In brief: A surge of tropical moisture is headed toward the upper Texas coast today, and we explain what that really means. After shower chances today we will have a hot and sunny weekend, with zero risk of inclement weather.

Tropical moisture, but in a good way

When it comes to weather, living near a huge body of tropical water such as the Gulf has its upsides and downsides. Among its benefits are a moderating impact on colder temperatures during the winter, and a ready source of moisture when we otherwise might plunge into drought. On the downside is that sometimes that “ready source of moisture” provides a little too much tropical moisture.

When we speak of tropical moisture it simply refers to moisture that originates over very warm tropical or subtropical bodies of water, and what differentiates it is that this warmer air is capable of holding more water vapor. This creates deep layers of more humid air and very high levels of “precipitable water,” the amount of liquid water if one were to condense all of that vapor in the atmosphere from the surface to space.

Thus, tropical moisture is capable of producing high rainfall rates. So when we have a tropical storm, it brings not only a surge of tropical moisture, but a very efficient atmospheric machine in terms of wringing that moisture from the atmosphere and generating heavy rainfall. We sometimes see rainfall rates of 3 or 4 inches per hour (or higher!) instead of the more common 0.5 to 2 inches per hours. Higher rainfall rates quickly back up streets.

Anyway, all of that to say we have a surge of tropical moisture headed toward Texas this morning. It presently is over the northwestern Gulf, but will soon move into the Houston region. This will bring some decent rain chances into our area, especially (but probably not exclusively) for areas south of Interstate 10. But since we lack a tropical storm-like environment, the showers will be more scattered and fleeting in nature, so we shouldn’t worry too much about flooding. For most of any rains today would be beneficial.

Thursday

As noted above, we have a healthy chance of showers today, which is notable because it’s probably our last significant chance of rain for several days. Most areas along and south of I-10 could pick up a few tenths of an inch of rain, but there is the potential for higher isolated totals. Coverage and amounts will be less further inland. With increased cloud cover our highs should be around 90 degrees, or perhaps a little warmer inland. We may see some gusty easterly winds. Lows tonight will be in the upper 70s.

Friday, Saturday, and Sunday

For the weekend we are very unlikely to see any rain, and skies should be sunny. On Friday we should see some slightly drier air, and this will lead to slightly lower humidity during the daytime. It won’t be much, but you may notice it. The effect should fade out on Saturday and Sunday. Highs this weekend will be in the low- to mid-90s with nighttime temperatures generally in the mid- to upper-70s.

Next week

This warm, late summer pattern should persist for most of next week, with mostly sunny skies and highs in the low- to mid-90s. We may start to see some low-end rain chances during the afternoon hours along with the sea breeze, but these are only going to be in the 10- to 20-percent range, probably. Some kind of a pattern change, or possibly a weak front, remains possible during the later stages of next week but again, there are just no guarantees at this point. We are watchful and waiting, but prepared for disappointment. That should probably be this website’s motto for September, no?

In brief: In this post we go deep on what’s happening with El Niño, and what it means for Houston and Texas, and globally as well. Basically, we are in uncharted territory here.

What is El Niño and why do we care

El Niño is the periodic warming of sea surface temperatures in the tropical Pacific Ocean. Historically water temperatures in this area have oscillated between warmer than usual (El Niño), neutral, and cooler than usual (La Niña). These changes can generally be predicted several months in advance. We care because El Niño and La Niña affect weather and climate around the world.

This year we care more because El Niño is already very, very strong, and it is likely to reach even higher levels this fall and winter. NOAA currently estimates that during the period of October to December there is a 75 percent chance of a historic event that would exceed the strength of previous El Niño events dating back to 1950. In short, this could be the strongest El Niño in the modern observational record.

But should we care?

Actually, you probably should. However it probably is not going to bring certain doom, or anything, locally. As with any weather or climate phenomenon, when you start to talk about extremes like this, there is going to be an extraordinary amount of information, misinformation, and hype. But El Niño can be a truly impactful event, and indeed we are already seeing some of its impacts.

