In brief: In today’s post we talk about the region’s flirtations with fall, and we are going to have a couple of very fine days with cooler nights. But after this a warmer and somewhat more humid pattern returns, although we are beyond the worst of summer. Dwight also checks in with an update on our app!
Fall’s first front
A decent front has pushed offshore, and we are seeing rather dry air move into the region. As as result humidity will feel decently low today and Tuesday. The big question for me is, will we hit 65 degrees tonight? It’s going to be close. That is our arbitrary definition of the first fall-like weather in the city. Since the city’s official station moved to Bush Intercontinental Airport in 1969, the average date of the first 65-degree (or cooler) night has been September 12, so we’re close to that time of year. Regardless, it will feel notably cooler tonight than we have experienced since May 12.
As you can see a front has moved well offshore. (National Weather Service)
Final app update🤞🏻for 2025
(The following update comes from Dwight). As summer fades, so does our annual development push for the Space City Weather app. Over the past couple of months, developer Hussain Abbasi has been cranking away on updates for the Apple and Android versions, smashing bugs and tuning the apps for performance. We think both are in a good place right now, and pending any undiscovered issues, we’re happy. We hope you are, too!
And you appear to be, because over the past few weeks, the number of bug reports we’ve received have dwindled to near-nil. Thanks to everyone who used the Send Feedback button in the app to make those reports. They help!
And as part of our new Discourse platform, which handles blog comments in a forum setup, we have added a new category: App Feedback. Got comments, questions, concerns or feature requests? App Feedback is the place to leave them. In addition, we’ve got an initial post which serves as a mini FAQ about the SCW app, with a few Good Things to Know™ as well as instructions for filing a bug report. Please give it a read before posting in this new forum category, because there’s a good chance your question is already answered there.
As always, thanks for downloading and using the app!
Low temperature froecast for Tuesday morning. (Weather Bell)
Monday
Today will be sunny and warm, with a high temperature in the upper 80s to 90 degrees for the metro area, with a northeast wind of about 10 mph. I highly recommend planning to spend this evening outdoors because it is going to be lovely, with mild temperatures and drier air. Seriously, this is porch weather. I don’t have a great handle on how low temperatures will go tonight, but I think Houston will fall into the upper 60s, with inland areas dropping into the lower 60s to upper 50s.
Tuesday
This will be another day with reasonably dry air. Expect sunny skies and highs around 90 degrees. As winds shift to come from the east humdity will start to come up a little. Still, I expect Houston to see lows around 70 degrees with inland areas dropping into the 60s on Tuesday night.
Yes, this coming week will be hot, but we’re beyond the oppressive heat of peak summer it seems. (Weather Bell)
Wednesday, Thursday, and Friday
We return to a more summer-like pattern for the rest of the week as high pressure starts to build. However since we’re now approaching mid-September, this means highs generally in the low- to mid-90s, with nights in the mid-70s. Dewpoints will be high, but not opppressively so. So hot, yes. But super hot, no (see, for example, the wet bulb globe temperatures in the graphic above). Expect sunny skies and no rain.
Saturday and Sunday
The weekend looks the same: Sunny skies, highs in the low- to mid-90s, with a fair but not exessive amount of humidity. Rain chances appear to be close to zero through the weekend.
Next week
This pattern of highs in the low- to mid-90s should persist into next week as late summer holds on. Some rain chances may finally return to the forecast about 10 days from now.
The Atlantic tropics
Things are surprisingly quiet right now for September, with zero threats in the Atlantic. We only have a few weeks left of “prime time” for storms in Texas. Tomorrow I’ll take a look at what may happen during that time.
In brief: Houston will see more humid weather this weekend with rain chances re-entering the forecast slightly today and tomorrow and more so on Sunday as a weak front approaches. Though locally heavy rain is possible, we don’t expect widespread heavy rainfall. Temperatures will be warm by day and cooler again by night early next week before a late summer hurrah arrives again after Tuesday or Wednesday.
