Matt Lanza

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.

We are not quite done with rain chances in the Houston area yet as potent summer heat looms

Yesterday saw some locally hefty rains across the area. We picked up anywhere from 1 to 4 inches of rainfall between Pearland and Westchase, with another bullseye out west of Cypress along 290 into Waller County.

Radar estimated rain totals were as high as 4 inches in parts of Waller County and close to that near the intersection of the Westpark and the Beltway. (NSSL)

Areas just south of The Woodlands saw 2 to 3 inches of rain as well. Even Matagorda Bay (not shown above) saw about an inch or more in most the area. We are not yet done with the rain, though we do not believe today will play out quite as yesterday did.

Today

We’re starting the day off with an area of rain sitting near Matagorda Bay and just a few showers in and around Galveston Bay and the island.

Heavy rain is impacting the Matagorda Bay area this morning, with just a few showers and rumbles of thunder around Galveston Bay. (RadarScope)

As the day goes on, look for more scattered thunderstorms to develop across the area. The highest chances will be south and east of about Cypress. So much of the area will see showers or at least hear thunder again. Those that see showers today could see as much as an inch or two of rain, while others will see next to nothing. Look for generally low 90s and light winds (except localized gusts in storms).

It feels like we have one or two more decent chances at rain today and tomorrow before the spigot is basically shut off.

Saturday & Sunday

If you have weekend plans, you will probably be fine. But there will certainly be thunderstorms in the area. Look for about a 30 to 40 percent chance of showers and storms on Saturday, followed up by about a 20 percent chance on Sunday. Outside of showers, look for sun, clouds, and slowly increasing temperatures. We’ll be in the low to mid-90s tomorrow and firm mid-90s on Sunday. Morning lows should be in the 70s on Saturday before back closer to 80 degrees on Sunday morning.

Early next week

Rain chances don’t quite go to zero to start next week, but they will drop off to the 10 to 20 percent range on Monday and Tuesday. As that occurs, look for temperatures to warm into mid to upper-90s, with morning lows near 80 degrees. It will begin to feel rather uncomfortable with peak heat index values over 105 degrees.

We expect to start seeing the question “when will this round of heat ease up?” soon, and unfortunately we don’t have a clear answer right now. (Weather Bell)

Heat returns

By the time we get to Wednesday, look for high temperatures near 100 degrees, give or take a couple, with morning lows around 80 degrees. The difference between this heat wave and June’s heat wave will be noteworthy. In June, the high pressure setup directly over northern Mexico or Texas, and we just baked with extreme (for June) heat. This time around, it looks more like a traditional summer heat wave, with high pressure centered over the Desert Southwest. It will strengthen and expand to a point where we see just a lot of generically “hot for July” weather in southeast Texas but probably not extreme heat. If the June pattern had recycled this time around, we’d probably be talking 102 to 105 degrees every day. Instead, we’re probably talking 98 to 102 degrees, which while quite uncomfortable is not terribly uncommon in July.

That said, I fully expect heat advisories to re-enter the chat by early next week. As this will again be a potent, long-duration period of high heat and humidity, heat precautions should be taken as they were in June.

One more blazing hot weekend before changes emerge across Texas

Today marks our 18th straight day of heat advisories or heat warnings. We close June on the same note we’ve been singing (with rampant falsetto) since mid-month. Heat waves are often judged by how many temperature records are broken. So have there been many temperature records broken the last couple weeks? The answer is not really.

For the month of June, through yesterday, we set or tied a total of zero record highs at Bush, two at Hobby, none at Galveston, and none in College Station. Despite the general lack of record highs, we’ve managed to reach a frequency and consistency of 110+ heat index values that is rare for this region. It’s why we emphasized that this would be an abnormal heat wave for us.

Nighttimes have been more intriguing, with seven record warm minimum temperatures set or tied at Bush, seven at Hobby, none in Galveston, and five in College Station. The lack of any nighttime relief really contributes to defining how rough this has been.

Fortunately, we are past the peak of things it seems and we can start discussing how this will change.

