropical Tidbits)

So, we have a long way to go here. At this point it looks like whatever it is will sweep north over the weekend. That leaves us a couple days to watch developments here before folks would need to prepare in earnest anywhere, if at all.

Bottom line:

  • Gulf development risk is increasing.
  • Potential ranges anywhere from a sloppy, disorganized system to a major hurricane.
  • A “worst case” type outcome is unlikely here because of the hurdles related to dry air and wind shear.
  • Likely track aims to between southeast Louisiana and the Florida Panhandle.
  • Regardless of development, heavy rainfall is likely on the Gulf Coast this week and weekend.

Stay tuned here and to your other favorite sources of weather information for updates in the coming days.

Are we heading into the grand finale of the otherwise tepid 2026 Atlantic hurricane season?

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Happy Sunday! The National Hurricane Center introduced a lemon on the map for potential tropical development over the next week earlier. It is now an orange, indicating a 40 percent chance of tropical development.

(NOAA/NHC)

This one happens to be in the southwest Gulf and Bay of Campeche, a typical launching point for tropical systems this time of year, and occasionally a place where some bigger storms can still emerge. It’s not much today, but over the next 2 or 3 days, we are likely to see a more coherent disturbance try to organize in the area of the Bay.

(WeatherFront)

Models have been on again/off again in terms of how they see this playing out. Google Deep Mind’s 1,000 member ensemble had actually had pretty strong odds earlier this past week before fading them the last 2 or 3 days. However, just in the last 24 hours, we’ve seen a shift back to a higher likelihood of development, with about half of the members doing something here.

(tcatlas-org)

So there are three things here: First, does this even develop at all? Second, how strong could it get? And third, where does it go?

The first question is the only one that has a reasonable answer right now, and that is that there is a reasonable chance, probably better than 50 percent that this does develop into at least a tropical depression. The tail end of a cold front that has delivered a bunch of rain to the Central U.S., especially Texas over the last few days is going to establish in the Gulf as the week goes on. As thunderstorms develop and fester down there, this is where we expect some organization to occur.

Upper air pattern later this week over the Gulf. (Pivotal Weather)

This setup seems to suggest a bit of a mess. A stalled front, a loosely developed tropical system, exceptionally warm water. Gulf of Mexico sea surface temperatures are at record levels for this time of year.

Water temps are the warmest they’ve been in the satellite era in the Gulf for early October. (University of Arizona)

But warm temperatures can only carry a tropical system so far. For further development, you need moist air, unstable air, and generally low shear. It would appear that the moisture and shear will be cooperative for tropical development. Will the instability? Good question. So sitting here about a week out from whatever it may be that threatens, we can say a couple things.

First, tropical development is plausible, but we cannot really speculate on how far it will go. The potential ranges from sloppy tropical depression or storm (the story of 2026) to something fiercer. The 90th percentile intensity outcome on the 50% of Google ensemble members that develop this system is a major hurricane. Given the record warm temperatures there, I would not rule anything out. A track generally north or northeast seems reasonable as well, putting Louisiana through Florida on some notice (not likely Texas). But I think what we are most confident in at this point is a heavy rain event for the Gulf Coast and Florida.

Rainfall forecast from the European AI ensemble over the next 8 days. (WeatherFront)

Rain totals could approach double digits near the Florida Panhandle. Substantial rainfall is expected on the Gulf Coast, as well as in North Florida, mainly above I-4. Flood watches are already posted near Tallahassee and in southwest Georgia

So what’s the play here? Stay tuned, as it will be an interesting week. This hurricane season has been absolutely dead quiet, but it’s those types of seasons that can occasionally produce unpleasant one-off surprises. We don’t expect that here, but it is something we’ll watch.

Flooding event escalating a bit in the Southwest with eyes on interior Texas tomorrow night through Friday

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In brief: Heavy rain is causing widespread instances of flash flooding in the Southwest. This is likely to expand into Colorado, the southern Plains, and west or central Texas tomorrow and Thursday into Friday. The Atlantic tropics remain uneventful. We may see that change in a week or so, but it’s too soon to say what that could mean.