Programming note
If you live or work in the City of Houston, you are going to receive a test emergency alert this morning at 11 AM. It will look like an Amber Alert, except it will read “TEST Wireless Emergency Alert from the City of Houston Office of Emergency Management: No Action Required. TEST ALERT. For more information visit HoustonOEM.org.” The test is meant to only go out to anyone in Houston at that time, though because it’s targeted to specific cell towers, you may be in an adjacent location and still receive it as well.
Tests like this are necessary periodically to ensure the system works properly. WEA cell alerts have been a source of, shall we say, consternation in recent years for a number of reasons. They’re well-intentioned but in some cases not always relevant. Ignoring the broader conversation around those sorts of public safety alerts, we will note that weather alerts are quite relevant. Only higher end flash flood warnings will get pushed to your phone. I think this topic takes on some renewed relevance in the wake of the July 4th Hill Country tragedy, something we can discuss more another day. If you’ve turned them off in the past and want to turn them back on:
iPhone: Go to Settings > Notifications, scroll to the bottom under Government Alerts, and you can turn on Emergency Alerts there.
Android: Go to Settings > Safety & Emergency > Wireless Emergency Alerts, and you can enable Allow Alerts.
Anyway, we just wanted to make sure you knew that was coming today.
Today
I’m not sure if anyone else felt this way, but yesterday seemed really nice. We had very few clouds and generally tolerable humidity, although it was fairly hot by late afternoon. It sort of “looked” like a change of seasons was slowly beginning.
24-hour dewpoint changes show generally higher humidity across most of the Gulf Coast versus Thursday morning. (NOAA WPC)
Of course, humidity is notably higher already this morning, so that autumn thinking may be short-lived. Expect a similar day overall: Sun, a few clouds, and highs in the mid-90s, possibly upper-90s — but with more humidity than yesterday. An isolated shower or storm could pop up this afternoon as the sea breeze moves inland, but most folks should stay dry.
Weekend
There has been some discussion around Lorena in the Pacific and how it may fling some higher moisture in our direction later this weekend. Well, Lorena’s forecast has changed significantly in the last couple days. It’s now post-tropical, and it’s expected to make a U-turn back out into the Pacific. While overall atmospheric moisture increases this weekend, the threat for any significant heavy rainfall has come off some.
Total rainfall this weekend should average a quarter to half-inch, with some seeing less than that and others seeing locally higher amounts. (Pivotal Weather)
Expect at least isolated thunderstorms Saturday and more scattered to perhaps even numerous storms on Sunday as another (!) front approaches. Locally heavy rainfall could occur, but widespread, significant rain is unlikely. Still, if you’ve got outdoor plans this weekend, just consider a backup in case a downpour passes by. Highs will be in the upper-80s to low-90s due to clouds, with high humidity.
Next week
With drier air filtering in behind the front next week, we will probably see low temperatures drop back into the low-70s or even upper-60s in spots. High temps will likely remain rather hot in the low to mid-90s. Our autumn fling will probably end after early next week, as high pressure tries to build and expand over the Southern Plains. Better now than in July or August, I suppose.
Above normal temperatures will re-establish over the Plains by later next week. (NOAA CPC)
Whatever the case, look for a late summer hurrah beginning after midweek next week.
In brief: The region will heat up today and Friday, with moderately drier air in place. A combination of factors, including a slow-moving front, will bring elevated rain chances this weekend, particularly on Sunday. Slightly cooler weather will follow.
It is starting to look a little bit like fall across Texas this morning. (Weather Bell)
Thursday
A close look at the radar reveals a few showers right along the coast this morning—that’s the stalled front that has brought modestly cooler weather into the Houston region this morning. Lows at Conroe have dropped all the way into the mid-60s, but most of the metro area has settled into the low 70s. Because this dry air warms efficiently, and skies will be sunny, we will see highs today in the mid- to upper-90s for much of the region away from the coast. With dewpoints in the 60s this afternoon it will be a slightly drier heat, but it’s still going to be pretty hot. Winds will be light, from the west at about 5 mph. Lows tonight will be a couple of degrees warmer than this morning.