Such as?

Take a look at the 2026 Atlantic hurricane season. This past week represents the utter peak of the season, and it has been dead quiet out there. El Niño is not the only reason for this, but it is the predominant factor. The Atlantic has never gotten this deep into the season, in nearly 150 years of records, without the development of a hurricane. And yet here we are. It’s quite astounding to have such a low amount of activity.

But that’s a good thing …

It certainly is. El Niño can have beneficial effects, and increasing wind shear across the Atlantic tropics is one of them. As for our weather for the rest of this year, and early 2027, the result is a mixed bag. Typically during an El Niño winter we see a more pronounced subtropical jet stream across Texas. This means more upper-level disturbances.

In terms of weather, generally this brings above-normal rainfall and slightly cooler than normal temperatures during the winter months in Texas. To be clear, this is not a signal for a hard freeze or a major snowstorm. There is not a significant association between these weather patterns and El Niño. However it does mean we are likely to see more cloudy days during the winter, and the likelihood of more severe thunderstorms and possibly flooding events.

All in all, the local impacts of El Niño are not too serious for Houston. But that’s not the end of the story.

El Niño has global impacts

The potential is high for disruptions around the globe, and that’s not great for economies already strained by wars in Ukraine and the Middle East.

Let’s start with the Panama Canal, which relies on water from Gatún Lake to raise and lower ships traversing the waterway. During El Niño, precipitation is typically lower across parts of Central America, including Panama. The Canal Authority has already begun reducing the number of daily slots for large ships to move through the canal due to lower precipitation. There is not a global shipping crisis yet, but ongoing drought in the region could have even more significant consequences this winter and into 2027.

Similarly, El Niño often causes droughts in Southeast Asia delaying the production of rice and other important agricultural crops in places such as Thailand, the Philippines, Vietnam, and elsewhere. According to the World Food Program, tens of millions of people could face acute hunger due to the strengthening El Niño. There will likely be similar disruptions in other parts of the world.

Lots of uncertainty

One of the biggest concerns I have about this El Niño is that we are headed into unknown territory in terms of the strength of this event, and its impacts on a more populous, interconnected world. This creates tremendous uncertainty about the severity of impacts locally and globally.

Global temperatures are going to spike

Typically global temperatures lag behind El Niño by a few months. This means that temperatures in 2027 will almost certainly be the hottest on record. During the 1997–98 El Niño, global temperatures jumped substantially in 1998, which became the warmest year then observed. This also occurred during the major El Niño in 2015-2016, and the 2023-2024 El Niño, when 2024 reached about +1.55°C above preindustrial temperatures, becoming the hottest year recorded in the modern era.

Now we have an El Niño that is going to be stronger than any of those, with a world already experiencing rising temperatures due to global warming. Global temperatures are likely to spike. In Texas, the influence of El Niño is less pronounced in the summer than winter, but I think we can safely predict a tremendously hot summer next year locally, and around much of the world.

A message from Reliant

At Reliant, we’re grateful to Eric and the team for their no-hype outlooks and helping us navigate the varying weather El Niño may bring our way. When weather is cooler than normal in the winter and hotter than normal in the summer, it can make air conditioning and heating systems (HVACs) work even harder to keep up. Maximize your home’s efficiency with tips for HVAC maintenance, thermostat settings and seasonal adjustments to help you save and stay comfortable year-round with these energy efficiency tips.

In brief: Houston tied a record high temperature on Tuesday, which tells you about all you need to know about how this week’s weather is going. We will see some slightly drier air this weekend, but unfortunately next week looks nearly as hot.

The mid-90s will continue until morale improves

The first few days of September started out with near-normal temperatures. But the second week of September has put up a number of high temperatures in the mid- to upper-90s at a time when our daily highs should be trending down toward about 90 degrees. The last several days have been especially hot—not quite August, but almost. We even tied a record high (98 degrees) on Tuesday.

