A closer look at this summer’s heat in Texas, especially at night

The forecast is unmoved by the pleas of those of us looking for change. Simply, there is no realistic opportunity for relief showing up in modeling over at least the next week and perhaps 10 to 12 days.

The forecast from the National Blend of Models may be running a degree or two too hot at times by day, but the more important thing here is that there is no meaningful break in heat showing right now. (Weather Bell)

Here are rain chances over the next 7 to 8 days based on our interpretation of the European and GFS modeling:

The only day right now that appears to have a potentially mentionable chance of rain is Sunday, mostly east of I-45 and north of I-10. And even that’s not exactly a great chance.

There is one wrinkle in the forecast, and that comes on Sunday. A disturbance tracking into the Great Lakes may help erode the northeastern periphery of the ridge of high pressure juuuuust enough to perhaps allow for a weak disturbance to set off a few showers or storms from the northwest.

What meager rain chances we do have through next week are almost entirely confined to Sunday, isolated, and east or northeast of Houston. (NOAA)

This seems most likely to occur in Louisiana, but I would say if you live in Liberty County or closer to the Beaumont area, your chances look marginally better than zero for a cooling downpour on Sunday.

But other than that, there’s no reason to make this forecast more difficult than it needs to be. Roughly 100 during the day, roughly 80 at night, copy, paste from now through late next week. Heat Advisories are likely most days with at least a slight chance of us getting put back under an Excessive Heat Warning again at some point. Is there a chance something unforeseen presents itself before next weekend to help cool us a bit? I guess so, but I don’t see where that comes from right now. So expect another week of the same.

It’s the nights that hurt

Throughout this long hot summer, currently the 6th hottest on record, we have set a total of zero record high temperatures at Bush Airport. But we’ve managed to set (or tie) 10 record warm minimum temperatures as of yesterday. How have other parts of Texas fared?

With the exception of San Angelo and Corpus Christi, every major south, central, or west Texas city has set or tied more warm nighttime records than daytime highs. (Data from NOAA)

Most places have seen more nighttime low warm temperature records than daytime record highs in Texas. I omitted cities in the Panhandle and East Texas, as they’ve generally seen a bit less heat versus the south, central, and western parts of the state. Del Rio has had a hellacious summer, with 40 percent of their nighttime warm low records since June 1st set or tied this summer alone. Dallas and Houston stand out as the only two cities with no record highs (officially). Dallas largely escaped the worst of the June heat. If we take a look at this chart in a month, I expect that we would see a continuation of this trend of nighttimes being worse relative to normal than days.

Let’s look at this another way. The magic number in Texas for a really gross overnight is about 80° or so. Here is a look at how many 80° nights have occurred in 2023 so far (plus what’s forecast through next Thursday), compared to the annual record for nighttime lows of 80 or warmer.

Both Midland and El Paso should exceed their previous annual record for nighttime lows of 80 or warmer by next week. Del Rio, Austin, San Antonio, and Houston are getting closer. Other cities have a longer way to go but almost all are in the top 5 or 10 years on record already. (Data from NOAA)

In San Angelo, Abilene, and Dallas 2011 remains the benchmark summer for nighttime lows of 80 or warmer. Given the relatively cooler June, Dallas has a very long way to go. With more heat, San Angelo or even Abilene could come closer, however. Houston’s record of 26 overnights of 80 or warmer was originally set in 1962, but we should be only 5 days away from matching that by this time next week. For El Paso and Midland, their previous records look to be toast. El Paso’s was set in 2020 and Midland’s occurred previously in 2011. Austin and San Antonio should not be terribly far away from breaking their records for most 80 degree nights. Austin’s record was set in 2019 and again in 2020, while San Antonio’s stands from 2010.

Why does this all matter? Because heat becomes an exacerbated health and infrastructure issue when we do not cool off at night. Air conditioning units have to work harder. If poor climate controlled homes don’t cool down properly, then people (especially the elderly) become more vulnerable to heat illness. You’re simply being exposed to hotter temperatures for longer stretches of time. This is why we emphasize checking on the vulnerable. Don’t forget pets too.

The reason for so many record warm lows outpacing record highs varies from place to place. Some of it is attributable to the urban heat island effect and population growth and sprawl. Locally, the warm Gulf is likely a contributor as well, helping to increase humidity and raise the “floor” that temperatures can feasibly drop to overnight. But it does not explain these extremes entirely. Warming nights (and the warming Gulf) firmly fit the science behind climate change. Yes, that’s part of the reason too. When you put it all together it is making for a pretty rough summer, even by our hearty Texas standards.

Excessive heat continues, and despite what your weather app says it’s not going to rain

Good morning. Since the forecast is pretty much unchanged—expect very hot and sunny weather for the foreseeable future—I want to briefly address a question I’ve received several times. And that is, why does Apple’s weather app consistently show a 30 to 50 percent chance of rain for the next several days?

A screenshot from my iPhone this morning.

