Matt Lanza

In brief: The main story over the next week will be heat, with high to periodically extreme conditions for the Houston area. Shower and storm chances will diminish but probably never get to zero. Saharan dust should show up this weekend before declining. And the tropics are busy with stuff to watch but no serious concerns for us at this moment.

Today through Sunday

As high pressure begins to expand over Texas, somewhat reminiscent of what happened last summer, the spigot should temporarily shut off here in Houston. We can’t rule out an isolated shower in the area, but the coverage of rain is going to diminish. The main story through the weekend will be heat. Heat advisories are in effect today and will likely be in effect tomorrow as well. Highs will be well into the 90s to near 100 in spots. Morning lows will be around 80 degrees.

Sunday will be interesting as a plume of Saharan dust arrives in Texas. We’ll see hazy skies which won’t help a ton with the temperature, but it may lead to a slight decrease in how bad it feels outside. Here’s the wet bulb globe temperature (WBGT) outlook for the next week, and you can see the slight dip on Sunday from “extreme” levels to “high” levels.

Remember, WBGT is a good, objective measure of how intense the combination of heat, humidity, wind, sun, and more is on the human body. Extreme levels, which we frequently hit last summer indicate heat where everyone should take precautions, even hardy Houstonians. High levels are more typical in Houston throughout summer. So, just take it easy this weekend.

Next week

The forecast is somewhat on autopilot for most of next week. High pressure should stay in tact, centered to our north or northeast most of the week, keeping us plenty hot, but never sending rain chances to zero. They will be quite low on several days though. Expect highs in the upper 90s to near 100 degrees with lows in the 70s to near 80 degrees; a very “high summer” feel for early July.

Fourth of July

At this point, it would seem that most plans should be good to go. We can’t rule out a shower, of course, but anything severely disruptive seems unlikely. Just make sure you’re hydrated (with water) and able to cool off. Evening festivities will probably see temperatures drop from the 90s into the upper-80s. Call it about a 10 percent chance of a shower or storm right now, but we encourage you to check back Monday for the latest.

Tropics

We continue to monitor Invest 95L, which is almost certainly going to become a depression or tropical storm by the end of the weekend. We have daily updates at The Eyewall, our companion site, and we will continue to provide those all weekend.

For now, we expect this to be a concern for the Lesser Antilles before it gets disrupted by land or the usual shenanigans present in the eastern Caribbean in early July. From there, all bets are off, but a general west or slightly north of west motion should continue toward Central America or the Yucatan. It is not a serious concern for us in Houston right now, but we’ll be watching it closely to see if anything changes.

The other system moving into the Bay of Campeche this weekend (Invest 94L) will move into Mexico with no impacts for us in Houston or Texas.

In brief: After a quiet weekend, rain chances pick back up Monday and Tuesday before potentially heavier and more widespread rain on Wednesday and Thursday. Tropical development in the Bay of Campeche will not directly impact Houston, but indirect impacts with rough seas, gusty coastal winds, and some tidal flooding will be possible.

Right out of the gate, we want to make sure people understand that next week’s weather is being driven by two entities: The first is the potential tropical system in the Bay of Campeche, which will not directly impact us. But the second will be the heavy rainfall on the north side, tangentially associated with it that will impact us. The latter continues to give us some forecast headaches, which we’ll explain below.

Today and Saturday

No issues are expected with plentiful sunshine. As always, a rogue downpour is possible in the afternoon, but much like yesterday it should be quick moving and very localized. Daytime highs will be in the low to mid-90s with elevated ozone levels as well, so poor air quality will be noticeable. Morning lows should be in the 70s tomorrow.

Sunday

For now, we expect much the same for Sunday, though a few extra clouds could begin to sneak in for the second half of the day, along with an isolated shower or downpour.

Monday & Tuesday

We expect scattered to potentially numerous showers and thunderstorms in the area on Monday and Tuesday afternoons, though it’s a bit soon to pin down exactly where these will be most likely. Think of the first couple days of the week as slightly juicier typical summer days. There could be a handful of stronger storms or localized heavy downpours. This should keep temperatures down a bit as well, mostly in the 80s to near 90 degrees.

Wednesday & Thursday

We are beginning to see decent model agreement that Tuesday night, Wednesday, and early Thursday will feature our highest rain chances, and with that will likely come some heavy rainfall. I think this is the timeframe where I would be watching closest for potential flash flooding. The trouble right now is that our models widely differ on where this occurs. Our typical physics-based models are focusing things on the entirety of the Texas coast, while our newer AI models favor Houston into Louisiana for the heaviest rainfall.

One other possibility in this scenario is that a lot of rain falls at the immediate coast or offshore, which ends up depriving inland areas of moisture. So there is at least a chance that we see a very sharp gradient of rainfall next week with high totals near Galveston and very manageable totals in Houston. Things should hopefully quiet down later Thursday and Friday, regardless.

Marine impacts

In addition to the rainfall, we will likely see some pretty considerable wind and wave impacts over the open waters next week. With rather sustained easterly or east-southeast 20 to 30 mph winds nearshore and 30 to 35 mph winds offshore, look for waves to begin to build to 8 to 10 feet over the Gulf by midweek. I would anticipate nuisance to minor tidal flooding issues as we hit high tide cycles on Wednesday and Thursday. We’ll want to keep tabs on this just because of the persistence of the onshore flow next week.

Bay of Campeche system

We continue to see about a 50/50 shot that a tropical system develops in the Bay of Campeche next week.