High temperature forecast for Thursday. (Weather Bell)
Friday
This will be another sunny and warm day, with highs in the mid-90s for much of the area. However, winds will turn more southerly, with gusts up to 15 or 20 mph, and this will herald the return of the onshore flow. This is one factor that will lead to higher rain chances over the weekend, but only one. Friday night will see lows drop into the upper 70s.
Saturday
The first half of the weekend will see a few more clouds in the sky, but there should be enough sunshine to help push temperatures for most into the vicinity of 90 degrees, or just above. Rain chances are about 40 percent, but for the most part I think any showers that develop will be light to moderate, and not super impactful. With ample humidity in place, look for a warm Saturday night.
Sunday
Rain chances will peak on Sunday, likely in the 60 to 80 percent range. Why? Because the combination of a front dropping down from the north, along with an influx of moisture from the remnants of Hurricane Lorena in the Pacific, should bring a healthy chance of showers across the area. We certainly cannot rule out the threat of heavy rainfall, but at this time I expect most of the region to pick up between 0.25 and 1 inch of rain this weekend, rather than seeing any significant flooding. But we’ll keep an eye on it. Highs, for the most part, should top out in the upper 80s.
NOAA rain accumulation forecast for now through Sunday. (Weather Bell)
Next week
At this point it looks like the front will drag into Houston on Sunday-ish, and stall out near the coast. Depending on where the front stops, we could see some lingering showers next week for coastal areas, or they should remain offshosre. Regardless, we should see a couple of days in the upper 80s to 90 degrees, with nights in the lower 70s. Some inland areas may drop into the upper 60s again, so pretty nice overall. Most of next week should be sunny.
Tropical outlook for Thursday morning. (National Hurricane Center)
Tropics
A disturbance progressing across the Atlantic is increasingly likely to become a tropical storm, and then possibly a hurricane over the course of the next week. There remains a ton of uncertainty about where this will ultimately go, and since it is early September we need to keep an eye on its development. However, overall the odds of this system affecting Texas look to be quite low at this time.
This installment of the Space City Q&A is particularly tasty: Y’all came up with some very good questions! Keep them coming: Hit the Contact link at the top of the blog, or leave a query in the Discourse comments below this post.
Q. I have a question as to how weather radars generate their one-hour plus future radar loop. Some recent rain showers have been from storms that kind of pop up on the radar, meander around for a bit and then dissipate. They usually don’t have an easily defined direction to them like they might have if they were spawned from a frontal boundary moving in. However, on most radar loops that I watched, as the radar passes from the older, real radar data to the projected data, the storms go from wandering with no direction to a well defined direction. In reality, as time moves forward the storms end up meandering and don’t go in the predicted direction. Any thoughts as to why this occurs?
A. I am not an expert in predictive radar apps, but I have done some research in this area in the past. So I’m going to dive in a little bit here because I think it’s a good question.
First of all, as you’ve suggested, these predictive apps work best when there are clearly defined storm motions, such as along a frontal boundary. This is because the “nowcast” for 0 to 60 minutes is based on current radar readings and inferred motion vectors based on storm intensity, speed, and direction. More sophisticated methods might also incorporate flow equations, such as the Lucas–Kanade method. (Dear reader, it has been 30 years since I took an advanced mathematics class, and I’m not going to try and explain how that works. Because I really don’t know.) These forecasts are quite accurate for storms with clearly defined motions, but less so for other storms. I would trust them for about 30 to 60 minutes out, at most.
Predictive radar features found in popular weather apps, such as this one from Apple, are most accurate at 30-60 minutes.
