In brief: Invest 98L, the Gulf tropical disturbance, will bring an enhanced chance of showers or storms to Houston today and Saturday, but nothing much more than that. After that exits, we maintain typical August weather with heat, humidity, and daily shower and storm chances.

Today/Invest 98L

First off, let’s get the elephant in the room taken care of: Invest 98L, the tropical disturbance approaching the South Texas coast is becoming less likely to develop now, particularly because it’s quickly running out of runway to work with. Odds remain 50% per the NHC, though if it does develop, it would be a tropical depression for about 3 to 6 hours or less before reaching land in South Texas.

That being said, it looks somewhat interesting on satellite this morning, conversationally at least.

This may look a little scary, but in reality, there is no low-level circulation so while there are some heavy thunderstorms and heavy rain underneath this blob of clouds, the system is not organizing much. So you can disregard any meaningful tropical development (wind, coastal flooding) elements of this for the most part.

What we will watch for at least is rain.

We don’t expect a ton of storms here today. But as this blob of storms lifts toward the coast, watch for development coinciding with daytime heating from Matagorda Bay up through Galveston, quickly moving inland. The one thing that will probably limit flooding is that storm motion today looks pretty quick. Unless we end up seeing several storms in a row over the same area, expect a few places to see perhaps an inch or two in less than an hour, some quick, minor street flooding, and then hopefully calmer weather. It’s possible that we also see a localized stronger storm with gusty winds as well.

Overall, the impacts of the tropical disturbance should be for a slightly more active August afternoon today. Even on slightly active days, some neighborhoods may not see any rain at all, so that’s possible too.

It’s extremely humid outside this morning as some of that added moisture works into the area. We had some of our warmest overnight lows of summer in some parts of the region yesterday, and we’ll be close to matching or exceeding them today (Jamaica Beach has not fallen below 86 degrees as of this writing for example).

Saturday

With the tropical disturbance dissolving inland, we’ll be left with added moisture and onshore flow Saturday. For now, I’d say this is pretty typical August weather, but I wouldn’t be entirely shocked to see a few repetitive thunderstorms that cause some minor street flooding tomorrow. Otherwise, just look for high humidity and warm to hot temperatures in the 90s.

Sunday & Monday

We should see relatively calm weather here, with just a continued slight chance of afternoon thunderstorms. Coverage should be a little less than it will be today and Saturday however. Highs in the mid-90s.

Rest of next week

High pressure is going to flex and expand in the Rockies and central Plains. This should open the door to some rain and thunderstorm chances out of Louisiana into southeast Texas, combining with sea breezes in the area to keep us somewhat active. Look for mid-90s continuing.

In brief: The National Hurricane Center has raised the odds of a tropical depression or storm forming in the Southern Gulf during the next day or two. This post seeks to quell any fears this may cause Texas residents. In the greater Houston area we can expect elevated rain chances on Friday and Saturday, but nothing extreme.

Invest 98L status

Early this afternoon the National Hurricane Center increased the likelihood that a tropical system in the extreme southern Gulf, Invest 98L, will form into a tropical depression or storm during the next two days. The odds this morning were 20 percent, and as of 1 pm CT they are now 40 percent. Accordingly the color of the “tropical blob” on the hurricane center’s site has gone from yellow to orange. This has prompted a number of questions from readers about this system, and a measure of concern.

Our most important message is that residents of the greater Houston metro area really should not be concerned.

We will get a better idea about the nature of this system later today when a Hurricane Hunter aircraft flies into it to retrieve data about wind speeds, air pressure, and more. In any case, as of early afternoon on Thursday, the system does not have a closed circulation. However the satellite appearance is improving (in the sense that it is becoming better organized) and there are increasing amounts of thunderstorms. So it is moving in the right direction toward becoming a depression.

It is therefore plausible that this could become a tropical depression or a low-end tropical storm during the next 24 hours. However, by Friday afternoon or evening this should have moved inland, likely somewhere between Brownsville and Corpus Christi. Given this short window of opportunity, we think there is a pretty hard limit on how strong the storm can get.

The primary impacts from Invest 98L will therefore be rainfall. And although we can never be too sure about tropical systems, in August, moving into Texas, this one appears to be largely beneficial in terms of the precipitation it will produce. For the greater Houston region this means an elevated chance of showers, some of it potentially heavy, on Friday into Saturday. Coastal regions face the highest risk, with some areas perhaps seeing a bullseye of 1 to 3 inches of rain. Still, I expect most people will receive less than 1 inch, with the majority of that probably less than 0.5 inch.

More tomorrow.

In brief: Summer is by no means over, but based on climatological temperatures we have now crested the peak heating for this year. And there’s no sign of extreme heat any time soon, with highs in the 90s for the foreseeable future and daily rain chances. As Cypress and Klein saw Wednesday, isolated thunderstorms are a possibility as well.

Past the peak

Don’t look now, but fall is on the horizon. We are still about one month away from having any real expectation of a decent cold front, but Houston has passed over the ‘hump’ of summer. The traditionally hottest time of year comes from late July through the first 12 days of August. This is when the average high is 96 degrees. As of today, the average high is 95 degrees. So we are taking baby steps.

