Tropical Depression 5 on the way to becoming Edouard and impacting Texas & Louisiana as a feisty little storm

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In brief: We take a big picture look at what will push Tropical Depression 5 likely into Tropical Storm Edouard later tonight, as well as what will impact its intensity going into tomorrow. We talk about the wind potential on the coast and the flooding potential inland.

Over at Space City Weather, Eric takes a look at how TD 5, or what should become Edouard will impact the Houston area. My purpose here is to zoom out a little and take a look at TD 5 from a larger perspective.

First, as of this evening, the storm center of Tropical Depression 5 is located south of Vermilion Bay, Louisiana. Maximum sustained winds are 35 mph, so we’re not yet at tropical storm intensity.

Tropical Depression 5 over the northwest Gulf on Monday evening just after 4 PM CT. (WeatherFront)

There has been hurricane hunter activity in the depression throughout the day, and the read is that the circulation is becoming better defined. They’ll be back out tonight, and given how things have gone today, I would not be the least bit shocked to see this upgraded to a named storm with the 10 PM CT advisory.

The track forecast for TD 5 is actually relatively straightforward and simple. It will continue west northwest to northwest and make landfall somewhere between High Island, TX and Cameron Parish, LA tomorrow afternoon or evening.

Other than a few outliers, the Google Deep Mind 1,000 member ensemble is in strong agreement on a landfall between High Island and Cameron, LA. (tcatlas.org)

TD 5 has about 24 hours over water to do whatever it will do.

So, what will it do? Normally, we’d look at a system like this and say, “Ok, weak to maybe moderate tropical storm, and that’s that.” TD 5 is slightly different. It’s small, it’s healthy “under the hood,” and it’s over very warm water in an extremely low shear environment. The key in that sentence is that it’s small. Small storms deserve love too. And in fact, sometimes these smaller storms can thrive in this part of the world, easier to wind up. And with only 24 hours over water, this storm will probably come ashore while intensifying, meaning it may punch a little above its weight class in terms of coastal impacts.

The latest NHC forecast brings TD 5 to 60 mph at landfall near Sabine Pass, TX. About 20 percent of Google 1,000 member ensemble members bring TD 5 above 60 mph at landfall, with about 5 to 10 percent doing so as a hurricane. Google’s operational WN2 model is not as excited with this, but I think this is an excellent use case for a 1,000 member ensemble. It gives you a more adequate dispersion of members in terms of intensity, and with small storms that can easily fluctuate like this one should, that’s helpful.

Let’s talk about the potential of a higher-end outcome. Let’s say TD 5 becomes a hurricane. Heck, even just a strong tropical storm. What sort of wind would we be looking at here? The answer is “a very compact, localized” wind field that would quickly drop off as it moved inland.

The wind field of stronger wind gusts from TD 5/Edouard should only be about 30 miles or so wide, and it will likely drop off significantly once inland. (WeatherFront)

In this scenario, you’d have strong tropical storm or hurricane-force gusts on the immediate coast between High Island, TX and about Johnson Bayou, LA. And the western flank of that may even be a little generous. By the time you got to Winnie, Nederland, Beaumont, Orange, Vinton, or Sulphur along I-10, you’d be talking about low-end tropical storm force wind gusts. At best. The storm would weaken rather fast once onshore, and this would likely substantially crush the wind intensity. In fact, if you run the HWRF, shown here, out 3 hours from here, you get max wind gusts in the 40s south of I-10 and 30s north of I-10.

Also, notable since the broader media will tie this into “Greater Houston,” this outcome would keep tropical storm force winds away from the entirety of the Houston Metro area, except maybe, maybe Galveston and Bolivar.

So, if you live on the coast or just inland between High Island and Johnson Bayou, I encourage you to prepare as if a strong tropical storm or Category 1 hurricane were coming.

In terms of rain, the good news is that the system looks generally progressive. The remnant center of it should be somewhere south of Dallas or east of Temple by Wednesday afternoon. But, the system is rather moisture-laden, so it will be able to dump some hefty rain near where the center tracks. In general, I would expect about 1 to 3 inches of rain east of I-45 with a band of 3 to 7 inch totals along the center track. That’s what should track through western Jefferson, eastern Chambers, Liberty, Hardin, Tyler, Polk, and San Jacinto Counties. Within that 3 to 7 inch corridor, there could be a bullseye closer to 10 inches in one or two spots.

The heaviest rain from TD 5 will likely fall east of the Houston Metro and west of Beaumont. (Pivotal Weather)

In the Houston Metro, we cover that at Space City Weather, but there is likely to be a very sharp gradient where parts of the area see nothing at all, up to an inch, then a quick escalation to 3, 4, 5 inches or more somewhere east of I-45. For Beaumont-Port Arthur, this looks like the heaviest rain will fall south and west of those cities, but it’s possible we see over 3 inches in spots. An inch or so is possible in Lake Charles, as well as around the periphery of where TD 5/Edouard “dies” in Texas, be it near Waco or Lufkin.

