Five years after Sandy, National Weather Service threat communication is still a pile of mush


The author, Bryan Norcross, is senior hurricane specialist at the Weather Channel and author of “My Hurricane Andrew Story.”

Five years ago as Hurricane Sandy approached the Northeast, forecasters knew the storm was going to morph into something like a nor’easter by the time it made landfall.

Because of that transition, their message became: ocean-water rise — a.k.a. the storm surge — would be less damaging than a “real hurricane” would produce. And since Sandy wasn’t a “real hurricane,” no advance evacuations of low-lying areas were ordered. New York City’s mayor at the time, Michael Bloomberg, made those statements in a news conference five years ago, when the storm was just two days away from doing more than $60 billion in damage to the most populated region in the United States.

It was a shockingly misguided analysis, of course, that dramatically understated the magnitude of the threat facing the Northeast coast and New York City itself. How could it have happened? The easy answer is to blame incompetent politicians and inefficient government. But the truth is quite the opposite.

The problem was that the National Weather Service did not provide a clear, simple and compelling message. It’s a problem that lingers five years later.

New York City Emergency Management and the Bloomberg administration were staffed with dedicated professionals and skilled politicians. If these people, with threat analysis capabilities as robust as anywhere in the United States, could not deduce that Sandy presented an epic threat to their city and the Tri-State Region four or five days in advance, the conclusion can only be that the information they were receiving misled them, confused them, or both.

Once the forecast settled on a track into the Mid-Atlantic about four days out, alarm bells were ringing among meteorologists. The National Hurricane Center said it was likely there would be “significant impacts … over portions of the U.S. East Coast” in its forecast discussion five days before Sandy’s Monday-evening landfall.

A meteorologist from the National Weather Service was stationed in the New York City Emergency Management office to give briefings to city officials. Those briefings began Thursday, more than four days before the storm hit.

Then as now, an avalanche of warnings and bulletins and briefing materials was generated by the National Hurricane Center and the National Weather Service. As we saw before Hurricane Irma hit Florida, however, the amount of information can be overwhelming. More data does not mean a clearer message. As soon as a storm is a high-profile threat, the public and decision-makers need an “executive summary.” In 2017 as in 2012, that summary is an important missing component of the forecast communications process.

On Friday, three and a half days before landfall, New York City had to make a decision whether to evacuate dozens of nursing homes near the water. It had issued the order a year earlier when Hurricane Irene was threatening. The Irene evacuation was unnecessary in the end, and it was costly. City officials decided not to make the same “mistake” again.

Sandy has disrupted life up and down the East Coast for more than two days, causing fires, floods and snow and leaving millions without power. Take a look at some of the superstorm’s most memorable moments. (The Washington Post)

A number of factors came together that led to that terrible decision, not the least of which was that Irene made landfall as a tropical storm, which did not trigger a post-storm flood of federal money. Irene’s evacuation bills still hadn’t been paid when Sandy was bearing down. In addition, when evacuation-decision day came that Friday, health officials simply didn’t think the storm was going to be that bad.

Clearly, something was missing. High-level public officials tasked with keeping elderly and infirm people safe did not understand the magnitude of the threat, and the Bloomberg administration was still vastly underplaying the risk to the city over the weekend.

What was missing was a bottom line. The forecast information was a pile of mush — seemingly bad and not so bad at the same time.

The briefings from the local National Weather Service meteorologists beginning on Thursday, four and a half days before the storm, forecast four to eight feet of storm surge. Eight feet of surge would have put water into most of those nursing homes, but four to eight feet was exactly the same amount of surge forecast for Hurricane Irene. (Irene ended up producing just over four feet.) And the line at the bottom of the briefing slide said, “While impacts may be similar in some respects to Irene — no two storms are alike.” Mush.

Sandy’s forecast transition to “post-tropical” before reaching the coast was also a source of confusion. Nobody except meteorologists understood what it meant. The impression was that post-tropical Sandy would be a significant downgrade from hurricane status, despite the Hurricane Center’s rhetoric about the danger. Again, mush.

Infamously, because of its forecast that Sandy would no longer technically be a hurricane by the time it hit land, the National Hurricane Center did not issue hurricane warnings for the Mid-Atlantic and Northeast coast. In the end, this had little if any effect on the general public.

Research done during Sandy’s approach found that most people thought that a hurricane watch or warning had been issued. After all, the TV was warning them nonstop.

For emergency management, however, the lack of a warning contributed to the mush. How could Sandy be terribly dangerous if no hurricane warning was issued? For people who don’t deal with hurricanes every day, it’s a reasonable question.

“We just didn’t have enough clarity to pull the trigger, ” an emergency manager told me, some months after the storm. They had possibly dangerous mush, but still mush.

If New York City officials had understood the bottom line — that the surge from Sandy would probably be considerably higher than Irene’s, simply because of its angle of approach — and acted on it, their messages and safety measures would have been significantly different.

As Sandy closed in, the National Hurricane Center began intense communications with the Bloomberg administration to help it understand the threat. It was a hard sell. Cutting through the mush is like turning a battleship. In the end, city officials got it, and ordered an evacuation, but only because they thought that the forecast had changed indicating a stronger storm was coming. That wasn’t the case, of course, but whatever works.

A couple of good changes have been introduced since Sandy. The Weather Service rapidly modified the hurricane-warning protocols to forestall a repeat of that omission. It also now boils down the threat into key messages at the end of their technical discussion. An excellent addition, although it is well hidden in a bulletin not designed for non-meteorologists.

But the official forecast is still a kit — pages and pages of words and graphics. People with expertise and understanding of the process know how to assemble the parts into a reasonably cohesive message. But misunderstand one part, be confused by a few terms, or otherwise assemble it wrong, and you’ve got forecast mush.

The enduring lesson of Sandy is that we need an assembled forecast that anybody can digest to understand the threat. Not every single issue, but enough that they feel the risk. It should be more than a few sentences, but less than a book. An executive summary. And with more people digesting the information on their mobile phone, a sharp and clear bottom line is more important than ever.

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