I don’t want anyone to be fooled, of course. These are climatological averages, and individual years can bring significant variability. Often times the city of Houston sees some of its hottest daytime temperatures of the year in late August and early September. However, the average temperature is lower due to shortening days and the occasional weak front. All of this is to say that we are getting through summer, y’all. And the good news is that, for now, we don’t have any 100-degree weather in the forecast.

Thursday

What we have in the forecast for today is a decent chance of showers, especially closer to the coast. By now you’re familiar with this pattern. Somewhere in the region this afternoon, or early evening, we’re likely to see a decent cluster of showers and thunderstorms. Most of the area won’t see any rain, or just some light sprinkles. But a few places—yesterday it was Cypress and Klein—might pick up 1 to 2 inches. This is likely to be the setup later today as well, and it’s precisely what I mean when I say we will have scattered showers and isolated downpours.

High temperatures will depend on the extent of shower coverage later this afternoon, but most of us should see highs in the low- to mid-90s, with plenty of humidity of course. Nights have been really warm of late, and I expect most of the city will not drop below 80 degrees tonight. Winds remain light, outside of thunderstorms in which there can be strong gusts.

Friday and Saturday

You may have noticed a ‘tropical blob’ highlighted in the Gulf by the National Hurricane Center. This remains unlikely to develop into a tropical depression or storm, and it has a limited window before moving into Mexico or southern Texas late on Friday. (If there’s a significant change to this outlook, we will update the site immediately. But we don’t expect this to happen).

Regardless of development, this system will inject a little more moisture into our area. This should raise rain chances to 50 or 60 percent on Friday and Saturday in the greater Houston area. Overall accumulations will still be on the order of one-half inch (or less) for most locations. But just know there could be some disruptive showers pulsing through. High temperatures for most of the region will top out in the lower to mid-90s on Friday and Saturday.

Sunday and beyond

By the second half of the weekend some high pressure is going to try and work its way into the area, but I don’t think our daily weather is going to change too much. We are likely to see high temperatures generally in the low- to mid-90s (a few far inland areas may push into the upper 90s) with a smattering of afternoon showers and thunderstorms. It should be fairly typical for mid-August in Houston, and as we’ve discussed before, any time we get ‘boring’ weather during this time of year we’re doing very well.

Atlantic tropics

I’ve already mentioned the Gulf tropical low above: It’s not a major concern for us, or probably anyone. Then there is Tropical Storm Erin, which is on its way to becoming the season’s first hurricane. It is likely to pass north of the Caribbean Sea. It will approach the southeastern United States next week but probably (although not yet certainly) curve before reaching the mainland. Bermuda faces a definite risk next week from Erin. Beyond this there are no imminent threats and the Gulf looks quiet for the next 10 days or so.

In brief: Parts of central Houston saw some fairly strong showers and thunderstorms on Tuesday, with a few isolated areas picking up 1 inch, or more, of rain. That pattern of sporadic afternoon storms should occur through Saturday before high pressure asserts a little more control. We also discuss the chances of a tropical system forming in the southern Gulf late this week.

Wednesday

The overall story remains the same for Houston’s weather in the coming days, with hot weather and just enough instability and moisture to support the possibility of scattered showers and isolated thunderstorms. These storms are most likely during the afternoon and evening hours, at a time when kids are coming home from school, participating in after-school activities, or during the evening commute. Today, however, I expect slightly less coverage than we saw on Tuesday. Overall I would say there is about a 30 percent chance of showers, with isolated storms. Highs today will range from the lower 90s near the coast to the upper 90s inland, with plenty of humidity.

One thing that’s been noticeable this summer, to me, is the lighter winds. This is because we have not seen tight pressure gradients (i.e. very strong pressure systems) to really draw in the onshore winds. Today, for example, winds will come from the west at about 5 mph, with only slightly higher gusts. Winds may be a little more pronounced on Friday and Saturday, but overall they look to remain in the 5 to 10 mph range for quite a while.

Thursday and Friday

The forecast remains similar to end the work week, with highs in the 90s. Thursday and Friday may see slightly better rain chances, with 50 percent coverage of showers, and a few embedded thunderstorms. The most likely period for these showers remains the afternoon.

Saturday and Sunday

Saturday should see a continuation of this pattern, with highs in the mid-90s for most locations and a healthy chance of showers and thunderstorms. As high pressure starts to build some, I think most of Houston may push into the upper 90s on Sunday, with decreased (but non-zero, to be clear) rain chances. All in all this should be one of our hottest weekends of the year, which is to be expected in mid-August.

Next week

Temperatures for most of next week look hot, in the mid- to upper-90s, with lots of sunshine. I think rain chances will take a step back toward the 20 to 30 percent daily range. So yeah, full-on summer for Houston.

The tropics come alive

In the Atlantic Tropical Storm Erin continues to struggle with the intrusion of some drier air, but should soon move into more favorable conditions. A hurricane is likely to form later this week, or this weekend. The majority of modeling still shows the system turning before threatening the United States, but Bermuda is definitely at risk.

Additionally the National Hurricane Center is tracking a low pressure system that should emerge into the Bay of Campeche on Thursday or so. There is a slight chance of some development over the southern Gulf, and you always want to keep an eye on anything in that region in August. However, none of the models are particularly excited about this tropical low, and the atmospheric conditions are not super supportive. So, at this point, the most likely scenario is that the low has minimal to no impact on our weather. We’ll see.