While this is probably not a severe flooding risk, there will be pockets of flash flooding possible later tomorrow through Wednesday morning, so just be advised of that in those areas.

We’ll update the situation again in the morning. Stay safe!

Invest 97L, yet to organize, looks to dump some heavy rain east of Houston and west of Beaumont this week

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In brief: Invest 97L has an imposing satellite image but it has yet to make serious strides toward actually organizing yet. It remains distinctly a heavy rain and flash flooding concern, particularly east of Houston heading into midweek. But folks close to the coast east of Houston should continue to monitor Invest 97L for potential development before it comes ashore tomorrow.

Invest 97L

The good news is that scary looking satellite imagery is not correlated to tropical system intensity. On satellite, Invest 97L looks quite imposing this morning, but it’s notable that almost all the storminess is to the east of the presumed center.

Invest 97L has an imposing look on satellite this morning (WeatherFront)

Aside from that, we remain around 70 percent odds of potential development as of the overnight update from NHC. In terms of things that have and have not changed otherwise overnight: The track is mostly unchanged, generally toward the Upper Texas Coast with the center arriving onshore sometime tomorrow afternoon or evening. If there is a slight change in track, it’s that more tropical models are a little farther south and west with 97L, perhaps owing to the fact that it has not developed yet.

Tropical modeling brings the center a little closer to Bolivar than High Island or Port Arthur, partially due to the fact that it has not organized yet. (Tropical Tidbits)

Weaker systems will tend to go a little farther west before turning northward, and that could be what’s at play here. Either way, it’s good news that it has not organized yet. The more time it takes organizing also reduces the amount of time it has to intensify. So in general, we’re still looking at a decent chance at a tropical depression and a moderate chance at a tropical storm by landfall. People on the Texas coast, especially east of Houston should continue to monitor Invest 97L through the day.

What we are likely to see is more rain, however. Rain totals continue to slowly increase in East Texas. We would now expect about 1 to 3 inches, with isolated pockets of 3-5 inches of rain or more east of Houston and west of Beaumont. It’s not out of the question that someone sees close to 10 inches of rain from this before all is said and done, so obviously areas of flash flooding will be a concern, perhaps not in Houston proper, but east of there.

Total rainfall from 97L will likely exceed 5 inches in spots east of Houston and west of Beaumont. (WeatherFront)

So, bottom line? A tropical storm remains a distinct possibility out of Invest 97L. A depression is a good bet. The main threat will be heavy rain and flooding between Houston and Beaumont and inland from there. But folks east of Houston, between Bolivar and Port Arthur will want to keep an eye on 97L over the next 36 hours before landfall, in case it does try to organize faster.

More later today.

Invest 97L inching closer to something more formal Sunday evening

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In brief: Invest 97L continues to hold its own in the Gulf, with some further increasing potential that it may develop into a depression or named storm before coming ashore in Texas or Louisiana on Tuesday. The heavy rainfall threat, especially north of Houston and east of I-35 seems to also be increasing some.

This post will be fairly brief, but I wanted to add some thoughts regarding Invest 97L before the morning. First off, it looks mostly the same this evening as it did earlier today, which is a bit of a small feat in and of itself, as typically these nascent systems strengthen more overnight and weaken during the day. That it has held its own indicates it’s probably in shape to organize a bit further.

Invest 97L is holding its own this evening south of Louisiana. (WeatherFront)

What has changed as a result of this and recent model guidance is two-fold. First, a bigger risk of locally heavy rain in Texas and Louisiana. Second, a higher chance that 97L will actually develop into a depression or storm. The NHC has raised odds to 70% this evening, but I would think the odds are closer to 90% for a depression and 60 to 70 percent for a named storm. Either way, they are now higher.

Modeling is in good agreement on both track and timing of the system, giving it about 36 or so more hours over water before making landfall near Port Arthur or High Island, TX sometime during the second half of the day Tuesday. Models have become a bit more scattered in terms of intensity of 97L today, with a few more pulsing up into tropical storm status.

Invest 97L has limited time over water, but it may try to make the most of what it does have to become a depression or named storm. (Polarwx.com)

At this point, if you live on the Upper Texas Coast east of Baytown through about Cameron Parish, LA, it makes sense to prepare for a tropical storm. This means the potential for heavy rain, gusty winds, some minor to moderate coastal flooding, and rough seas. The problem with these smaller systems like 97L is that they don’t give you a whole lot of warning and then all of a sudden they ramp up. Think of Hurricane Humberto in 2007 as a prime example of this. It wound up from a disturbance to a small hurricane in about 24 hours. The initial forecast from the NHC for Humberto had max winds of 45 mph. I’m not saying Invest 97L will do that; our modeling has improved quite a lot in 20 years. But I am saying that model guidance still doesn’t always capture these smaller storms properly, and it’s better to err on the side of caution in these areas, especially to the east side of where the storm may come ashore.