Today and tomorrow

More of the same. Sunny and hot, with highs in the upper-90s and lows near 80, and a near zero chance of rain. Heat advisories will likely be needed for one more day tomorrow.

Sunday & Monday

This will be the transition period. Look for generally more of the same again. Expect mid to upper-90s for highs and upper-70s to near 80 for lows. However, the new wrinkle on these days will be rain chances. Sunday looks meager at best and mostly south and east of Houston. Let’s call it a 5 to 10 percent chance of a shower Sunday. That’s better than zero, but the odds remain stacked against you. By Monday, that rain chance should improve to 20 percent or so. Better!

Rain chances creep up on Sunday and Monday, with a slightly better chance on Tuesday. Most places will not see rain through Tuesday, however. Many will see rain at some point Wednesday through Saturday.

Fourth of July Tuesday

This will be the trickiest day, because I could see our rain chances fizzling here or being something like 10 to 20 percent again. Or, coverage could increase a fair bit during the afternoon hours, with not everyone seeing rain but some folks needing to scurry indoors for a time. Let’s call it about a 30 percent chance of rain on Tuesday afternoon, with the highest odds south and east of Houston; higher chances than Monday but still relatively low. As of now, I’d expect that most evening events will be able to go off without issue.

Independence Day temperatures will top off in the mid-90s for Houston. (Pivotal Weather)

Look for mid-90s or a little hotter on Tuesday with evening temperatures generally dropping back into the mid to upper 80s for fireworks or other activities.

Wednesday through Friday

We get a big boost in moisture beginning Wednesday, and this should translate to more scattered to numerous showers and storms through the late week period. While it’s tough to pin down the exact timing of rain chances each day, I would say that the chance is at least 50 to 60 percent on all three days. So there’s a good chance your neighborhood should see at least some rain at some point later next week.

Rain totals through next Friday actually exist! Take these numbers as an approximate average. Some will see less, others more. (Pivotal Weather)

Due to the clouds and showers, we should see high temperatures ease back into the low (!) or mid-90s at worst, more seasonable for early July. Nighttimes should be more firmly in the 70s. Eric will be back in the saddle Monday. Until then, stay cool!

A break in the excessive Texas heat is in sight

Alright, I’ve been covering Eric most of this week, and given the stability in the forecast, it’s been a little challenging to discuss much, which has actually kept the posts pretty short and sweet! We’ll do that again today, but I want to focus more on next week.

Today through Sunday

More of the same: Sun, heat advisories or excessive heat warnings, and very minimal rain chances. Highs near 100 or in the upper-90s. Lows near 80 each day.

Moorrrrreeee heat! Thursday will again see highs near 100 degrees. (NWS Houston)

I suppose Sunday may see a slightly better chance for a stray shower along the coast, but even that looks mediocre at best right now.

Monday & Tuesday

With the holiday weekend perhaps being four days for many of you, there will be obvious interest in Monday and Tuesday’s forecast. What we know is that rain chances will not be zero on those days. However, the higher rain chances next week look to hold off until Wednesday through Friday. Our shower chances will be about 10 to 20 percent on Monday and 30 percent on Tuesday, hopefully winding down in time for area fireworks displays. I don’t think anyone needs to alter plans for the Fourth, but it’s probably a good idea to think about a rain option, just to be extra safe, if only for a short period of time.

Our best estimate of rain chances through next week. We believe the highest coverage and probability of rain or storms will occur Thursday and Friday next week, which looks to be about 50% today.

Rest of next week

As we move beyond Independence Day, it looks as though we will ease into more of a classic midsummer pattern for Houston. It won’t be cool, but it will be noticeably less hot. We should see fewer and less regular heat advisories or warnings. Expect highs more into the mid-90s, near average for this time of year. Morning lows will be mostly in the 70s to perhaps near 80 at times. But each day will carry at least a 20 to 40 percent chance of scattered thunderstorms to locally cool things off. Rain chances should build into the end of the week, nearing 50 percent on Thursday and Friday before declining once more.