In brief: Today’s post discusses an upcoming pattern change what will bring some rain midweek, and then some modestly cooler weather through the weekend. It won’t feel like fall, precisely, but it won’t be August-like either.

Fall, finally?

It is fitting that the Autumnal equinox comes on Tuesday, when precisely at 1:19 pm CT the Sun will move directly over the equator. Why? Because some semblance of almost fall-like weather is on the way for the Houston region. The last 10 days, or so, have felt very much like late summer in the region, with a string of daily high temperatures at Houston’s official monitoring station hovering between 92 and 95 degrees.

We have a couple of more warm-ish days before a weak front arrives mid-week. This won’t bring that much cooler air—although it will bring some—but it will knock some of the humidity out of the lower atmosphere. As a result temperatures will feel a little more comfortable. We are likely to see more 90-degree days in the weeks ahead, but I don’t think we are going to see any more prolonged stretches of highs in the low- to mid-90s.

Monday and Tuesday

These days should be similar, which is to say high temperatures generally in the vicinity of 90 degrees to the lower 90s, with plenty of humidity. Skies will be mostly sunny. Areas along and south of Interstate 10 have perhaps a 40 percent chance of seeing a passing shower or thunderstorm, while areas further inland probably have a somewhat less (but non-zero) chance). Winds will be modest, from the south-southeast, and nights warm, with lows in the upper 70s. All in all, it will be pretty sticky outside.

Wednesday

A cool front will approach the area on Wednesday, and this combined with surging moisture levels in the atmosphere should produce widespread showers and thunderstorms. Most of the area probably will pick up 0.5 to 1.5 inches through the period of Thursday morning, but the majority of this rain probably will come on Wednesday and Wednesday evening. This will be another warm and humid day before some slightly drier air begins moving in over night.

Thursday

I think we’ll see some lingering showers on Thursday morning, as it will take some time for the front to amble off the coast. By the afternoon we should see clearing skies and high in the upper 80s. Lows on Thursday night should drop into the 60s for all but areas near and along the coast.

Friday, Saturday, and Sunday

We still have some questions about the details for this weekend, because it’s just not clear how much oomph the front will have, but we can be confident in the big picture. Skies this weekend should be mostly sunny, with highs in the upper 80s to 90 degrees, and modest humidity. Nights will be a bit cooler, probably in the upper 60s. Some very slight rain chances likely return to the forecast on Sunday or Sunday evening. All in all, it looks like a warm, but fine weekend.

Next week

Most of next week looks sunny, with highs around 90 degrees and nights in the lower 70s. It’s not exactly going to be summerlike in Houston, with slightly lower humidity levels, but it won’t exactly feel like fall either. For me it always feels like we’re sitting in the cold front waiting room at this time of year.

In brief: Mainly quiet, pollen-ridden weather through tomorrow in Houston, followed up by more scattered-type showers and storms Sunday through Tuesday. A cold front that’s more like a humidity front continues to look plausible around midweek next week. The tropics remain quiet for us.

Today & Saturday

Our late summer slog continues with hot days, warmer than normal nights, and generally high humidity (though at times it feels decent outside at least). Isolated showers are possible today, and we may see isolated to scattered showers or a thunderstorm tomorrow. Overall, nothing too bad. Temperatures will be in the low-90s for highs.

An ozone action day is in effect again today. For most people this will not be an issue, but for those of you in sensitive groups, try to avoid being outside except early and late in the day. Also, for those of you (like me) that have had the sniffles lately, there’s a good chance that ragweed is the culprit.

The typical autumn nemesis.

Sunday through Tuesday

Scattered showers and thunderstorms should be the name of the game beginning Sunday. While this will still be a patchwork type rain setup, a few more folks should begin to participate each afternoon. Expect continued highs in the low-90s but perhaps some slightly cooler afternoons at times due to the showers. Lows will remain mostly in the 70s.

Wednesday front!?

Eric has mentioned the potential of a cool front next week, nothing spectacular but a potential notable change for a couple days. That remains very much on the table today. The timing is a bit suspect, but sometime in the Wednesday or Thursday timeframe, it appears that a weak front will drop south into the area, bringing the potential for scattered to numerous thunderstorms for a short time. Behind the front, we’d turn a little cooler and a lot less humid to close out the week.

You can see the European model forecast of dewpoint for midweek, showing a distinct drop in dewpoint levels on Wednesday evening into Thursday and Friday. This is more of a humidity front than a cold front, though the lower humidity should translate into a chance at widespread lows in the 60s by Friday morning perhaps. With the Autumnal Equinox on Monday afternoon, we do see signs of fall sprinkling the forecast.

Tropics

Gabrielle is slowly building in the Atlantic, but that’s where it will stay. Another wave behind Gabrielle has some development risk, but that also looks to stay in the Atlantic. Is there anything to focus on for Houston? Nothing specific. There’s a general trend, particularly with AI models to try to spin something up in the northwest Caribbean in about 10 days, but that’s not supported much in the traditional physics-based models.

