There’s something about fall in Houston that feels a little different from the rest of the country. While much of the U.S. enjoys crisp mornings and sweater weather, we’re still sipping our pumpkin spice lattes in 80° heat and trying not to complain too much about it. For us, it’s not about the leaves changing color; it’s about waiting (sometimes impatiently) for that first real taste of cool air.
But beyond the weather, it’s worth remembering what the start of fall actually means. The autumnal equinox isn’t about temperatures or leaves; it’s about the Earth’s journey around the Sun. Thanks to the Earth being tilted 23.5° on its axis, we experience seasons. Without that tilt, there wouldn’t be a “fall” to look forward to ever in Houston.
The autumnal equinox doesn’t really have anything to do with temperatures, though we often notice lower temperatures arriving around this time as the Sun’s direct rays shift farther away from us.
The first day of fall:
This year, the equinox happens on Monday, September 22, at 1:19 p.m.
That’s the exact moment when the Sun’s direct rays shine over the equator, marking the official start of fall. The word “equinox” comes from Latin and means equal night. While Houston doesn’t get a perfect split of 12 hours of daylight and 12 hours of darkness on this day, it’s pretty close: sunrise will be at 7:10 a.m. and sunset at 7:17 p.m. And here’s something neat: on the equinox, the Sun rises exactly due east and sets exactly due west.
Now, here’s a detail many people don’t realize: the Sun isn’t just a single point in the sky; it’s a disk. By definition, then, sunrise occurs when the top edge of the Sun first appears above the horizon, and sunset is when that top edge slips below it. That small distinction gives us an extra 2–3 minutes of daylight each day. Add in the fact that Earth’s atmosphere bends light, making the Sun visible even when it’s technically below the horizon.
The equilux:
The equilux, the day when daylight and darkness are closest to being equal, comes a few days after the equinox. This year, in Houston, it falls on Friday, September 26, when the Sun will be above the horizon for exactly 12 hours, 0 minutes, and 22 seconds.
Now, about that cool weather we’re all waiting for:
Since September 10, we’ve been stuck with highs in the mid-90s, and while we keep hoping for that first real cold front, it won’t arrive until we see a major weather pattern shift. Until then, highs in the 90s will stick around. So the big question is: when will that finally change?
If you look at the graphic above, you’ll see that Houston’s first “real” cold front typically arrives in October. Sometimes it sneaks in as early as September, other times it holds off until November, but more often than not, October is when we finally get that first true taste of fall.
Our temperatures here are shaped far more by Gulf water temperatures, wind direction, humidity, high pressure, and the timing of cold fronts. Notice what’s missing from that list: the Sun’s heat. At this time of year, the Sun isn’t the main driver of our day-to-day weather.
As we move closer to winter, though, the angle of the Sun’s rays does start to play a bigger role. Here’s a look at the average highs from September 21 to December 14.
There is a cool front showing up in the 10-day forecast. It’s not the kind that will bring a big temperature drop or a lasting break from the humidity, but it will give us a brief taste of relief.
After storms move through on Wednesday, Thursday should feel noticeably nicer, before the humidity and temperatures quickly climb back into the 90s on Friday