Then there are medium-term forecasts that run from 1 hour out to several hours. These generally rely on a single high-resolution model, such as the High-Resolution Rapid Refresh (HRRR), or a blend of models with some AI-enhancement thrown in. Again, for something like a line of storms ahead of a frontal passage, these can be pretty accurate. But if storms are just popping up around the city during the afternoon, they’re probably not going to reliably tell you if it is going to rain at your house three hours from now. I mean, sure, they’ll get lucky some time. But they’re also going to miss. I wouldn’t trust any predictive radar app more than a couple of hours out.
–Eric
Q. It’s not new, but it feels more noticeable lately with the new weather reporter at the Houston Chronicle. I usually read him, check your forecast, and glance at the iPhone app. A recent day offered a good example: he predicted highs in the upper 90s, possibly hitting 100. My iPhone said 89. You (correctly) called for mid-to-upper 90s. How can one source call for 100 while another is calling for 89? I guess it feels like the spread is getting wider, not narrower. I’d expect the opposite with improved technology. I assume it comes down to different models, how showers affect afternoon highs, and maybe even some editorial choices (the Chronicle does seem to lean into more dramatic weather headlines recently).
A. I can’t speak for the Chronicle’s forecasts, but I know Justin Ballard tries to do a good job. And if there are sensationalistic headlines, they’re generally coming from online editors pressured to drive up traffic numbers rather than the forecaster. I dealt with this when I worked for the newspaper, which is one reason why I very much prefer working for myself.
Anyway, I suspect it may be a combination of things. When I say the highs in Houston are likely to be the mid- to upper-90s, I’m referring to the central portion of the area, i.e. Harris County. Daytime temperatures in the summer will invariably be cooler in Galveston, near the water, and often warmer further inland, such as in Conroe or Sealy. Perhaps Justin was referring to the forecast at Bush Intercontinental Airport, and I was more considering Hobby. That would explain the variance in our forecast.
As to why the iPhone said 89 degrees, perhaps it was forecasting an afternoon shower to keep things cooler? I don’t really know. But in general, a lot of the variety in temperature forecasts for Houston are due to its large area (more than 90 miles from Galveston to Conroe), varied nature of the terrain, urban heat island effect for the city’s core, and surface temperatures of the Gulf of Mexico. It’s … a lot to balance.
–Eric
Q: As far as climate change goes, rising global temperatures get a lot of attention, I was wondering if global humidity levels are trending upward, too? This year may be more an extreme example, but I was wondering: As the temperature rises, and more water evaporates from the oceans and other bodies of water, giving precipitation events “more to work with.” i.e. Has there been a noticeable shift upward in global average humidity levels?
A. When you think about humidity here in Houston – or “houmidity,” as we sometimes call it – you (should) think about dewpoint. Dewpoint is a measure of moisture in the air; it’s the temperature that the air would need to cool to for it to be saturated. When dewpoints are high, it feels very humid, hence why Houston’s summers are so generally awful; we have dewpoints often in the mid-70s to even upper-70s at times. Periodically, the immediate Gulf Coast can see dewpoints of 80°, and there have been instances of some places in the Middle East (Iran in particular) seeing dewpoints over 90°!
Why does it feel so humid? Warmer air holds more moisture. You could have a relative humidity of 100% with a temperature of 50° and a dewpoint of 50°. That feels damp or clammy, but it isn’t oppressive. But if you have a dewpoint of 75° and an air temperature of 75°, that feels disgusting. The relative humidity is 100% in that case too. But because the air temperature is warmer, it’s holding more moisture.
Houmidity is front and center in the Space City Weather app. (And remember, that spelling is a not a bug, it’s a feature!)
Thus, as climate change continues, we will see global humidity levels increasing too. A warmer planet has more capacity to hold moisture, so generally the humidity and dewpoints will be higher. You can read more from the UK Met Office here. Thinking about this locally, 2025 sure seemed like a fairly mild summer by almost anyone’s standards in Houston. But it was the 6th warmest on record because our nighttime lows were second highest on record. Put simply, the daytimes weren’t so bad, but the nighttimes were persistently very warm, even by Houston standards. Some of that is certainly urban heat island affect (more concrete = warmer nights). But it doesn’t explain why Bush, College Station, Galveston, and Hobby have all had top 20 or 30 hot summers every summer since 2016 (with the exception of 2017 in Galveston). That is likely because the atmosphere is warming, the Gulf is warming, and it’s able to hold more moisture and keep nighttimes much warmer than usual.
