Mid-morning Sunday Houston area weather update

As of this morning, not much has practically changed, with widespread flooding continuing and heavy rainfall continuing. Please see our previous post for a re-hash of safety information I think everyone has heard to this point.

Now & Today

As of mid-morning, we continue to see waves of rainfall push through the area.

Rain continues this morning. (GR Level 3)

 

Over the course of the afternoon, expect the pace of the rain to perhaps slow down a bit. This isn’t being optimistic…this is actually rooted in some of the weather models. We’ll continue to see widespread flooding problems, but any opportunity to slow added rainfall will help slowly drain a little bit of the water out of the region. Every little bit helps.

The heaviest rainfall today will occur north and east of the city it looks like. We’ll continue with isolated tornadoes.

Tonight & Monday

The nighttimes are when we are most vulnerable. Unfortunately tonight doesn’t look ideal. I don’t necessarily expect a repeat of last night, but even if half of what fell last night occurs tonight, there will be a recurrence and worsening of flooding in spots (perhaps not everywhere, but definitely in parts of the Houston region). Weather models indicate another substantial amount of rain is possible through tomorrow afternoon. Bottom line: You have to plan for another difficult night tonight and day Monday.

Beyond Monday

Harvey’s forecast track remains difficult to perfectly pin down, but a general drift south and east through Tuesday before it finally starts lifting north Wednesday and Thursday.

Forecast track of Harvey shows something of an end in sight. We just have to be patient. (NHC)

 

There may have been rumors circulating about Harvey pushing back out over the Gulf and reforming into a storm or, especially a hurricane. While the storm’s center may reemerge into the Gulf, we feel that significant strengthening is unlikely. For now, there is little need to worry yourself further about storm surge or very strong winds in an already awful situation.

As Harvey lifts north later Wednesday and Thursday, the rain won’t shut off, but it will become more sporadic and manageable. No, it doesn’t help, but we should hopefully begin the long road of recovering. Another update later this afternoon. Be safe.

Posted at 9:55 AM Sunday by Matt

 

Catastrophic flooding event will continue in Houston

Good morning. Heartbroken and sick over some of the news and stories this morning. Thoughts and prayers go out to everyone affected. Unfortunately we need to talk about the weather, as this will continue.

Off the top, we can’t tell you much more than to follow instructions of local government, NWS Houston, and Harris County Flood Control. Stay tuned to a media outlet using radio/TV.

A Civil Emergency Message has been posted regarding folks trapped in their homes.

Via NWS Houston and Jeff Lindner: Residents trying to escape rising floodwaters should go on their roof, do NOT go into the attic. Also if calling 911, stay on the phone until it is answered.

I am directly copying Eric’s words from overnight here:

“Speaking of that, for the first time ever, the National Weather Service just issued what it is calling a “Flash Flood Emergency for Catastrophic Life Threatening Flooding.” And not to sound too flippant, but that sounds really bad. You should probably heed their advice—WHICH IS SIMPLY DO NOT TRAVEL. DO NOT IMPEDE WATER RESCUES IN PROGRESS.

Is that clear enough?

(National Weather Service)

If you home has flooded, then we are truly sorry. No words from us can begin to address that problem. But we can say that millions of people have been through this before, and it can be done. Some good, basic advice, can be found here. And although this handbook from FEMA is dated, it provides detailed steps to take care of yourself, your family, and your property in the aftermath of a flooding event.”

Weather going forward

As of 6:30 AM rains continue to fall heavily, at a rate of 1-3″ per hour in spots.

No words. It continues. (College of DuPage)

 

Over the next 12-18 hours, expect this cycle to continue. Waves of rain, heavy at times. There will probably be breaks. What this does is both limit how bayous can drain and worsens flooding in spots. It’s bad and it’s going to likely stay bad through the day. Some folks may see another 6-12″ of rain today and tonight.

Rain will continue in similar fashion on Monday as Harvey drifts south and then begins to make the turn back north. The setup begins to change a bit on Tuesday, but at this point I still think periods of heavy rain are likely. Harvey should finally move far enough north on Wednesday to not shut off the rain, but reduce it to manageable levels.

In addition to the rain, Tornado Warnings continue cropping up from time to time. This threat will continue through the day today, with hopes that it will be at a slower pace than the last two days.

We’ll have another update around 9 AM or so. Please be safe.

