OPINION: After the storm, everybody’s a meteorologist

Jul. 21--A week after Hurricane Barry washed ashore, people everywhere have become expert weather forecasters.

I realized this last Sunday after an irate caller told WWL Radio listeners the fake news media, meteorologists and public officials had conspired to deliver a doomsday forecast just to scare coastal residents. She railed that the 10-20 inches of rain experts had predicted never materialized and that Mississippi River levees never overtopped or broke. The off-the-mark prognostications, she argued, would prompt residents to disregard officials' warnings the next time a storm threatens.

"Wow," I thought, "would this person be happier if the storm had killed someone? Or flooded thousands of homes?"

Predictably, I ran across similar attitudes in discussions and social-media exchanges last week. The know-it-alls have thrived before, during and after every storm I can remember. One of the easiest ways to identify them is to listen for cliches like, "Oh, it's just a tropical storm" or "Nothing to worry about; it's never flooded here before." The know-it-alls don't buy flood insurance because they believe, wrongly, that they don't need it. They know more than any meteorologist about where a storm is going and how dangerous it will be when it gets there.

The know-it-alls are especially good at predicting what a storm will do after a storm has already done it. They knew all along that Barry would drop only 3 or 4 inches of rain on Houma-Thibodaux. They knew all along the hurricane would hit Intracoastal City, 85 miles west, instead of Morgan City, 40 miles closer. The know-it-alls picked the correct computer model early on from more than a dozen spaghetti plots they found on some website.

What hokum.

A few observations:

WHAT THE MODELS SHOWED

News reports and meteorologists have dissected some of the reasons rain never reached crisis level locally and across much of the Louisiana. A story by the news website Vox offers a rundown:

--The storm's unusual shape, lacking a clearly defined eye, and massive size, covering almost the entire Gulf, made it difficult for computer models and forecasters to track where the moisture-carrying clouds would go.

--Barry's slow movement over warm water indicated major rain was likely.

--The storm intensified to a hurricane just before landfall, showing signs it would attract more moisture toward its eye and carry that rain over land.

WHAT REALLY HAPPENED

--Wind shear and dry air over much of the U.S. reduced the storm's intensity and cut rain amounts as Barry made landfall.

--"Most of the moisture, where the 20-plus inches of rain occurred, stayed out in the Gulf of Mexico for longer than expected," meteorologist Dave Hennen told CNN. "By the time it did move inland, the storm had weakened, so the rainfall totals were held down."

--Some areas in southwest Louisiana did receive one to two feet of rain, with Ragley, a small community about 20 miles north of Lake Charles, getting the most. But those areas were far more isolated than the vast portion of coastal Louisiana forecasts had indicated would see such inundation.

Every credible weather expert I've ever heard has cautioned that predicting hurricanes, despite great technological advances, is an inexact science, an educated guess that involves lots of judgment calls about forces of nature that can change quickly. Based on a range of probabilities, they predict a most-likely outcome, not a precise, infallible impact.

However imperfect, forecasts from the National Hurricane Center and other credible sources are better than ever, and each storm provides more data to make them more reliable. In the meantime, I'll consider it a blessing when a storm fails to deliver on a forecast of 20 inches of rain in my neighborhood.

-- Executive Editor Keith Magill can be reached at 857-2201 or [email protected].

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