Finally, a hint of fall in the forecast for Houston. And maybe some rain, too.

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.

The last 11 days have been a little hotter than normal for September. (National Weather Service)

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.

NOAA rain accumulation forecast for now through Wednesday night. (Weather Bell)

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.

After our latest dry spell, how did the greater Houston region do this summer with rainfall?

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.

It’s been slim pickings on the rain front this month. Dark green lines indicate rain, red is records. (National Weather Service)

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.

Percent of normal rainfall over the last 90 days.

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.

NOAA rain accumulation forecast for now through next Wednesday. (Weather Bell)

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.

Modest rain chances reenter the forecast, with a pattern change ahead

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.

Today is probably the last day, for awhile, that much of the region pushes into the mid-90s. (Weather Bell)

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.

We will see an increased likelihood of rain next week. (Pivotal Weather)

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.

The tropics are waking back up, but hurricane season is nearing its end for Texas

In brief: Today’s post discusses the state of the Atlantic tropics, which are waking up after an uncharacteristic snooze to start September. We also talk about the persistent pattern of late summer weather here in Houston.

State of the tropics

After the Atlantic tropics have slumbered for nearly three weeks (Tropical Storm Fernand gave up the ghost on August 28), we are close to seeing the formation of a new named storm in the open Atlantic. This would be Gabrielle, and it likely will become a hurricane over the next few days. This storm could well threaten Bermuda early next week, but it otherwise is unlikely to approach any landmasses.

The Atlantic tropics are waking back up. (National Hurricane Center)

Beyond this storm there is another system behind it, a tropical wave that is just now moving off the coast of Africa and into the eastern Atlantic Ocean. The global forecast models are divided about whether this system will develop, and for now the National Hurricane Center gives it about a 20 percent chance over the next week. This is something to watch to be sure as we are in the middle of September, but nothing to be really concerned about at this point.

Probability of a tropical depression forming during the next 10 days. (European model)

The window for hurricanes to strike Texas is closing, but it is not closed yet. I want to wait another week or 10 days before making that call. The only thing I’m really concerned about now, and to be clear this is a very mild concern, is the potential for something to develop in the western Caribbean Sea or southern Gulf, and for such a system to move north toward the state. But again, this is a low probability event.

Tuesday

If you’re looking for new and exciting changes with Houston’s forecast, I’m sorry to disappoint you. Houston remains locked in the same late summer pattern of warm days, mild nights, and mostly sunny skies. It does look as though we will start to see some better rain chances by early next week, but for the most part the likelihood of seeing rain for the next few days will be on the order of 10 or 20 percent. Highs today will be in the low 90s in Houston, with far inland areas perhaps seeing mid-90s, and the coast topping out around 90. With dewpoints in the 60s the humidity will be up there, but it won’t be “summer sticky.” Winds will be light, generally from the east. Lows tonight will drop into the mid-70s.

Wednesday, Thursday, and Friday

And so it will go for the rest of the work week. Highs might be a degree or two cooler as we approach Friday, but most of the region should still reach the lower 90s, with mostly sunny skies. Nights remain in the mid-70s. Rain chances are low, but non-zero.

Daily highs should slowly subside. (Weather Bell)

Saturday and Sunday

High temperatures this weekend will be about 90 degrees, so a smidgeon cooler, but I think that will be accompanied by a slight rise in humidity. There are some chances for isolated to scattered showers, perhaps on the order of 20 to 30 percent for both days, with the better chances toward the coast. But these should be fairly short lived, if they develop. Skies should still be mostly sunny, most of the time.

Next week

Our pattern next week may finally shift a little. Highs are likely to be around 90 degrees, with better rain chances on Monday (maybe as high as 50 percent?) We could see partly sunny skies for much of next week, with scattered daily showers. I’m still not seeing a strong signal for the next cold front, so late summer will probably be sticking around for awhile.