As noted above, this is related but separate from the rain we see next week. While development (low-end) is becoming more possible or likely, it is expected to quickly slide ashore in Mexico, so no direct impacts are expected on the Texas coast.

Beyond this, there may be another sloppy system that tries to develop the week of June 24th, but we have plenty of time to watch that. We’ll have more on next week’s rainfall situation over the weekend.

In brief: Humidity will inch back up this weekend as we continue with quiet, hot weather. Another cold front may make an attempt to arrive early next week, but whether it brings a big drop in humidity or just a modest one remains to be seen.

On Thursday, the dewpoint at Bush Airport fell to 64° during the peak of our daytime heating. That’s the lowest it’s been since May 19th. While it was plenty hot yesterday, it was at least a bit less humid than we’ve been dealing with. Any break you can muster in the humidity in summer is a good break here in Houston. And we may have some more of it to come.

Today

We’re expecting a very similar day today as we saw Thursday. A few spots will push the upper-90s this afternoon. Humidity will again be low-ish. Walking outside this morning, it doesn’t feel quite as nice as yesterday, but still not terrible for summer. Heat risk today will be minor to moderate across the area.

One side note: Because of so much sunshine, ozone levels will be high today, and there are air quality alerts for ozone posted. So if you struggle with that, be aware that today will be further unpleasant.

Weekend

The humidity will slowly inch back up this weekend. Look for more of our standard 70s dewpoints with daytime highs in the mid-90s. Rain chances look minimal to near zero on Saturday with ample sunshine expected. Sunday stands a slightly better chance of a brief, passing shower, more in the “it can’t be entirely ruled out” range of things. Morning lows should hold in the mid-70s, with slightly steamier morning conditions.

Monday

The forecast gets very difficult here. From a rainfall perspective, we aren’t expecting anything crazy, just a few showers or storms for now. We’ll keep watch. The tricky part comes with determining how much this cold front can punch through Houston. The GFS model really wants to send the humidity back south to Cancun, while most other model data shows perhaps a modest drop in humidity, maybe similar to what we saw yesterday and today.

I would lean toward the latter, but there is a world in which the former could indeed come to fruition. History and climatology favors the Euro and other models in this instance. But never say never. Perhaps we’ll come back with good news later this weekend or Monday. One can hope.

Rest of next week

After Monday, the week looks to be somewhere between average and slightly unsettled. We could see a few thunderstorms as a trough settles in over us and we end up placed on the downward side of building ridge to our west and southwest. Temperatures look very benign with generally low-90s and 70s for lows, fairly average for mid-June. We should see temps reach back to the mid-90s by late week or the weekend.

Tropics

Look for a post over at The Eyewall in just a bit that will discuss the potential of a system in the Gulf in about 10 to 14 days. I am not concerned about this from a “big storm” or Houston impacts standpoint. It’s still early in the season and model support is lacking. However, there may be something that tries to get going later next week or after Father’s Day. I’ll have that for you a little later this morning.

In brief: Strong to severe thunderstorms with gusty winds will push across the area through the morning. Street flooding and some scattered power outages are a good possibility. Additional storms are likely this weekend.

This morning

A squall line of strong to locally severe thunderstorms is moving into the area as we post this. Heavy rain, frequent lightning, localized street flooding, and wind gusts of 40 to 60 mph are a good bet as this pushes through.

While these storms are not quite as severe as what we saw back on Tuesday this week, this will likely set the day off on the wrong foot. It wouldn’t be the worst idea to delay your morning commute until these pass. Most wind gusts have been 35 to 45 mph recently as these pass, which is relatively standard for strong storms here. Still, given the area’s sensitivity of late, some scattered power outages may occur in parts of the area.

This afternoon

The morning storms will clear off to the south and east. Since the timing of these storms clearing occurs in the morning hours, the atmosphere may not have enough time to recover this afternoon. While I wouldn’t rule out additional showers or thunderstorms in spots this afternoon, the worst of the action will hopefully be confined to the morning. After a rain-cooled morning, temperatures should recover into the 80s this afternoon. Eric will update later today on any changes.

Tonight & Saturday

Look for additional rounds of showers and thunderstorms tonight or Saturday. The exact timing and location remain frustrating to us in terms of predicting. But we are not done yet, that much we know. Some model guidance has a fair bit of storm activity tonight and Saturday, though mostly not severe and rain-focused. But this will be a period we continue to watch for storminess.

Sunday

Support for thunderstorms should be about ready to exit starting Sunday. I still think there’s enough juice and disturbances left to fire off another round of storms around the area, along with heavy rain and perhaps gusty winds. But the hope is that these will become a little less frequent. Highs in the 80s to near 90 degrees, lows in the upper-70s.

Next week

Storms have tended to move around the periphery of a ridge of high pressure over Mexico that has provided them with absolutely punishing, extreme, record heat this month. As that ridge expands a little next week, we should see storms lift back to the north some each afternoon or evening. So favored areas will be north toward Huntsville or even north of there. We’ll see an uptick in temperatures with low-90s possibly shifting toward mid-90s by mid to late week.

The more noteworthy item for next week will be a disturbance or even some kind of cool front that arrives later in the week. If that happens and pushes off to our south and east as shown, there is the chance that we set the stage for much, much nicer, less humid weather for a couple days next weekend. I would not rule out a morning low in the 60s in the Houston area at this point next Friday or Saturday. It’ll still be plenty hot each afternoon, but the mornings may be refreshing. Maybe. We’ll see!