Good evening to everyone except the Atlanta Braves and Chicago White Sox. (Your author is a Phillies and Astros fan)

Let’s see where we are with the ongoing rainstorm in the Southwest and Texas, and we can talk tropics as well.

Polo Remnant Rain

A lot of rain has fallen over the last day and a half or so in the Southwest and parts of Texas. We’ve seen as much as nearly 5 inches of rain southwest of Tucson.

Radar estimates a widespread 1 to 3 inches across Arizona and New Mexico, with numerous flood advisories and flash flood warnings as of early Tuesday evening. (WeatherFront)

We have our first “emergency” of the event, as a small portion of Doña Ana County in New Mexico near Rincon is at risk of severe flooding due to a levee breach.

Rincon, NM is under a flash flood emergency, as a levee has breached near the water treatment plant. (WeatherFront)

Rincon has seen nearly 6 inches of rain this month, almost half of which has fallen in the last 48 hours.

The entire region remains under a moderate risk (level 3 of 4) for excessive rain tonight. That shifts north and east some tomorrow, but still, portions of eastern New Mexico could see some heavier rainfall, as model forecasts are on the order of 2 to 6 inches or more, depending on which model you look at. The tropical and convective (thunderstorm) nature of this rain is such that localized areas can easily receive 1 to 3 inches of rain in a couple hours, which is when the risk of severe flooding increases.

Rainfall from this evening through Wednesday evening as forecast by the REFS ensemble, showing a widespread 1 to 3 inches. There will likely be areas with higher amounts, particularly in the higher terrain of northern New Mexico, southern Colorado, or in central and northern Texas and Oklahoma. (WeatherFront)

The highest risk of those more squirrely amounts would be in southeast Colorado or northern New Mexico. You can see those pockets of oranges showing up on the map above in those areas.

A moderate risk of flash flooding includes Pueblo, southeast Colorado, and extreme northern New Mexico on Wednesday. (NOAA)

For Texas, the situation is a little trickier. A slow-moving line of storms is going to move from West Texas into Central Texas tomorrow night, and as it does, locally torrential rain will occur. The good news is that it’s been relatively dry here late this summer. The bad news is that anytime you add 3 to 6 inches or more of rainfall in a short time, flooding can occur. This is the challenge tomorrow night and Thursday morning in parts of Hill Country.

A moderate risk of excessive rainfall for tomorrow night is in place across most of Hill Country into the western fringe of DFW and north through central Oklahoma. (NOAA)

If we look at the probability of any location seeing 5 inches or more of rainfall, what I would deem to be a more serious flash flooding threat, you can see a bullseye showing up near or south of San Angelo. Don’t zero in too closely on the exact location of this bullseye, as it’s going to be a fluid situation. But you can see those odds creeping up to 80 percent or higher. This mean that somebody, likely between Del Rio and San Angelo and west of Kerrville is going to see 5 to 10 inches of rain tomorrow night, likely to trigger some flash flooding and, locally, some serious flash flooding. The same holds true north and west of Fort Worth.

The odds of 5 inches or more of rain tomorrow night are highest in southwestern parts of Hill Country, as well as north and west of Dallas and south of Oklahoma City. (WeatherFront)

On Thursday night and Friday, this risk will shift east into the I-35 corridor to include DFW, Waco, Austin, and San Antonio. I think the risk is a little more isolated on Friday than it looks tomorrow night, but there is at least the potential for some locally torrential rainfall. And, indeed, a moderate risk for flooding exists on Thursday night/Friday AM too.

A moderate risk of flooding covers the urban corridor of Central Texas for Thursday night and Friday. (NOAA)

Bottom line: Folks in Texas, Colorado, New Mexico, and Oklahoma should be prepared for locally significant flash flooding tomorrow through Friday.

For the Houston area, check out Space City Weather for the latest on how this weather will impact that area, as we don’t expect quite the significance of flooding risk there that we see to the west.

