First round of storms ending southeast of Houston

A somewhat surprisingly wild evening south and east of Houston tonight. As I’m writing this, strong to severe thunderstorms are clobbering Galveston and Jamaica Beach, heading offshore. Lingering storms continue to the west from Texas City across League City into Pearland and Missouri City.

Radar as of 9:15 PM showed heavy rain along the coast, with lingering storms inland south of I-10. (GR Level 3)

Total rainfall has been impressive near NASA, Shoreacres, and El Lago, with three inches falling in an hour in a few spots.

Total rainfall as of 9:15 PM was on the order of 1-4″ in a small area near Johnson Space Center. (Harris County Flood Control)

That has prompted a flash flood warning until 11:45 in that area. Use caution if you’re traveling in that region, as some residual street flooding could occur through midnight.

The storms also produced some awesome skies in the Houston area.

So what’s next?

Weather modeling is actually in decent agreement that this cluster of storms will move offshore and fester for much of the night, before we see things rekindle onshore toward sunrise. Showers and storms should increase in coverage after 3-5 AM as our disturbance swings into Texas. We’ll probably be at peak for coverage of showers and storms in the morning, before everything shifts toward San Antonio in the afternoon.

The best chances and coverage of storms will likely be south of I-10 tomorrow.

So bottom line for the Fourth of July:

  • Heavy rain in the morning, especially south of I-10.
  • More flash flooding of streets possible in the JSC/Webster/Seabrook area.
  • Storms will be noisy with potentially a good deal of lightning once again.
  • Rain ends from east to west by early afternoon for most of us.
  • Late afternoon and evening plans look dry (except well west of Houston toward Brenham and Columbus, where showers will linger til late day).
  • Folks north of Houston may miss out on a lot of the additional rainfall.
  • Additional rainfall: 0.25″ to 0.75″ or less in Montgomery, Liberty, and Grimes Counties and north.1-3″ in Harris, Chambers, Wharton, and Fort Bend Counties. A general 1-3″ with isolated pockets of 3-5″ possible in Galveston and Brazoria Counties.
  • There’s still a degree of uncertainty to this forecast, as modeling could be wrong. Check back in the morning for an update.

More in the morning.

A sloppy Fourth heralds a mini pattern change for Houston

We’ll dive into the forecast for the Fourth of July in a moment. Houston has been plagued by July and August-like heat often since May. Now that we’re in July, the good news is that, at least for a short time, we will reverse course a bit. It will still be hot, but it will actually feel more like May or June than July.

Today

Off the bat, I think today will be mostly trouble-free. Again, if your plans take you east of Houston toward Louisiana, you’ll likely run into showers and storms a good bit of the way beyond Beaumont. Here in Houston, it will be partly to mostly sunny through early afternoon, though clouds should increase later in the day. High temperatures will surge back to the mid-90s once more. I wouldn’t rule out scattered showers or storms later this afternoon or evening for places primarily east of I-45.

Tonight

Our upper disturbance will approach the area later tonight. Ongoing showers and storms in Louisiana may try to hold together as they move into Texas late. Our weather models are somewhat divided on solutions overnight tonight. Possibilities across the Houston area range from “mostly nothing” to “you’re probably going to be roused from slumber at 5 AM because of thunder.” Weather models generally handle these scenarios with mixed results, so there’s a healthy degree of uncertainty here. The radar isn’t exactly lit up in Louisiana this morning, so perhaps this suggests we will need the sun to come up before we get much activity.

But when I look at the “big picture,” meteorologically, I see a strong disturbance approaching overnight. To me, this argues that showers and storms will become more and more likely as the night goes on.

Both the Euro (left) and GFS (right) models suggest a pretty vigorous upper level disturbance nearing Houston by morning, which argues for increasing rain chances later tonight. (Weather Bell)

I would not at all be shocked to see the “roused from slumber” solution win out for some of us. If storms do keep going overnight, it’s not a lock that the entire area would be impacted by them.

