News Detail

Susan Joslyn’s co-authored paper titled "The Cry Wolf Effect and Weather-Related Decision Making" was cited in this article from The Advocate about storm alert false alarms

'People will only tolerate so many false alarms': Experts talk Tropical Storm Gordon forecast

BY STEVE HARDY | SHARDY@THEADVOCATE.COM

Louisiana officials declared an emergency, called out the National Guard, shuttered schools and closed courthouses as Tropical Storm Gordon drew near, but the weather system bucked east and left the Pelican State unscathed.

Such false alarms are the cost of a robust emergency response system, scientists and government officials said Wednesday. Some worried residents could become desensitized to future alerts.

"People think they're getting over-warned," said meteorologist Frank Revitte of the National Weather Service's Slidell office, which issues forecasts for southeastern Louisiana.

Forecasts were much less refined decades ago. With the assistance of modern technology, the three-day outlook now is as accurate as the 24-hour forecast of 15 or 20 years ago, Revitte said.

That's shrunk the so-called "cone of uncertainty" that shows the possible range a storm system is likely to travel. It's a major improvement over a single line or a spaghetti model, said Kam-Biu Liu, chairman of LSU's Department of Oceanography and Coastal Sciences.

But the cone forecasts issed by the National Hurricane Center still paint with a broad brush. On Sunday evening, forecasters predicted Gordon could make landfall anywhere on the Louisiana or Mississippi coast. Storms could also veer far from the cone, which is designed to predict the path of two-thirds of systems, Revitte said. Gordon made landfall late Tuesday just west of the Mississippi-Alabama state line, just inside the cone's projection.

There are just still a lot of vagaries that dictate how tropical storms move; the National Hurricane Center does a pretty good job predicting where they'll land, said Louisiana state climatologist Barry Keim.

In Gordon's case, the prediction prompted authorities to take steps like mobilizing some National Guardsmen — which has to be planned a few days in advance — even though the system eventually swung east.

"The threat was real" at the time the Louisiana officials had to start disaster-mode activities, said Mike Steele, spokesman for the state's emergency preparedness office.

Decisions like school closures are made locally, but no superintendent wants to answer to families if a single bus full of children slides off the road, and the composition of Louisiana's coast means that hurricanes have greater impact farther inland than elsewhere in the country, Steele said.

"(Hurricane) Katrina was such a game-changer. You just don't take a chance," Steele said.

University of Washington psychology professor Susan Joslyn co-authored a 2015 paper titled "The Cry Wolf Effect and Weather-Related Decision Making" in which she examined how people think about risk analysis and extreme weather. For events like hurricanes, even experts don't know exactly what is going to happen, so they err on the side of caution, she explained in an interview.

"The costs are so great ... in terms of human life that there are more false alarms than misses," Joslyn said. "False alarms are part of it. There are always going to be false alarms."

Read the entire article here .