Posted at 6:40 AM Sunday by Matt

So we’re now under a “Flash Flood Emergency for Catastrophic Life Threatening Flooding”

Well, it’s sure been a night in Houston. And as mad as it’s been, it seems we are just not done. I feel almost guilty for writing about this, as I so desperately wish to report some good news for a change. Because it sure feels like we ought to be done with the rain. At least for a little while.

To put this into perspective, let’s review. First, around sunset, Band 1 stormed through Houston from west to east, topping off our bayous. Then it stalled over east Houston. Next came Band 2, which as it moved in from the west intensified about the time it reached the western city limits. Then, having made some unholy alliance with Band 1, the two merged more or less over downtown Houston. This created what meteorologists properly call a seething nexus of hate (and rain).

But no, we’re not done. Whereas it was once a thin line of showers, Band 3 is fattening up as it moves up the Highway 59 corridor toward Houston. Here’s the state of play as of 1:45am CT on Sunday.

Houston’s crazy night on the radar continues. (Space City Weather/Intellicast)

I can’t really say whether Band 3 will strengthen further as it rotates east-northeast, but it seems already plenty healthy to bring another 3 to 5 inches of rain as it crosses Houston. And that assumes it keeps moving, rather than merging with the previous to rain bands to form a trinity of calamity. If that happens, God help us all.

Speaking of that, for the first time ever, the National Weather Service just issued what it is calling a “Flash Flood Emergency for Catastrophic Life Threatening Flooding.” And not to sound too flippant, but that sounds really bad. You should probably heed their advice—WHICH IS SIMPLY DO NOT TRAVEL. DO NOT IMPEDE WATER RESCUES IN PROGRESS.

Is that clear enough?

(National Weather Service)

My wife, bless her, just asked me if Band 3 was it for the night. I wanted nothing more than to fall in her arms and tell her yes, this was it. By God, yes. Let’s go to bed and forget this ever happened. It had to be it, surely.

Well, by looking at the radar I’m sort of hopeful this is it. But some of the very same high-resolution models that indicated earlier Saturday that Houston was going to get slobberknocked tonight suggest that Band 3 isn’t it—that our rains will continue well into Sunday morning.

I dearly, dearly, dearly hope those models are wrong. Houston’s future (and our collective sanity) more or less depend upon that now.

End note: If you home has flooded, then we are truly sorry. No words from us can begin to address that problem. But we can say that millions of people have been through this before, and it can be done. Some good, basic advice, can be found here. And although this handbook from FEMA is dated, it provides detailed steps to take care of yourself, your family, and your property in the aftermath of a flooding event.

Posted by Eric at 2am CT on Sunday

A bad situation in Houston has turned worse. Much worse.

A bad situation has turned worse. Earlier tonight we discussed two major concerns for the rest of the night—that a primary rain band moving north-northeast across Houston would stall, and that a second rain band moving toward west Houston would strengthen. Both subsequently happened, creating a super-mega-rainball of doom that that stretched across Houston from Tomball and The Woodlands down to Texas City. And as of 12:45am CT on Sunday, it shows no signs of abating.

Among the extreme rainfall data we have already seen tonight is that 9.92 inches of rain fell within three hours over portions of Southeast Harris County, and 6.60 inches fell within a single hour along Clear Creek in Friendswood. According to the Harris County Flood Control District, both of these totals are 500-year flood events.

Rain totals for Saturday in Harris County. (HCOEM)

Another data point that is concerning in the extreme: The Houston-Galveston office of National Weather Service has issued three Flash Flood Emergencies tonight for the Houston region. It had only ever issued one before in the five years or so that the forecast product has existed.

At some point, this must end. But it does not appear likely to do so anytime soon. It is not clear to me whether the homes flooded by Harvey in the greater Houston area will tally in the thousands, tens of thousands, or hundreds of thousands, but it will be many. This community will have to come together after another devastating flood that seems likely to approach the same magnitude as that of our previous reference event, Tropical Storm Allison. That is two historic floods in less than two decades. Hopefully, we will learn from this. Certainly, we will rebuild.

Our general thinking at Space City Weather has been that tonight, and Sunday morning, would be the worst of the flooding Harvey will throw at us. We had hoped to get through the next 12 to 24 hours with minor wounds, but that will not be the case. Now, future rainfall from Harvey over subsequent days, although unlikely to approach the magnitude of tonight’s terror, will only worsen an already deep wound.

Key messages

  • This is an extremely dangerous flooding situation for the Houston metro area
  • Stay in your location
  • The heavy rains from Harvey are likely to continue into Sunday morning, worsening an already borderline catastrophic situation

Posted by Eric at 12:45am CT on Sunday