So this will be a good test for AI modeling: Are they capable of “seeing” a tropical genesis risk earlier than traditional models. In truth, earlier this season, when AI models were quite a bit spicier than traditional models at genesis forecasts, they tended to fail the test. This may also be a case of AI modeling being overzealous for some reason, but it’s something we’ll watch at least. Only 2 known hurricanes have had legitimate hurricane impacts on the Houston area after next week: Jerry in 1989 that hit Galveston and a storm that took a similar track to Beryl from last year that hit in 1949. History is on our side after next week, but as always, we will continue to watch.

For the record, come October we are more likely to be impacted by remnants of Pacific storms that bring heavy rain risk than a direct impact from the Gulf. That can bring its own set of problems, so forecasters stay vigilant deep into October.

In brief: In today’s post we dive into the precipitation Houston recorded this summer. Most of the region got significantly less than normal, but we’re not in a drought. Why? We also dig into the forecast which indicates continued warm-to-hot temperatures and an increase in rain chances ahead.

Autumnal equinox looms

Alright, I’ll allow that it does not really feel like summer should be ending soon, especially with a 95-degree temperature reading at Bush Intercontinental Airport on Wednesday afternoon. And in reality, I am sorry to say, I don’t think we are done with heat just yet. Nevertheless, by next Monday we will come to the Autumnal equinox, which by some reckonings marks the beginning of fall in the Northern hemisphere. Note that we already passed into meteorological fall on September 1.

As I noted yesterday, we have had a fairly dry start to September. Since there is not a whole lot else to talk about today, and because the month so far has been dry-ish, I thought we might take a look at how the region did precipitation-wise over the course of the summer. As you can see in the map below, showing “percent of normal” rainfall over the last 90 days, the vast majority of the Houston region has received 50 to 90 percent of normal rainfall during the hottest part of the year.

So why aren’t we in a drought? (Really, we are not). The answer is two-fold. We had some really nice rains in late spring that positioned our soils well for the summer months. And then, while conditions were drier than normal across Houston in July, August, and September, we did have periodic rains that brought a few inches at a time. So if you add that up, we’ve come through summer alright. Things have gotten fairly dry in parts of Houston in the last week, but I’m hopeful that we’ll see some decent rains next week to get us back on track.

Thursday

Yes, you can expect pretty much the same weather today that we’ve experienced for about the last 10 days: highs in the low-90s in central Houston, with slightly hotter temperatures further inland, and slightly cooler closer to the coast. Skies will be mostly sunny, with a slight chance of some showers and thunderstorms popping up this afternoon. Overnight lows will fall into the mid-70s.

Friday and Saturday

More of the same.

Sunday

By Sunday the pattern starts to become a little more unsettled, such that we might see rain chances of 20 to 40 percent by the afternoon. This may help to hold high temperatures down to about 90 degrees in Houston. If you have outdoor plans I don’t think these showers will prove to be too disruptive, as they should be scattered and brief.

Next week

Our pattern really should shift some next week, with better daily rain chances beginning by Monday. Overall accumulations next week will probably be on the order of 1 inch, but also there will likely be a great deal of variability in that. Modestly more clouds should keep highs on the order of 90 degrees, although rainier days may top out in the upper 80s. A weak front may back door its way into the region later next week, but that is far from certain.

In brief: Houston will see plenty of sunshine through the weekend, but we will also start to see some slightly better rain chances. By later Sunday or more likely Monday, the pattern will change more noticeably, with increased clouds and the potential for widespread showers.

A slowly changing pattern

With one or two exceptions, most of the first half of September has seen sunny days with near zero rain chances. This pattern, especially over the last 10 days or so, has seen high pressure dominate our region’s weather. This is now slowly beginning to change, and by this weekend an upper-level system will shake things up. As a result we will see modest rain chances over the next couple of days before the potential for more widespread showers by Monday, which perhaps will persist for much of next week.

Wednesday

Today will bring sunny skies into the region with our typical temperatures in the low 90s for much of the central metro area, with inland areas getting a little warmer than this and the coast remaining a little cooler. There is some support in high resolution models for the development of scattered showers, and perhaps a few isolated thunderstorms, between about 3 pm and 7 pm this afternoon and early evening, before the loss of daytime heating. Lows tonight will drop into the mid-70s for most locations.

Thursday and Friday

Both of these days should see sunny skies. I do think high temperatures may be 1 or 2 degrees cooler, but it will still be hot during the afternoon. Rain chances both days look a bit lower, perhaps on the order of 10 to 20 percent.

Saturday and Sunday

Most of the region should see highs of around 90 degrees this weekend, with mostly sunny skies. However, there will be a slight chance of some showers and thunderstorms as the atmosphere starts to become more unsettled. I think the more widespread rain chances will probably hold off until Monday, but I’m not sure of that. For now I’ll go with about a 20 percent chance of rain on Saturday, and maybe 40 percent on Sunday, but these are kind of fuzzy at this point.

Next week

By Monday-ish we should see an atmosphere more broadly supportive of showers and potentially some thunderstorms. This should set the tone for next week, with something like a 40 to 60 percent chance of rain each day. This should also limit high temperatures to about 90 degrees, or less, on a daily basis. As of yet there’s no strong signal for the next cold front, but maybe something weaker may back door its way in later next week. We’ll have to wait and see.