Atlantic tropics remain futile

The eighth named storm of the docile 2026 Atlantic hurricane season formed yesterday, with Tropical Storm Hanna forming east of Bermuda. It heads out to sea and will weaken. Tropical Storm Fay’s on again/off again relationship with tropical storm intensity blossomed again yesterday only to end today. Now, Fay is officially a post-tropical cyclone, with the final advisory issued this evening.

Tropical Storm Hanna should dissipate soon in the North Atlantic. Fay is officially dissipated now in the open Atlantic. (WeatherFront)

Fay managed to rack up only 3.8 units of ACE, despite 39 advisories, which has to be close to a record for futility. That represents 40 percent of the Atlantic’s ACE to date, which should finally breach 10 units tonight. Compare that to a normal value of 95 ACE units by October 1st.

Over the next week, things should remain quiet. It continues to appear like the southern or eastern Gulf will get a little more active in about 7 to 10 days, but we continue to have no real specific read on what disturbance it would be, where it would come from, etc. It’s basically an uncorroborated threat that we will continue to monitor for now and update on by Friday if it becomes more material. At the least, I would expect to see a potential uptick in heavy rain risk in Florida in a week or so.

Nor’easter winds down as attention focuses on Southwest & Texas drenching from remnants of Polo

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In brief: Our nor’easter is winding down over the Northeast, so we take a look at some challenges this storm posed and some stats. Next, our attention shifts to Arizona, New Mexico, and Texas where significant rain may produce serious flooding in some areas, particularly north of I-10 from Arizona through Texas and west of I-35 in Texas, back toward Hill Country and in the DFW Metroplex.

Nor’easter wrapping up

This nor’easter was interesting, both in terms of how it unfolded and how it was perceived ahead of time. Most nor’easters do have an element of disparity that’s usually measured in variable snow totals or which part of the coast sees the highest winds & waves. This one had quite a dramatic disparity both in terms of where the strongest winds occurred, the most power outages occurred, the worst tidal flooding occurred, and even where the heaviest rain fell.

Estimated rain totals for the storm through early Sunday evening. (WeatherFront)

For coastal New Jersey, this was a bad event, full stop. Some of the worst tidal flooding those areas have seen in some cases almost since Hurricane Sandy in 2012. In every community, there are places that “typically flood” during storms like this. Having grown up outside Ocean City, NJ, I recall this vividly. However, this flooded a lot of places that don’t usually flood.

I’ll speculate that this was worse than perhaps anticipated in Jersey partially because tides and coastal flooding had been occurring for a couple days prior to the nor’easter forming, as well as the full moon. That’s me thinking out loud.

For Long Island, it was a solid moderate to locally major flooding event. For New England, it was a locally moderate event but mostly minor.

The heaviest rain, as expected, did fall south of Boston and east of Providence. A strong credit to the models for zeroing in on that days in advance and sticking with it. Correctly.

What was more interesting to me were the threads of disparity in terms of qualifying how bad a storm this was going to be. We tried to emphasize the coastal flooding aspect of things here. Our Thursday post emphasized that the flooding could be substantial in the back bays of Jersey and Delaware. That seems to have been correct, and it was also being emphasized by local NWS offices ahead of time. We did say on Thursday that “While this shouldn’t be a historic tidal flooding event by any means, it’ll be notable for the region.” That may have been a little bit underdone (while not a top 3 event in most cases, this did crack the top 5 to 10 in some locations).

But in some cases, folks were describing this as a historic storm, as if everyone from Delaware through Massachusetts was going to experience equally bad effects. A mutual follower here in inland Connecticut even messaged me asking why their apartment complex was saying the storm was historic. One thing I learned living in Houston for 14 years was that nuance matters in big events. A lot. A really awful storm for someone could be an absolute nothingburger for most other people. Threading that needle is difficult to message, and I’m not sure the overall perception of the storm here accurately conveyed that nuance.