The bad news is that, despite a small amount of drier air on Friday and into the weekend, we are going to see continued hot weather well into next week. I think we can safely expect mid-90s through the middle or end of next week, without much reprieve. The chances of a substantial front making it through before the end of September are now not zero, but they are decreasing day by day.

Wednesday

Today will be similar to Tuesday, with temperatures flirting with the record high for today (98 degrees) for inland areas. The point is, it will be very hot for this time of year. We are going to see mostly sunny skies. Some showers did develop over central parts of the region on Tuesday, and we will again have some spotty rain chances locally, but most of us will just see sunshine. The air remains very humid, with lows tonight perhaps only briefly dropping below 80 degrees.

Thursday

With a surge of moisture we will see some slightly better rain chances on Thursday, especially for coastal counties. These areas may have as much as a 50 percent chance of seeing showers and thunderstorms, some of which may be fairly intense. However those chances fall off rapidly the further one moves inland, especially north of I-10. With a few more clouds on Thursday, we may see highs only reach the low- to mid-90s.

Friday, Saturday, and Sunday

A slug of slightly drier air arrives on Friday, and this will allow for hot days with slightly lower humidity, nights a touch cooler (in the mid- to upper-70s in Houston, with cooler conditions north), and lots of sunshine. Expect highs generally in the mid-90s this weekend with a near zero percent chance of rain. Seriously, if you have outdoor plans you can make them with confidence (and sunscreen).

Next week

We remain in a hot and sunny pattern at least through the middle of next week. Daily rain chances may creep up into the 10 to 30 percent chance range, daily. There is the potential for a slight pattern change during the second half of next week, although I have limited confidence in the forecast at this point.

El Niño is strong, or what?

We’ve received a ton of questions about El Niño, what is means for Houston, and whether we should be truly concerned about a historically strong El Niño. Check back later this morning, at 10 am CT, for some answers in a dedicated post.

In brief: We have now reached mid-September and a summer-like pattern remains largely in place across the state. Does this mean September in Houston is actually worse than August?

Is September bad, or not?

Matt and I routinely debate whether August or September is the worst month in Houston. I say August because it is guaranteed to be sizzling hot, and there is no hope for respite. Matt argues that September is worse because it holds the false promise of fall, when it fact the region typically does not experience meaningful cooling until October. Alas this September is doing me no favors, with statewide temperatures running well above normal and fall nowhere in sight.

This week offers a meaningful example. Last week the models were teasing us with a cool front around the Friday or Saturday period, but now as we get closer to that time frame we can see that, at best, we are going to receive a slight push of drier air. That’s not what we all wanted, but so it goes with phantom fronts in September. Anyway, I still think September is better. I like the slightly cooler daytime highs, and with shorter days the evenings cool off a little faster. But September is definitely not fall in Houston.

Tuesday and Wednesday

With high pressure more or less holding on, we are going to have a pair of mostly sunny days with high temperatures in the mid-90s. We should see a puncher’s chance of showers on both days, with perhaps a 20 percent chance south of I-10, and slightly less inland. Winds will be light, generally from the southwest. Overnight lows may briefly drop into the upper 70s.

Thursday

We are going to see a surge of atmospheric moisture on Thursday, and this will bring a few more clouds in the sky and improved potential for some rain. Shower chances are probably 50 percent for areas south of I-10, and 30 percent for areas further inland. With more clouds, high temperatures for most of the region should max out in the lower 90s.

Friday, Saturday, and Sunday

We are likely to see some slightly drier air this weekend, but set your expectations to “low.” We should see mostly sunny skies this weekend with highs in the low- to mid-90s thanks to slightly lower humidity. Nights may be a few degrees cooler, with lows in the mid- to upper-70s. Rain chances will be near zero. Mornings and evenings will be tolerable outside, if not overly pleasant.

Next week

Similar weather continues next week. After a dry weekend, some slight rain chances may return by the middle of next week. As for a front, maybe there’s something to watch for eight to 10 days from now? But we are still in the “hope” stage rather than the “expectant” stage.