–Matt
Q: Are the CenterPoint Energy weather stations available to the public? If so, how do I locate and see the one near me?
A. Yes they are!
All the data from the sensors is being pushed out publicly through a company called “Synoptic,” which acts as a data source for various sources of weather observation data. The data can be accessed through a NOAA website (that’s a fantastic resource beyond just CNP weather stations). Within the Weather & Hazards data viewer, you’ll be presented with a buffet of sites you can choose from. These are not just CenterPoint weather sensors, but they include everything from Harris County Flood Control to Union Pacific Railroad to major airport sensors like at Bush and Hobby. You’ll have to click around a bit to find a CenterPoint one, but it’ll be a number 1-100, a location name, and then a suffix of CE. You can toggle the variable you want to see, including wind gusts, dewpoint, or rainfall, among others. There’s even a historical data mode on this site if you want to see observations from a particular date and time. It’s just a great site to bookmark!
NOAA’s Weather & Hazards Data Viewer. Click on a station to see its name. You can change the data you want to see at right. Bookmark the historical observations (3 day/7 day in the pop up bubble) for quick access to a site’s latest observations in the future. (NOAA)
There are also links to 3 day and 7 day histories as well. Those can be bookmarked for real time access updated every 10 minutes (such as this one for Sugar Land), and I would encourage you to bookmark the ones from any source closest to your house!
–Matt
Q: I live in Tomball off Texas 249/99 and we have had some intense storms Monday evening and Tuesday morning. It got so bad Monday evening that I got my family in the bathroom as winds had to be 40-50mph and were getting quarter size hail. The same thing happened this morning to where the wind was so intense that we had trees down in our neighborhood. I looked on my radar app and at the time, there was not even a Special weather statement. Later on they did issue it after it had passed through. I have seen storms that were severe warned that were much less intense. How a storm can be that intense and the NWS didn’t have any warning on it?
A: I’ll give you a good example of this. I am assuming that your experience was during the storms we had near the end of August. One of them produced a 66 mph wind gust at Brazos Bend State Park (from a CenterPoint sensor actually!) at 5:10 PM on August 21st.
A rather innocuous looking storm that produced near 70 mph winds on August 21st at Brazos Bend. (RadarScope)
Looking at radar, I’m not especially close to issuing a warning on that storm based on what we see above. One issue with Houston is that we are such a sprawling city that we actually have some pretty healthy data gaps when storms push through the area. Radar is critical, but it is also imperfect sometimes. Even the higher resolution and slightly closer Hobby Terminal Dopper Weather Radar showed winds of only about 35 mph in the above example. No indication whatsoever that this storm is producing 60 to 70 mph winds, but it is.
So there are instances where storms can (literally) fly under the radar. The radar beam up your way is shooting up to around 3,500-4,000 feet above the surface. So there is a chance that in those cases it was missing what was occurring closer to the ground.
It’s also not granular in time, either. Periodically, something will happen with a storm where it does its dirty work over the course of a minute or two, and it could happen in between the 2 to 4 minute radar scans we often get. Also, storms here tend are often what we call “pulse” storms: They ramp up quickly and ramp down just as quickly. You can literally go from a shower to a 50 mph hail-producing storm in the course of minutes. If I am correctly recalling the day you’re discussing, those storms were in fact remarkably quick to rev up. NWS did issue warnings, but there was a bit of playing from behind going on because of the nature of those types of storms.
But the reality is that until we get to more substantial radar coverage at more granularity than we’re currently capable of right now, there will occasionally be a miss like this from time to time. It’s the nature of uncertainty. It’s also a good reminder that if you see something, report it! Send it to us, the NWS, or your favorite local meteorologist. We’ll try to make sure it gets to the right people.