Also, the only thing particularly abnormal about this storm was the calendar. Nor’easters like this don’t usually happen in September. They have in the past, of course, and they will happen again. But it’s not usually typical this early in autumn. There’s been a lot of conjecture about this storm being tropical potentially (including from us, though we said there was a chance, but that it would probably fall short) and conjecture about climate change “supercharging” the storm. As someone who supports climate change science and invoking it at times where it’s very clearly evident, I just don’t know if this was the right event for that sort of discourse. Though I suppose sea level rise making moderate flooding verify as major flooding or something like that is a valid discussion point. Because that is happening. Whatever the case, that’s my “get off my lawn” commentary today.

Polo rainfall risk

Hurricane Polo is back to a category 3 storm this evening.

Hurricane Polo this evening southwest of Baja. (WeatherFront)

Polo will turn northeast tomorrow and move ashore in Baja and then into mainland Mexico by the time we get to Tuesday morning. From here, copious amounts of moisture will surge into the Desert Southwest and eventually the Southern Plains and Texas. The first big concern will occur tomorrow night and Tuesday in Arizona and New Mexico. Here, precipitable water levels, or the amount of available moisture in the atmosphere will skyrocket to about an inch above normal, which is very strong for this part of the country. Not everyone in these areas will see copious amounts of rain, but there will be portions of Arizona and New Mexico that will be at risk for severe flash flooding.

A moderate risk for excessive rainfall is posted for the Four Corners and much of Arizona and New Mexico north of I-10. (NOAA WPC)

The Weather Prediction Center has hoisted a moderate risk for both Monday and Tuesday in the Desert Southwest, mainly north of I-10 in anticipation of numerous reports of potentially significant flash flooding. This is a very dynamic setup, so we could see some areas pick up as much as 3 to 6 inches of rainfall, while others do a half inch to an inch.

(NWS Albuquerque)

There is potential that we see Tuesday get upgraded to a “high risk” of excessive rainfall in New Mexico. The Southwest has actually seen quite a bit of rain this September, so the combination of saturated grounds and a top-end moisture event coming through is a recipe for serious flooding risk. I don’t want to overstate things, but this may be the most serious tropical system related impact in the Continental U.S. this year. Folks in the Southwest will want to monitor this event closely and be ready to act. If you can contact anyone who may be backpacking or vacationing, they should also know this is a potentially serious event.

Keep an eye on this in the Texas Panhandle as well. Speaking of…

Texas & the Plains

Beyond the Southwest, the situation gets even more complex in the Plains. The moisture from Polo and a slow or stalling cold front will probably focus repeating rounds of rain from Hill Country into North Texas. Those areas are already under a moderate risk (level 3/4) for flash flooding on Wednesday, and that will likely extend into Thursday as well.

Excessive rainfall and a serious flash flooding risk exist in Texas and parts of Oklahoma Wednesday and perhaps Thursday. (NOAA WPC)

Rain totals are likely to end up in the 4 to 8 inch range from south of San Antonio through Dallas and perhaps up toward Durant, OK through Friday. There is a chance that some areas see as much as 10 to 12 inches though, as we know Texas flood history is littered with these types of remnant Pacific hurricane events.

Rain totals through next weekend as currently forecast by NWS. Adjustments and locally higher amounts are likely. (Pivotal Weather)

Folks in Houston that read our site will want to follow Space City Weather for the latest. Eric or myself will keep you posted, but for now the more serious flooding concerns are likely to stay north and west of the Houston region. Texas folks in Hill Country and the Metroplex should monitor the next couple days of forecasts very closely and be prepared for disruptions on Wednesday and Thursday.

Elsewhere

Fay continues in the Atlantic, while Gonzalo has mercifully dissipated. Another area northeast of Bermuda has about a 60 percent chance of developing over the next couple days before dissipating. Otherwise, it remains calm.

Atlantic satellite image showing Fay and the potential next storm to its north, no threat to land. (WeatherFront)

Other than that, Hurricane Nolo has moved away from the Hawaiian Islands now and will skirt west of them over the next couple days, bringing rough seas.