Updated NBM forecast rainfall over the next several days. (WeatherFront)

I am growing a little more interested and potentially concerned about the potential for flash flooding in parts of Texas from 97L, especially north of Houston and east of I-35. Rain totals have trended up a good bit since earlier today, and I think the potential exists for rain totals to increase more over the next couple days. I’d watch the triangle between Beaumont, College Station, and Lufkin closest right now, but let’s see how things play out over the next couple days.

More in the AM.

Dolly’s remnants, Invest 97L provide low end development potential and some rain chances

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In brief: Invest 97L may end up being a beneficial rainmaker for parts of Louisiana and Texas over the next couple days, as it tries to develop before moving ashore on Tuesday near the Texas/Louisiana border. Meanwhile, Dolly’s chance at a second act seems minimal at this point, but it’s worth watching the pattern in the eastern Gulf in a little over a week.

Invest 97L to bring some rain to Texas and Louisiana

We’ll start closer to home today, with an area of possible development that felt like it sort of crept up out of nowhere after Friday morning. We have a disturbance now, Invest 97L, with about a 50 percent chance to develop over the next couple days.

Invest 97L swirls close to the southeast Louisiana coast on Sunday afternoon. (WeatherFront)

Overall, the system has a pretty good deal of thunderstorm activity with it, not terribly dissimilar to what we saw with Bertha a few weeks ago. Whatever the case, there have been worse looking systems this summer. The models are not especially bullish on further development of 97L. Google’s Deep Mind 1,000 member ensemble has about an 8 percent chance of development, while the operational model doesn’t develop it all. And indeed, while wind shear isn’t terribly hostile where it currently sits, it should pick up a little bit over the next day or so. Not a lot, but perhaps enough to stave off a depression? We’ll see.

Google’s 1,000 member ensemble is lukewarm on development, but it does track it toward the upper Texas coast over the next 2 to 3 days. (tcatlas.org)

Either way, expect 97L to track generally west to northwest over the next couple days, bringing it ashore somewhere near Port Arthur or Sabine Pass by Tuesday. At this point, I would not expect much more than an open wave or a depression. And in fact, any rain from 97L would be most likely welcome in a region that has seen drought begin to really accelerate in the last month or so. But, if 97L can wrap itself up a little faster, over quite warm waters, sure we could end up with a tropical storm. The next name on the list is Edouard.

Once inland, 97L will probably get somewhat boxed in by high pressure to the east that’s going to try and build over top of it back to the west. I don’t think this will “trap” 97L over Texas, but it may act to slow it down a good bit. While this likely won’t lead to a major flooding issue, we could see some daily thunderstorms with heavy downpours possible. Modeling won’t do well capturing that right now, but I would not be shocked to see the rainfall totals shown below begin to inch upward a little over the next couple days between Dallas and Houston.

Forecast NBM blended precipitation forecast through Saturday morning. Totals may need to come up some in Texas. (WeatherFront)

Bottom line with 97L: Worth keeping an eye on for Gulf Coast residents, especially near Beaumont, Port Arthur, and Cameron Parish, LA. Keep an eye on the rainfall forecast farther inland across Texas in case things should change.

Dolly second act chances?

Let’s check on Dolly’s remnants this afternoon.

The leftovers of Tropical Storm Dolly are still producing storms, but they’re not exactly organized. (WeatherFront)

The good news is that rains are falling in the drought-stricken Caribbean. So that’s coming to pass. From here, Dolly’s road is bumpy but not necessarily enough to destroy it. By Thursday, whatever is left of Dolly should be near Cuba and the Bahamas. I would assume it does not look a whole lot different at that time.

From there we embark on a bit of a choose your own adventure with this one. Some models draw it into the Gulf with some further development before crossing Florida and hooking back out to sea. Others keep it subdued without much development. Right now, the camps seem split with the AI modeling very subdued on any future organization and the European model a little more aggressive. There are some other models trying to put something else in the eastern Gulf around the time that Dolly gets there it seems as well. Most modeling takes that across the Florida Peninsula and out to sea.

The more aggressive European ensemble forecast over the next 9 days. (Weathernerds.org)

So, this is just kind of sloppy right now, and there’s not much signal to draw out of this noise. What’s it mean? It means we should probably continue to keep track of both Dolly’s remnants and the potential for development in the eastern Gulf in about 8 to 10 days from now. But at this point, there’s no real reason to worry or get worked up.

Beyond that, the tropics are mostly subdued for the time being. But as is the case heading into the peak two to three weeks of the season now, you do want to keep track of each system, even the little ones.