Now if we’re to believe this forecast, there is a 30 percent chance of rain today, and a healthy 50 percent chance on Friday. And since Apple makes some pretty amazing hardware and software, it’s difficult to doubt Apple. But in this case, the Apple weather app is just massively wrong. The rain chances today are not 30 percent, but rather about 3 percent (as the Space City Weather app, which is not flawless I will say, suggests). And while I would dearly love to be wrong, a 50 percent chance of rain on Friday is preposterous.

This has been a persistent forecast within Apple’s weather app for awhile now. I honestly don’t know why this is occurring because there is no credible modeling suggesting this will happen, and it entirely defies everything I know about meteorology given the current pattern. My only thought is that while AI and automated forecasts are promising, they still require some human curation. Which we endeavor to provide.

Thursday

Meanwhile, back in the real world, we’ve got another excessive heat warning today, with high temperatures of about 100 degrees and a heat index pushing past 110 degrees. The only notable change is that winds out of the south will be a little bit more pronounced, up to about 20 mph. Lows tonight will drop to around 80 degrees.

Friday

Slightly drier air could push us out of “excessive” heat territory into a simpler heat advisory, but it’s still going to be dang hot. Rain chances are in the sub-5 percent category.

Next week looks hot as well. (Pivotal Weather)

Saturday and Sunday

The weekend will be sunny and hot, with rain chances near zero percent.

Next week

Honestly, there’s not a whole lot of change in sight for next week as a ridge of high pressure remains dominant over our weather. Maybe, if I squint, there’s a bit of optimism for returning rain chances by the end of next week. But it’s not a bet I’m placing with confidence.

Excessive heat warmings return as high pressure thickens

Good morning. Our overall pattern remains more or less the same, with high pressure leading to very hot weather for the next week, and quite possibly beyond. Today and Thursday could bring the worst of the weather, with very high dewpoints contributing to the heat.

We see this in the forecast for “wet bulb globe temperatures,” which factor in several variables to provide an overall guidance for how uncomfortable conditions will be. (I discussed these a bit more in depth on Monday) Temperatures for today and Thursday are forecast to be above 90 degrees, which means our weather will be extremely uncomfortable.

An excessive heat warning is in effect for much of the metro area today. (National Weather Service)

Wednesday

There is not much to say beyond the fact that temperatures will reach about 100 degrees, with sunny skies and stifling humidity, and modest southwest winds at about 10 mph. Lows tonight will drop to around 80 degrees.

Thursday

Conditions will be much the same, although southerly winds may be a little higher, at 10 to 15 mph.

Friday

With the influx of slightly drier air and winds gusting up to 20 mph, conditions might be slightly more tolerable outside. But temperatures will still be really hot, about 100 degrees for much of the region away from the coast.

Wet Bulb Globe Temperatures may moderate slightly heading into the weekend. (Weather Bell).

Saturday and Sunday

Yes, the weekend looks sunny and hot.

Next week

A series of atmospheric disturbances will push through the area later on Sunday and on Monday; and were we not under the influence of high pressure, these are the kinds of systems that would bring us a healthy chance of rain. However, due to generally sinking air over the region, I’d rate the chance of these disturbances at producing rain at about 10 percent. Still, it’s something to watch, as most of the rest of the forecast just looks to be unendingly hot, humid, and rain free.

It will remain persistently hot and sunny for the foreseeable future

This is bad for business, but as usual we’re going to be honest with you here. For the next few days, at least, you really do not need to check the daily forecast here at Space City Weather. We are in a persistent pattern of high-pressure dominated weather that will last for at least the next week, and quite possibly longer. This high anchored over the southwestern United States, is not going anywhere, any time soon.

High pressure will remain anchored over the southwestern United States for awhile. (Weather Bell)

The conditions that we’re going to experience through the middle of July are not atypical, per se, for this month. It is summer in Houston. It is hot. But the heat is going to be tenacious, with daily temperatures 3 to 5 degrees above normal, and without any let up. Every day is going to see high temperatures in the upper 90s to 100 degrees. Lows will barely fall to 80 degrees. And while there is a very slight rain chance this afternoon, overall chances will be 10 percent or less on most days. The entire metro area is under a heat advisory and will remain so for the foreseeable future.

Tuesday

Skies will be mostly sunny with high temperatures near or reaching 100 degrees for most of the region away from the coast. Winds will be light, at 5 to 10 mph from the southwest. There is perhaps a 10 or 20 percent chances of showers and thunderstorms this afternoon, but most areas will not see anything resembling rainfall. Lows tonight will be around 80 degrees in Houston.

Wednesday

A similar day, albeit with even lower rain chances. Look for highs in the upper 90s.

Above-normal temperatures are likely to persist through next week. (Pivotal Weather)

Thursday until ???

From Thursday, through the weekend, and at least into the middle of next week we are looking at hot and sunny weather, driven persistent high pressure. This means mostly sunny skies, highs near 100 degrees, and warm, humid nights. It is possible this pattern breaks somewhat by the middle or end of next week, but I would not hold my breath.