So I’ll go with this bottom line tonight: Scattered showers and storms become increasingly likely as the night goes on, with highest odds east of I-45. Expect low temperatures to bottom out in the mid- to upper-70s where it doesn’t rain, and mid-70s where it does.

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A mixed Independence Day coming for Houston

I hope everyone got through the weekend of Saharan dust without too much trouble. We saw a bit of improvement to air quality on Sunday, and we will see further improvement today and tomorrow. It may be unnoticeable by Tuesday. Then we’ll talk rain.

Today & Tuesday

Other than the lingering dust, today will just be another hot one. Look for highs to top off in the mid-90s in Houston, a bit cooler near the coast and hotter inland. It will be mainly sunny. Tuesday will start off similarly. Expect a few more clouds to roll in during the afternoon however. There may be a shower or storm around east of I-45 later in the day. But for the most part, I think Tuesday during the daytime looks good. Any organized storms on Tuesday will be in Louisiana or near Beaumont/Port Arthur. If you’re traveling I-10 east toward Lafayette or Baton Rouge Tuesday afternoon or evening, leave yourself a little extra time.

Fourth of July

Here’s where things get slightly more complicated. We’ve been discussing this since last week, and we have slightly more confidence in how things should go today. A vigorous upper level disturbance will swing across the Gulf Coast Tuesday and into Texas from east to west Wednesday and deliver showers and thunderstorms. Let’s roll through what we expect.

Timing: The start time in the Houston area will vary, but I expect an increasing chance of thunderstorms or showers from east to west on Tuesday night, sometime around and after Midnight, lingering into early afternoon on Wednesday. I think our odds of improving weather go up after 12-4 PM on Wednesday (again from east to west).

Do I need to cancel my plans? If you have July 4th evening plans, I would keep them, as the timing may work out well for fireworks and evening events. The morning and early afternoon will be dicier, so for some area parades, that could dampen things. If you have morning or early afternoon outdoor plans, you may want to have an indoor backup ready to be safe.

How much rain will fall? I believe we should see, on average, one to two inches of rainfall on Tuesday night and Wednesday. There could be a few places that see up to three or four inches of rain, or even a little more.

Total rainfall for Wednesday looks to be in the 1-2″ range on average. Some places will likely see higher amounts, but it’s still too early to say exactly where those will be located. (WPC/Weather Bell)


Flooding? Major, widespread flooding is unlikely from an event like this. As is often the case in Houston in summer, however, street flooding could be an issue in the morning or afternoon, depending on where the heaviest rains occur. Right now I think the most likely window for heavier rain from this system will be from 6 AM through 2 PM Wednesday. That may shift a bit between now and then, however.

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Dry, dusty weekend for Houston

We had a few more thunderstorms yesterday, with a handful of areas (but a fair amount of population) seeing some rain. We may repeat that today before drier weather returns for the weekend. As for the Fourth, well, it’s going to be a close call.

Today

Look for a very similar day Friday to what we saw on Thursday. We’ll see a handful of showers or rumbles of thunder once more. There’s a very small chance that areas northeast of Houston could see a bit more activity today. Otherwise, sun, clouds, and hot. We’ll make another run for the low- to mid-90s. Haze may become a bit more obvious today as the leading edge of the Saharan dust plume arrives in Texas

Saharan dust approaching Texas, as seen on GOES-16 satellite imagery late on Thursday afternoon. (NOAA RAMMB)

Weekend & Monday

There should not be much weather to speak of this weekend. It will be dry and hot. Look for high temperatures in the mid-90s on average. Monday may end up being the hottest of the three days, and I wouldn’t be surprised to see Houston register a 96 and 97 by then. Rain chances are almost never zero in Southeast Texas in summer, but this weekend will be close. We don’t expect much in the way of afternoon showers, even on the sea breeze right now.

We’ll continue to deal with dusty skies, which could again degrade air quality in Houston, so take it easy if you’ll be outdoors. I know this is Texas and most of us are used to the heat, but, coupled with the haze and dust, this weekend will probably feel just a tinge worse than usual. Drink plenty of water, take it slow, and check up on anyone you know that may be vulnerable in the heat.

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