Meteorologists first had an idea that a storm may be coming for this part of Texas last weekend, after Tropical Storm Barry made landfall in Mexico. “When you have a tropical system, it’s just pumping moisture northward,” says Chris Vagasky, an American Meteorological Society-certified digital meteorologist based in Wisconsin. “It starts setting the stage for heavy rainfall events.”Local officials say they had no warning of what was coming. There’s more than a little special pleading in that.
The NWS office in San Antonio on Monday predicted a potential for “downpours”—as well as heavy rain specifically at nighttime—later on in the week as the result of these conditions. By Thursday, it forecast up to 7 inches of rainfall in isolated areas.
Predicting “how much rain is going to fall out of a thunderstorm, that’s the hardest thing that a meteorologist can do,” Vagasky says. A number of unpredictable factors—including some element of chance—go into determining the amount of rainfall in a specific area, he says.And yeah, let’s all blame NOAA:
“The signal was out there that this is going to be a heavy, significant rainfall event,” says Vagasky. “But pinpointing exactly where that’s going to fall, you can’t do that.”
Flash floods in this part of Texas are nothing new. Eight inches of rainfall in the state “could be on a day that ends in Y,” says Matt Lanza, also a certified digital meteorologist based in Houston. It’s a challenge, he says, to balance forecasts that often show extreme amounts of rainfall with how to adequately prepare the public for these rare but serious storms.
And meteorologists say that the NWS did send out adequate warnings as it got updated information. By Thursday afternoon, it had issued a flood watch for the area, and a flash flood warning was in effect by 1am Friday. The agency had issued a flash flood emergency alert by 4:30am.As an aside, I signed up for Next Door because the county told me emergency announcements would appear there first. I still get reliable emergency alerts on television. I don’t get any from Next Door. And I’ve never been on Facebook, and don’t want to be.
“The Weather Service was on the ball,” Vagasky says. “They were getting the message out.”
But as local outlet KXAN first reported, it appears that the first flood warnings posted from safety officials to the public were sent out on Facebook at 5am, hours after the NWS issued its warning.
“Clearly there was a breakdown between when the warning was issued and how people got it, and I think that’s really what has to be talked about,” Lanza says.
“I really just want people to understand that the forecast office in San Antonio did a fantastic job,” Vagansky says. “They got the warning out, but this was an extreme event. The rainfall rates over this six-hour period were higher than 1,000-year rainfall rates. That equates to there being less than 0.1 percent of a chance of that happening in any given year.”Cold comfort to the families of the dead and the missing. But then, so is blaming NOAA.
And if you want some of the human side of this story: here. It’s being called a 100 year flood. Ironically, Camp Mystic will be 100 years old next April.
Funny how these things work. About 10 years ago we had a tremendous downpour in Santa Fe. No one was seriously injured, but there was a great deal of flooding. I had three hitherto unknown leaks in my ceiling and a rush of water from my neighbor's yard not only knocked a hole in our common fence, but knocked down my own fence on its way to the arroyo. We were assured that it was a "thousand year flood" that shouldn't occur again for the rest of the millennium. Four days later we had another one.
ReplyDeleteI have had some real questions about the current state of the National Weather Service. Like most people I'm always checking the weather app on the I-phone, and though predictions of rain during the summer monsoon have always been a little iffy, this summer the app has been almost worthless. Just a couple weeks ago, for example, we had to do some shopping downtown, and the app showed no rain in the coming days. Sure enough, we got downtown, walked into a store, and suddenly it was thunder, lightning, hail and a huge downpour, and we had to rush home through it, since we'd left all the windows open, and the window fans running.
So I don't know if there's any relationship between the staffing cuts and the decay in accuracy. It may be a coincidence. But I will assume that, with the poor weather people, like so many federal employees, under siege from the administration, things certainly aren't going to get any better.
Incidentally, I saw that Camp Mystic is not far from Mo-Ranch, the Presbyterian camp and retreat, where I spent a number of summers as a kid, mostly in choir camps, with frequent swimming intervals in the Guadalupe.
I wondered how far it was from Mo-Ranch. My memory is the sleeping quarters were well up hill, along with the other facilities, from the river. The Barbed Wire article indicates the youngest campers were housed nearest the river. In the flood plain, IOW.
ReplyDeleteAnd my experience with flash floods is that mostly, you find out the warnings mean you when it’s too late to leave. Or you flee into it. Especially in the Hill Country. ðŋ